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+{"metadata":{"id":"02d26a30dddb5b237464c5ca4eb5fcdc","source":"gardian_index","url":"https://cgspace.cgiar.org/rest/bitstreams/130e0389-b664-4f95-a6f6-f688b7b7d6e4/retrieve"},"pageCount":148,"title":"Director General's Report* r2~~ f), ~~","keywords":["It'rrd rOlll rol","n","\"PJ","'90-6IJ-<l5 kglha"],"chapters":[{"head":"","index":1,"paragraphs":[{"index":1,"size":72,"text":"'scarch in thrrc ecologica l zo nes of Nigeria -humid fOl'est, tra nsiti o na l, a nd san-mna -and these zones a rc rcpreseilla li n \" OrcJima lc and soil conditions in ma ny areas of A li-iea . In adcliLio n, researc h is condu c ted in ma n y a reas of Africa in cooperatio n w ith reg-iolla l a nd natio na l progra ms."},{"index":2,"size":239,"text":"Funding lo r I [TA ca me initia ll y li'om the Fo rd and Rockdcller roundations, a nd th e land fo r the experimenta l farm was a llolled by the Government of the Federa l R epublic of Nigeria . Th e [nstitut e is govern ed b,' a Board o r Trustees comprised or 14 members, in cludin g emill en t scientists and representat ives from th e host cOllTury, Africa n tropical areas, a nd ot her regions o r til(' wo rld . (The na mes a nd a fTili a uons of Board members a re listed on page 134. ) Mandate and Objectives: The \" geographi c ma ndate\" o r I [TA includ es the humid and slIbhumid tropical regions of the wo rld , but the Institutc concentra tes its research and tra ining ac ri viti es primaril y on til(\" needs or sub-Sahanlll African countries . The centra l o bj ecti ve, in cooperation with natio na l progra ms, is to uncierla ke resea rch \"\"'hich will make it possible to increase food production , employment , and income in thos(' cou ntri es. A food crisis in man y of th em has been building up over the yea rs as rapid popula tio n growth, droug ht, a nd lagging agricultura l production have brouglll a bout a chronic food defi cit."},{"index":3,"size":263,"text":"Fo ur out of fi ve of the research progra ms of IITA are crop centered: Grain Ll'gumc Improvement , rvlaize Research, Rice Research, and Root a nd Tuber Improvement. The fifth is the Farming Sys tems Program . Specifica lly, the obj ecti ves of these a nd o ther segmcnts of the Institutc a rc to : • Develop farm ing systems, including soil a ncl crop ma nagement practices, tha l wiiJ provide viab le, stab le, and sustainable a lt erna ti ves to traditiona l systems of shifting culti va tion in Africa; lhe major emphasis centers on increasing the producti vit y offi•agile tropi ca l soils while still maint a ining efTective conserva tion in eco logica ll y ba la nced environments. • Fulfill a worldwide responsibility to d evelop a nd implement resea rch progra ms which will lead to improved varieties of cowpeas, yams, a nd sweet potatoes. • Conduct specific research in Ali-ica in cooperation with o ther interna ti ona l cellters a nd na tiona l institutes, to d evelop a nd improve cassava, ma ize, rice, soybeans, plantain , and cocoya ms; here the practical cmphasis is on the distribution of improved plan t ma teria ls to na tiona l research progra ms to assist lhem with thdr pla nt breed ing work and the adapta tion of improv('d varieties to fit loca l conditions. • Transfer new technologies a nd skills, through training, to scientists, technicia ns, a ncl ex tension workers from develo ping co untries."},{"index":4,"size":150,"text":"• Arrange and conduct conferences, symposia, seminars, and workshops to review new research, consider current pro blems, and discuss needs for the future. All the centers work closely with na tiona l agencies. The linkage is vital to keep the work at centers o ri ented to th e needs of th e fa rming communities they arc int cnd ed to serve. In fact, the gains mad e by scientists at the centcrs will ge t transla ted into actual food outpu t only when the national agencies ta ke up th e results, adapt th em to loca l conditions, a nd carry them to th eir farmers. This is wh y g rea t imporla nce is attached to train ing programs. To d a te, the centers have tra in ed mo rc th an 18 ,000 persons, ma inl y fi'om d evelo ping countries."},{"index":5,"size":146,"text":"Each CG IAR-a fHi a ted center is a uto nomous a nd run by an ind ependent Board of The CGIAR, w hich has an executive secretariat provided by the World Bank, meets twice a year to take decisions based on consenstts . Th e m eetings hav(' before them recomm enda tions from a T echnica l Advisory Committee (TAC) comprising a cha irman a nd 12 distinguished scientists drawn eq ua ll y from developed and d eveloping countries. TAC is supported by a secretariat provid ed by the three co-sponsors ofCG l AR a nd located in R o me at FAO headqu arters. Also avai lable to th e semi-annual meetin gs arc reports from ccnters, suppo rting bodies, a nd ad hoc committees th at are set lip fro m time to lime to address specific iss ll es ."},{"index":6,"size":37,"text":"with the concept of accountabi lity to donors, and provid es overall admjnistrativ management support. TAC monitors the scientific performan ce of the centers and centcr bud gcts in the light of defined rcsearch priori tics ."},{"index":7,"size":48,"text":"CGIAR started operations with 15 donor members but by the beginning of 19 number had inc reased to 43 countries, int ernational and regional agencies, and foundation s. Thcy pledged approximately U.S. $ 180 million to support th e resea training programs of the 13 centers in 1985."},{"index":8,"size":98,"text":"Fig ure I . Globallocalio\" of t he 13 CGIAR-supportell i,.'e rna t ional resetu•c/. {lUd train ing cente rs l am privileged to have the opportunity to lead IITA a t this moment in its history. The eyes of the world a rc focused on Africa with its p rofound pro blems of burgeoning popula tion, hunger, a nd ma lnutrition. Althoug h IlTA 's \"geogra phic ma nda te\" within the CGIAR a backlog orbasic knowl ed ge in the plant sciences tha t is no t so readil y a ppli ed to importa nt"},{"index":9,"size":126,"text":"Africa n cro ps (suc h as cassava, ya ms, sweet po ta LOes, a nd va rio us food legumes) w hich a re spread across a wid e diversity o f ecosystems. \\!\\fh a t is encouraging is tha t UTA , in partnership w ith na ti o na l progra ms, is genera ting a stream of techno logies based on resea rc h which is laying the founda tion for wha t I call a \" quiet revo lution\" in the villages a nd on the sma ll fa rms of Afri ca. They may have an even g rea ter elfcc l in the lo ng run th an th e hig hl y publicized \"green revo lutio n. \""},{"index":10,"size":141,"text":"IITA scientists fro l1145 na tions ha ve been tacklin g so me of the mos t difficult problems in interna ti o na l agri culture, and th eir accomplishments arc substa ntial. There is evidence tha t IITA resea rch, d eveloped during the tenure of my pred ecessor, Dr.  IITA 's resources a rc preciolls in rela tion to th e eno rmit y oflh c challenge in Africa. Our fundin g co mes prima ril y from the tax payers of the industria Li zed countries to serve the need s of th e poor in the d eveloping countri es . As UTA a pproaches its 20th year, we have a heavy resp onsibilit y to assu re tha t tiwsc reso urceS a rt' sha rpl y focused o n the mos t urgent tasks."},{"index":11,"size":147,"text":"W e know the p roblems of th e future w ill be different from the problems of tod ay . Fo r exa mple, d emogra phers proj ec t Ali•iea n popula ti on g rowing fro m its present sha re of 10 percent of world po pula tio n to a bou t 25 pe rcent before g lo ba l popUla ti on sta bilizes so meLim ,' in the 2 1st century. This will place ex traordina r y popu la ti on ptTSSUI'l' upo n a ra bk la nd in man y parts of Afri ca . I rTA is one or the f(•w institudo ns with th e scienLifie cxpcrtisc, know ledgc of the local enviro nment, a nd commitment to susta in researc h on th e agri c ultura l problems orthe 2 1st cen tury."}]},{"head":"Strategic Planning Study","index":2,"paragraphs":[{"index":1,"size":115,"text":"As we d eve lop future pla ns fo r I IT A, it is essentia l tha t we es ta blish clearl y d efin ed prio rities a nd stra tegic direc tio ns for the future. This is partic ula rl y import a nt fo r 1 ITA beca use it ha .. \"i a n extrem ely broad forma l progra m \" ma nda te\", a nd it is dea ling with vc ry complex a nd dillicu lt agroecologies. For this reason , II TA Trustees in November 1985 a uthori zed ma n agement to underta ke a Stra tegic Pla nning Stud y in 1986."},{"index":2,"size":85,"text":"The purposes of' th e Stra tegic Pla nning Stud y a rc to hel p provid e a nswers to twu overriding questi o ns: \\\"'ha t a rc Liw possibiliti es of producing scientific a nd technical a d va nces if resources a rc a lloca ted to researc h o n a pa rticula r problem or commodit y? vVha t will he the va lue to socic:t y of the !lew technology if the resea rch e(fort is successful ?"},{"index":3,"size":129,"text":"The Stra tegic Pla nning Stud y will be based on a critica l assessment o f UTA's su bsta ntia l streng ths a nd capaci ti es vis-a-vis o ther in te rn a ti ona l a nd n a tiona l institutions. \"he obj ecti ves a re to sha rpen 1lTA 's instjtutio na l missio n a nd lO provid e a colwfC'r1l f'ra mc\\vork for til(' alloca ti o n of sca rcl' reso urces w ithin a nd across its ra nge of prog ra m ac ti viti {'s. Fin a ll y, th e S tud y shou Id lead 10 a visioll of I ITA 's future a nd goa ls by w hich to mcasure progress ."},{"index":4,"size":195,"text":"Sma ll Stud y G ro ups, consisting of distinguished scientists, ha ve b('ell set up for each progra m to work w ith us in defin ing the iss ues, ca ta lyzing d iscussion , a nd he lping to think throug h prioriti es. The S tud y Groups lo r the commodit y progra ms a rc guideci by the fo llowi ng terms of reft'rl'llce : I ) assess the prest'll t a nd fu t u I'e sig nificanc(, of the com mod i t y, 2) iekntify resea rc ha ble issues, 3) assess I ITA 's compa ra ti ve ad va ntage, 4) d c termin t' appropria h ' research mc thod o logy, 5) estima te the resources need ed to ac hi eve researc h res ulls a nd a d optio ll within the expec ted time fra me, 6) d e fine the linkages be l ween resea rch on the commodit y a nd Afri ca f~H-min g syst(, ms, a nd 7) assess p riorities within a nd across resea rcha ble issu es a t varying funding levels."},{"index":5,"size":115,"text":"Ea rl y in our dclibcra tio n:5 on the struc lure a nd scope of the S tud y, we mad e two ass umptions o f fund a mental imporla nce: First, the Stud y shou ld be concern ed prima ril y with resea rc h re ie vantto sma ll la mi ly fa rms in Ali•ica . Second , the prima ry geogra phi c area o f rocus for th e Stud y should b(' th e lowla nd humid a nd subhumid regions o f A li•ica. These twO assumplions, endorsed b y the Boa rd ofTrustct's in April 1986, wa rra nt a mplifica ti on here."}]},{"head":"Generation of Technology for Small Family Farms","index":3,"paragraphs":[{"index":1,"size":276,"text":"A .. <o:; a ma tt er o f po licy, I1TA 's resea rc h o bj ecti ve wil l be to increase the producti vity a nd incom e o flh e sma ll African larmer. Our ul tima te targe ts a rc progressive fa rm fa mili es whic h a re commiucd to improvl'd ma nagement practi ces a nd which hav(' sufficicnt la nd a nd resources to produce a surplus for the ma rk et. These a lT (he (ilrmcrs who, by inc reasing commercia lization of their opera tions, can adopt the improved techn ologies that \\vi ll be the driving force for agricu ltura l change_ U TA can do little directl y to improve the welfare of f~1rmers unab k LO adopt improved management practices_ Our best instrument for reducing their povert y is increas ing agricultura l producti vity of the small-sca le progressive fanners in the regio n and , thereby, demonstra ting innovations and stimulating employment and higher incomes for al l. Given the ra pid population g row th and its ever increasing effec t upon th e degradation of fragile African soils, in creasing the productivity of famil y farms must be at the heart of improving Aft-ica n agriculture and food production. But there arc powerful biases that discrimin atc against the fami ly fa rmer : I) na tiona l policies and progra ms that squeeze thelll in favo r orIarge-sca le commercia l enterprises, a nd 2) research institutes that dC' sig n mociLTn technologies that a rc not appropriate fo r traditional, African family f~tt-ming systems."},{"index":2,"size":118,"text":"The contribution or resea rch to grea tcr rood production during th e coming decade must come large ly fro m improved va ri eti es d eveloped by commodity research programs. But th ere will be no payoff unless these varieties arc producti ve in the rea l world of the Africa n farmer. A grea tl y strengthened rarming systems ori enta tion througho ut I IT A wi ll be required to assure tha t the technology we generate is within the managemcnt capability of the fa mil y farmer. Fa rming systems research is, in a sensc, just the serva nt of the commodity programs; but its close in volve ment is essentia l."},{"index":3,"size":61,"text":"The Strategic Pla nning Study wi ll illumin a te areas in whi ch there is an economi c trade-ofT betwecn in vestment in technology for sma ll versus large-sca le fa rmers. In making program decisions, we wi ll giv(' prefe rence to those strategies that arc aimed a t improving the producti vity or the smail fam ily farm."}]},{"head":"Africa Focus","index":4,"paragraphs":[{"index":1,"size":121,"text":"For purposes or the Strategic Planning Stud y, we ass ume that II TA shou ld p lace specia l emphasis on improving the productivity of fa rming systems in the lowla nd humjd a nd subhumid tropics o r Arrica. IITA has a lmos t 20 years or ex peri ence d ea ling with these ecologics, a nd fa lling per capita food production ma kes them areas of great concern. Th('se ecologies, roug hl y cong ruent with West a nd Centra l Afi'ica, conta in ha ir th e population o r sub-Sa hara n Africa. This enormo us, diverse a nd co mplex region call full y cha lknge I ITA's scientifi c ca pabilities ."},{"index":2,"size":97,"text":"T his interpretalion of our forma l ma nd ate in no .way conflicts wi th the int ern ationa l character or I ITA . \\\"' e have broader res po nsibilities in Africa -and o ther contin ents tha t W(' will continue to respect. \\\"' e will actively promote those commod iti es for which we have a wider ma ndate in a ll of sub-Saharan Afri ca, but beyond Africa w(' will normall y share technology and knowledgt<>o nl y by means or germplas m excha nge, pub lica tions, a nd training."},{"index":3,"size":93,"text":"Withillth cspccia lt argct Africa n ecologies, IITA cxpects to take the lead in resea rch on a ll iLS cro ps. Core resou rces wi ll be used to carry out the ful.! range of research. training and outreach acti vities here. We will int ensify efTorts to und ersta nd the fa rming systems of these ecologies in ord er to improve the producti vity of our crop improvement progra ms a nd to contribute through more basic resea rch to bell er resource manag(' mcn t and conserva tio n."},{"index":4,"size":122,"text":"In response LO the crisis of African agriculture, ma ny interna tiona l agricultura l research centers arc developing new programs lor Af'rica. This is admi r~b l c, but the genera lity of the CCllt\"TS' mand a tes creall'S potential {o r mi~und ers talldin g, confusion to the h'uders of na tiona l resea rch systems, and possibl y wastcful competition. I ITA is centrall y positioned to encourage l'Volulion of the centers toward a coherent system with consistellt prog ra ms in Afi•ica . But I rrA can play this role ill inHTC('l1tL T coopera tion onl y if we first de lin ea te' our own priorities in a way that is clear. realistic, a nd \"vorka blc."}]},{"head":"Conclusions","index":5,"paragraphs":[{"index":1,"size":97,"text":"VVe ent er 1986 constrained by a budget lower in rcallcrms than in 1985 a nd tht pros pect for finan cia l stringency throug h the end of 1987. Nevertheless, we arc opt imistic about the flIlure. \\Ve arc instituting majo r improvements in management control and fin a ncia l planning syslems for lhe I nSlilu le. The lig hl budgel reinforces lhe process of progra m consolidation a nd priorit y-setting under way. As a consequence ofth c Strategic Pla nning Study, I ITA should emerge as a stronger and more rHcctive organiza tion."},{"index":2,"size":69,"text":"Nloreovc-r, a vision of the Illturc is emerging that includes emphasis upon the sma ll fa mil y farmer, increased focus o n ecologies where r rrA has a comparative ad va ntage, o rientation of I ITA commodit y prog ra ms toward the Illrming syst('ms of these ecologies, a nd commitment to coopera tion wit h o ther int lTnationai Cl'nl<TS and nationa l agricultural research systcms."},{"index":3,"size":45,"text":"(ITA is a scientific cntl'rprise an imated bya hig h socia l purpose. The above elements sugges t a philosoph y and set of va lu es that ca n be the basis for mo\\'ing \\'igorously a head on o ur cha llenging miss ion."},{"index":4,"size":170,"text":"In Up land Production. Sys tems : Th e' upland resC'a rch tea m rocllsed on so il a nd cro p managemen t systC' ms basl. :d on cassa \\•a , yams, SWl'l' l po ta toes, ma ize, u p land ri ce, cowpca s, a nd soybea ns, In t he fOrt'SI zonC' . thl' el11phasis was a ll rOO t c rop based systc ms. sava nn a a reas o n cerea l/ leg umC' based systc ms. Hig h prior ity was assig n cd to so il cOl1sern ll io n and bi o logica l improvc-melll oesoil produCl ivit y. Thus. s w di cs o n CO\\•(' I\" c ro ps a nd p lan led fa llow and their eITC:cts on l1utri c l1t recycling ; soil eros ion cOl1tro l, b io logical ni trogell fixation , a nd so il bio mass a c ti vit y con ti nu ed to Ill\" a major th r ust."},{"index":5,"size":108,"text":"Fo r the non-ac id or hig h base Sta LUs Alfiso ls a nd (nccpt iso ls in th e sub-humid a nd humid zones. resca rch r('su Its ha \\Ie showll I ha t the no-ti II 111 a ize-cowp ea -IUUCIIl1(l rounion system a nd a lle y I:o. rming w ith L eu((I('II{I a re ab le 10 sustai l1 hi g h le vels of ma ize a nd cowpea yields over a lo ng pe ri od w idlO ut ITwTting the land to \\•a r yin g pe riods o f\" na LUra l or p la nted r~dl ow ."},{"index":6,"size":84,"text":"On the coa rsc-t ext u red, we ll-drain ed ac id ic L it iso ls in th e hig h ra in fa ll region o f SO l! th ern ~i g(' ri a. resu its from CaSS<lV3 tillage experilll ent.s ind ica ted that a no-ti ll sys tcm with che mi ca l weed contro l produ ced lU bel' yields cq ua 11 0 those o r convC' l1ti ona I a nd slr ip-I ill agc nwthocls."},{"index":7,"size":112,"text":"I n mixed cropping t ri a Is o rcassa\\la / m ~l izl' a nd cass;) va /cowpens conduc lI.:d 0 11 an . \\I fisol a t I bad a n . ~i gC'r i a, the sizt.: of cassa nl po pu la Lio lls had no ad'Trse effec ls o n maize r ic-Ids, but a hi g h po pu lat ion of spread ing-type ma ize redu ced caSS3,•a yie ld. T he 1110S t d es irab le p la n Ling pa tt e rn for cassava /cowpea mix ture was to p la nt bo th crops in the sa 111 (\" row."},{"index":8,"size":240,"text":"Resea rc h 0 11 wced man <lgclllent ro r upl and c rops c mp hasized tillage mct hod s a nd li ve mulch. \" •C'cd bio mass in ma ize had a n in verse rela tionshi p wi th intcnsit y of tillage o pe ra ti o ns. H er b ic id e dTi ca cy d ecl ined with redu ction of tillage intensit y. \" •rcd cOl)trol was k ss l,ne'c tivl' with }O\\\\'\" r:llcS or her bi c id e a pplication in no-till co\\\\'pca s :l nd soybC'a ns than in con ve ntio na ll y till ed lI\"l\";:Il ITl(' n ts. In a 10 ng-tC' r mli \\'c mulch tri a l a t (ba d a n , plo ts w herl' li n mu lc h (i. e. Pso/)hormjJIIs /)aIIlSl,-is) was g rown for th e past fi ,•c yea rs yic ldcd Illore ma ize t.han til(' conti nu o usly c ulti va tt'C1 no-till o r p lowed plo ts. T his was a ttribut ed to less wecd infes ta ti on and hi g her soil o rga ni c ma tter a nd biomass ac ti viti es in the li ve mulc h plo ts Resl'arc h o n cOl1 lro l or the nox ious wl'eci im/Jcrala (lIliue/ri(({ in a sub-humid eco logy was initia ted in 1985."},{"index":9,"size":75,"text":"Mic rob io logy s tudics conduc led during the yea r included bio logica l nitrogen fixaLion in cow peas, lillie/ilia a ncl 5\\' 'I'e('1 p01a toes, m yco rrhiza l infecuons of sweet pota toes i 11 d ifTcrcn t soil types , a nd c hanges in micro bial po pula ti ons and aCl ivili cs fo llowing fo res t clea ra nce a nd culli va ti on ."},{"index":10,"size":54,"text":"R csuhs (i'om th e bio logica l nitrogen fixaLi o n stud y showed tha i nitrogen yield of ea rl y ma lUring cowpeas was less tha n la te ma wring ind etermina te va ri eties. Cowpcas d o not contribuu: nitroge n to ma ize inlcrc roppcci widl cowpeas."},{"index":11,"size":128,"text":"1 n agri c uhura l engi neering , on-fa rm eva lu a ti on of improved lOols a nd implemen ts for s ma ll fa rms continu ecl. These includ e ro lling injection p la nter, fertilizer a pplica tor, ma ize thinn er, a nd ro\\v ma rk er. R es ul ts fro m a tillage experiment a t Ibaclan showed th a t para plow once a yca r prod uced significa ntl y hi g her ma ize yield than continu ous nO-lill a nd conve ntiona l tillage trea tment.s. This \\-vas rela ted to low pcne tro meter resista nce, hig h wate r infilt r<:llion , a nd low incide nce o r will.ing during dry spells."},{"index":12,"size":125,"text":"Wetland Production Systems: Sub-Sa ha ra n Africa has over 30 million hec L a res o f potenti a ll y a rab ic \\vctl a nds 1 so mc o r whic h a re sources or va ri ous produ c ts tradiliona ll y ga thered rrom th e wi ld , yam /a nd or COCOY3 m c ultiva ti on o n la rge mo unds, a nd dry season vegeta bl e produ ction ; approximatel y 3 milli on hecta res orthe \\< vc tJ a nds a rc presentl y und e r rainred low la nd ri ce culti va ti on a nd less than 500,000 hectares a rc uncler irriga ted paddi es."},{"index":13,"size":166,"text":"Research on sma ll inland va lleys is a imed at d eveloping both upla nd a nd va lley bOllo m as a w ho le (a rm unil. Beca use o r l.he lac k or ap pro priate soil a nd waLC. T ma n agem cnt tec hn ologies in th e va lley bot to m (wetland ), many ra rmers have a lloca ted more la bo r a nd resources to the produc ti on o f cro ps in Lhe upla nd . 1 n la rge wetland areas. suc h as large ri ve r flood pla ins a nd coasta l d eltas where ra in(cd o r irriga ted lowland ri ce pred o min a te, resea rc h priorit y is accord ed to soil fenility m a nagement ;:md la nd preparation for rRin red a nd irriga ted low la nd ri ce, a nd for post-ha rves t engin eering."},{"index":14,"size":219,"text":"During 1985, research on sma ll va lley d evelopm ent was sta rted nca r Bida , N igeri a a nd rvl a kenni , Sierra L eone in collabora ti on with the lnternat iona l La nd R ecla ma ti o n Insti tut e (l LRI ) in the Nctherl a nds, L a nd a nd W alc r D evelopm ent Di vision (LWDD) in Sierra Lcone , Na liona l C ereals R esea rc h InsLitute (1 C RI ), a nd Bid a Ag ri cultura l Develo pmenl Proj ect ( BADP) in N igeria . H ydro logica l studi es were initi a ted in rOlIr be nc hma rk vRlle ys in both countries aJlcl o n-fa rm agrono mi c tria ls conduc ted in several inla nd va lleys nca r Bid a on rn a ize/sorg hum intcrcropping in the upla nd a nd ri ce in the va lley bo tto m . Prdiminary rcs ul ts indicate tha l far mers liked the improved shon maize varie lY (TZESR-W ) beca use o r its ca rl y ma turit y, resistance to s trea k virus, a nd resista nce L o lodging during heavy rai n storms."},{"index":15,"size":87,"text":"Results or 10 o n-rarm tria ls on ri ce (fa rnH' r ma naged ) in the va lle y botto ms showed tha t with con LO ur bunding , rertilizer, a nd weed conn'ol , bo th th e latr maturing loca l va ri ety a nd the improved ea rl y ma luring vari e Lies ( ITA 306 and FARO 29) gave co mpara ble padd y yield o fabouL 'It / ha in the sa nd y h ydromorphic soils."},{"index":16,"size":81,"text":"In troduction o r simple ha r ves ting a nd threshing too ls such as the serra ted sic kl e a nd th e ma nua l ri c(' thres her was readil y accep ted by loca l fa rmers. However, mo tor-drive n implem cllts (slIc h as the turt le p low) will have to overco me ma ny soc io-econo mic conslra ilHs before th ey can be adopted b y loca l farm ers."},{"index":17,"size":95,"text":"Agroforestry and Plantain R esearch : Agroforcs try is a n impon a nt com ponenL in farm ing sys tems in the humid tropics no t onl y in terms of nutrient recycLing a nd soil conservation bur a lso in suppl ying food a nd firewood to sma ll fa rmers a nd ensuring overa ll susta in ability of productio n. Thus, agrofo res rry research a l II TA focuses on a lley crop ping a nd th e improvement of mul ti-story co mpo und (ho mestead ) fa rms."},{"index":18,"size":36,"text":"The Lellcaena a nd GIi,.icidia a lley cropping syslems o n non-acid soils (A lfisols) d eve loped a l I ITA have ga in ed increasing acce pta nce by na tiona l resea rchers."},{"index":19,"size":82,"text":"O n the stro ngly acidic U ltisol (T ypic Pa leudull ) a l I ITA 's hig h ra in fa ll Sta lio n a l Onne, Nigeria, severa l shrub species we re eva lua ted in association with cassava . Preliminary results indi ca ted tha t Cassia siamea pla nted in 8 m a ll eys gave the highest cassava yield . Cassava growth a nd yield were d epressed when a lley cropped with Gille/ina."},{"index":20,"size":61,"text":"During 1985, both fa rmcr-and-resea rcher-ma naged a liey cro pping on-fa rm tri a ls with L Cl/caclla leliCOCIJ/Jhala a nd Gliricidia scjJium were esta blished in co lla bora ti on with I Le A a nd na Lio na l research institutions in Nigeria a nd in severa l \\Ncst a nd Cenlra l Africa n countries ."},{"index":21,"size":193,"text":"This yea r pla nta in /ba nana resea rch beca me one of the core act iviti es in the Fanning Systems Progra m. Nlaj or activities were centered a ro und increasing producLi vit y of low input production systems a nd increasing th e suppl y of pla nting ma teri a l to aid expa nsion of production. Th e major part of the research was done in na tiona l resea rch institutio ns throug h [he \\'Vest African Regiona l Coopera ti ve for R esea rch o n Pla nta in. A summa ry of the research results: (1) Sma ll fa rm production was more profit able tha n medium or la rgesca lc; (2) no ne of the p lanta in culliva rs screen cd were resista nt to black siga toka -th e d isease threa tening pla nta in produ ction in \\\"' est Afri ca; (3) planta in grown with coffee \\-vas no t severel y infes L ed with the bana na \\vecvil ; a nd (4) in vitro-produ ced pla nts a ppeared morc vigorous tha n others ."},{"index":22,"size":112,"text":". Mos t pla nta in culli va rs did no t lose mo rphogenetic po tenti a l a ft er six cycles of multip li cation in meristem culture, a nd the mul tiplica tion po tenti a l of some exceed ed 100 mi ll ion in one yea r. Th e new techniqu e for ra pid mu ltiplicat io n of pla nta in in the field is a sig nificant improvement over current practices. T ests for aberrations in p la nts from mcristem culture mulliplica tion showed less than 1 0  0 abnorma li ty. Ther(fore, this techniqu e ca n be safely used ."},{"index":23,"size":108,"text":"On-Far1n R esear ch: D eve lopment of resea rch methods a nd testing of lIT A techno logies were conducted in three pi lot a reas in different ecologies in Nigeria in coopera tio n with na lio na J institutions. On e fu ll year of on-fa rm testing was complet ed in the sava nna a nd lra nsitio na l zones wilh a ra nge of technologies, including va rieti es ofrh e traditiona ll y g rown food cro ps, fenilizer use, a nd a lley cropping. The pi lo t area in the forest zone was idenLified a nd surveyed in 1985."},{"index":24,"size":83,"text":"Socio-Econo1nic Unit: SL a ffm embers of this unit provid ed socio-economic inputs into the resea rch acti vities of the crop improvement progra ms, ex pa nd ed the socio-econo mi c assess ment for on-farm resea rch ro facili ta te the tra nsfer af illlproved technologies, initiated new proj ects on food crops utiliza tion and nutritio n (particula rl y o n soybea ns). and co mpleted a n exp loralOry stud y o n co mpound fa rms."},{"index":25,"size":116,"text":"A task ro rce deve lo ped a n inu.:g ra tcd pi lo t progra m with the Ke rsey C hildren 's Ho me a t Ogbo mos ho, N igeri a on soybea n produ ction a nd utilization as a nutritio n interve ntion stra legy ro r hea lth imprQvt' mcnl. A socio-economic surn 'y a mo ng 386 o rits cli entele showed A syslema tic efTo n v,Ias mad e during the yea r to in crease the number or wo mcn in Il rrA 's produ ction training a nd post-TraduaLe n 'sea rch and streng then colla bo ra Lio n with na Lio nal socio-cconom..is ts."}]},{"head":"Conferences} Workshops, and Training Courses:","index":6,"paragraphs":[{"index":1,"size":94,"text":"The Fa rming Systems Progra m coll a bora ted with na tio na l Cenlers in o rga nizin g three inte rna tiona l conferences a nd /o r workshops on: la nd cJea ring a nd d evelopment held in Indon esia, \\-ve tland uti liza tio n fo r ri cc produ ction in tro pica l A(i-iea held a t I rl\"A's headqua n crs, a nd planta in a nd cooking ba na nas multiplica tion and uLili za ti on held in I vo ry Coas t."},{"index":2,"size":56,"text":"Five tra ining courses were conducted in 1985 ror nati onal researc h and ex tensio n work ers in Afi•ica: soil /wa lcr constTva lio n a nd Lillage systems, weed manage me nt , a lley cro pping. so il a nd plant an a lys is, and on-fa rm resea rch method s."},{"index":3,"size":52,"text":"In the f ollowing pages, a fe w notable r esear ch hig hlights during the year are briefly described. More comple te info1'matio1l on these topics a1ld those 'Inen tioned in this Executive Sunl, 'mary can be o btained by requesting the Annua R eport of the Farming Sys tems Prog,•am."},{"index":4,"size":84,"text":"Fallow Management for Soil Fertility Restoration and Fodder Production in Rwanda B ecause of a severe shortage of arable land in Rwanda , fallow periods between c ultivation phases have b een progressively reduced to one year or less. Consequently, better fallow management practices are n eeded to help restore soil fertility in a short time, and o ne lTIeans is to plant suitable legu minous and oth er species that can provide green manure, soil cover mulc h , and fodder for animals."},{"index":5,"size":120,"text":"SciClllists in th e fannin g sys lt: : : ms resea rch project a t K a ra m <l ha ve eva luated several legumin o Li s species for biomass produc tion , soil surface protec tion , abilit y \\0 sllrv in' during the dry seaso n (J UI1 (~S ('plc mb n), and case o f' es tab lishment a nd blending of ha rvcs lcd lOpS as green ma nure into the soil. Tri a ls with rour species -Croln/arill sp (sunn hemp), Alumua pruriclIs va r. ulilis, Cajllllus Wjll ll (pigeon pea), a nd Sesbanin scbo n showed that they a rc a bo ut eq ual in biomass production Crable I )."}]},{"head":"Sig nifi ca nt increases","index":7,"paragraphs":[{"index":1,"size":92,"text":"In g ra m yicld of succeeding crops wcre obta in ed du c 1O inco rporation o r g ree n ll1at eri a l rroll1 twO 22 lrguminous cover crops in co mpa riso n with the tradi ti ona l practice or na wral fa llow. A lso, plOlS previously pla nted to S\\v('c t potatoes (tuber yield 7.5 t/ ha ) gave a rel a ti vely hi g h g rai n yield o r subsequ ent soy bea n / ma ize illlcrcro p (Table 2)."},{"index":2,"size":143,"text":"Fas t deve lo pment or vege ta ti ve cover is necessa ry to prOtec t th e so il surrac e rrom erosion . Sunn hemp (Grolalaria sp) raled as th e best species fo r ea rl y ground cove r (T able 3). Scshania sesba n was vcry slow growing and LOok much lo nger to cover the so il. M aintenancc or ground Co ve r during th e dry season and at the beginning o r rains in O ctober is essen u a l to Visitors to the fa,.,n.;ng syste ,n.s experi' ,n.e nts at K arallla~ R wa nda see different legu minous species (including S lUln hemp and m.ltcu lla) be iPlg evaluatedfor their ability to protect tlte soil s urfa ce 3 s 'lH-vive during tlte dry period, mid p\"ovide fodder for ani,nals."},{"index":3,"size":48,"text":"redu ce soil erosion. Cajal/Ils cnjlln (pi gco npca ) was the most droug ht resista nt d uring th e dry seaso n ; sunil h ClTlp rat\"cd st•co nd . . \\ll/tIIl/o sheds a ll its leavc:s during th e ca rl y d ry season."},{"index":4,"size":410,"text":".\\I ixing 50 0 0 sunn hemp wi th 50 0 0 g rasses im proved the q ua lit y of fodd er a nd in creased th e li vewcig ht ga in of goa ls. Bo th 6-mo m h o ld and IS-mo nth o ld goats gained 2 kg in 16 d ays when fed th e mixture co m pa red with on l y •~ kg fo r lhe 100 0 0 g rass ra tio n . Trad itio na ll y, the majority of a nima ls ra ised in sta lls a rc fed grasses, a nd th ere is a n ac ut e sho rt age of thi s feed a nd o th er fodd ers througho ut til (, co untry. T hi s sho rtage ca n be ca sed b y planting legumin o us species o n fallow land a nd using th em lO su pplement the grasses for an ima l fel'c!. H owever, w hl'n th e fa llow species a rc cut a nd used for this purpose, a bo ut ha lf of th e nitroge n fix ed bi o logicall y will be expo rt ed fro m th e fi e ld. th ereby redu cing th e extcIH of rej uve nalio n of th e so il a nd fertili ty res LOrario n . Th is ca n be o nse t by th e ma nure li'o m the sla ll-red an ima ls being rCI LIm ed 10 th e sn me field .          In intcrvjcws, ranncrs sa id th at making Ihe ricl g('s \",ith til(' d onk ey model ca used thelll no fa li gue prob lems and lhal lill\" donkey o ft t ll lin'd out bcron. ' th e oper;ltor, \\\\' hen asked ho\\\\' man y hours per da y their donke~ could make and tic ridges their a nswers ran gt'd from I! to 3 ho urs. They poinled o ut tha t thl' com bin ed aC li\\'ilics of ridging a nd join ing the m with lies were LOa mu c h work ro r their do nk eys to d o o n a reg ula r basis. Therefore, they wou ld sepa ra te th e two activities ir they were to con tinu (' thi s cultura l practice."},{"index":5,"size":120,"text":"Full l'\\'a lu a lion or t hl' lrSIS conducted in 1985 had not been co mplcted at th is wri ti ng, but prelimimtr) co nc lusions indicatt' t hat ani ma l powe r ca n be used ror making ti ed rid g('s. The major limita ti o ns ort he equ ipment a re rd a ted to t ht' weight an d It:ngth panicula rl ) in the cas(' or th l' oxe n mocie l) and to the hand tripp ing mec hanism adjustments and cab le lire). Bo th devices will be modifi ed an d it is cxpccl(.'d th a l the tesling or imp ro\\'l'c\\ models wi ll con tinu e."},{"index":6,"size":44,"text":"Fanne r's a tte nd a fi e ld d ay to see a d e nlo n s trat;on oJ\" do nkey-powered tied ridg ing implem ent deve lop ed by the liT A-SAFCRAD resea rc h pr'og r'um i\" Bw'k ina F\"so."}]},{"head":"-_J","index":8,"paragraphs":[{"index":1,"size":19,"text":"Afarmer-nwnaged on-farm trial of lowland rice in a s mall inland v alley (fadanw) near Bida, Nige ria ."},{"index":2,"size":74,"text":"On-Farm Research in Small Inland Valleys in Central Nigeria I n c r eased dernands for ri ce as a staple food in sub-Saharan Africa requires more intensive use of s uitable wetlands for rice produc tion. West Africa has over 30 million hectares of wetlands with about one-third of this area occupied by small inland (or stream flow) valleys. The r est is classified mainly into deltas, river floodplains, and overfl ow valleys."},{"index":3,"size":106,"text":"In coll aboration with the Bida Agricu lrural D evc lopmc11l Project (BADP) and National Ccre-a ls Research I nstillilc (NCRI ) in Nigeria , Land and \\VaLer De velo pment Di vision ( L\\VDD ) in Sierra Leone, and International Insdtute of Land R cclam3uon ( ILR1 ) in the Nctherlands, rITA initiated the \\IVest Afri ca n \"\"'ct la nd Uti liza tion Research Projec t. lLs main objective is to d evelop low illput soil , wa ter, and cro p ma nagemcl1( techn ologies that will enab lc sma ll fa rm ers to cuili vate the va lleys more in tensively."},{"index":4,"size":123,"text":"Two inland valleys near Bida in th e subhumid region of Nigeria were selected as bench mark research sites a nd initial field wo rk slartcd in late 1984. Maj or acti viti es in 1985 focused first on the characteriza ti on of the sites in terms of soil ) water, cropping sys tems, a nd socio-economic environ ment : th en preliminary studies of wa ter ba la nce and on-farm tesling of imp roved crop varieti es, soil ma nage ment practices, and sma ll farm too ls a nd implements. Far mers in the area culti va te bOl h th e upland a nd va lley bo[[om as co mponellls of a who le fa rm un it."},{"index":5,"size":241,"text":"t n the va lley botto ms, rice grows in t he ra iny season where the soil is norm a ll y sa turated or flood ed . In the d ry season, swee t potatoes, earl y manu'ing cassava a nd vege ta bles grow on mounds in t he va lley bo lto m where soil mo islUre is Slill available. I n the uplands,     Crop prod uction practices in th e two va lley depend entirely on hand labor and th e usc o small too ls -a maj or handicap 10 increase cropping ilH cnsit y and producti vity. Also, ther is usua ll y a labor shortage d uring peak period of land prepararion, pla nting, weeding, an harvesti ng. Low yields of major food crops ca be attribu ted to severa l co nstraints : in ri c produ c ti o n , poo r o r no wa te r conlro ineffi cient la nd prepara tio n, weed s, iro loxicil Y from seepage water, poo r soi l fertilit low crop d ensity, and low yielding varicties; i the upla nd cropping systems, poor soil fertililY UPLAND 7 t..s polol0. erra ti c ra in fa ll. dro ug ht strtss. infesta ti on of so rg hum o r ma ize by Striga (<:\\ pZ1rasitic weed ), cassava mosa ic disease, a nd low yieldin g \\'a ri cties."},{"index":6,"size":53,"text":"Fa rming ac ti vitil's in til(' upl a nd result in ri cl' pl a nting de lays in the va ll ey bo tto m. Farmers p hnll th eir rice in Au gust o r Septe mber w hell th (Tl' arc few ac ti\\'ilics in the upland. A lso."},{"index":7,"size":264,"text":"plan ting of second seaso n crops anC T ri ce in th t' \\'a ll ey bO llo m is cil-bYl'd IX'ca use f3rlll t' l\"s a 1l0 C3l<' mllc h of th eir la bo r to posl-ha n \"('s t a cu vll lt'S. These co nstra ints a r(, bein g addressed in th c desig n a nd testing of tec hno logics fo r fa rm ad o p ti o n, in c lud ing th e introducti o n of new c;:trl y rice : va rieties in lh l' lowland tha t matLin' befo n ' so rg hum is har-\\I('s tcd in th e upl a nd, R('sults of 10 o n-fa nn tri a ls in th e lowland dur in g 1985 showed t ha t under fa rm ers' trad itio na l ma nage mcnt (tra nsp la ntin g a nd bundi ng ) th e improvC'd ri ce va ri ety ITA 306 gavl' hig her yield than a no t her improved va riet ), ( FARO 29) and tIll' loca l chec k variet), Cfa b le 4) . The loca l chec k is ;) mixture o r s('v(' ra I i mpro\\'ed va rict il's fro m previo us in trod uctions. L ndcr i mprO\\'td ma nagc mclll Il ranspla l1ling. bund ing . ch(' mi ca l w('cd co nt ro l. a nd fertili zc r , lhe t hr('(' \\'ari CLk's prod uced ahOlll th e sa me yield ."},{"index":8,"size":509,"text":"Farmers respo nd ed 1~l\\' o rab J )\" to th e illlpron'd n lriclY ITA 306 rn;)ini y IX'cause of its ('arly !luluril), -106 da ys a tilT plan ting com pared wilh 123 da ys lo r th e loca l chec k.  LOll g-tl'l'l1l alley c ro ppi ng ha d a pos iti n (' fltc t on ma ize g rain yie ld. \\\\' ith or Wil h OlI n itrogen applica lion l1l a iZl' yie ld in the fifth c ro pping yea r g row n u nd er no lill ag(, wai hig hc r th an in the cOlllro itrcal lllCIlI ( Fig ure 3 In th e co n tro l p lo t. ma ize yie ld peaked w ith an a pplica ti o n o f 90 kg N/ha . T he yield w it h L t' u({f('1lf1 :\"I lky croppi ng was signifi ca ntl y hig her wit h half Liw ap p lic'lli on of nitrogen . This ind ica tcs t ha I not o n ly s lI ppl~' of ni trogen but a lso o th e r impron'l11 el1\\ s in t he soil through a lil-y c ro pp ing ma y p la Y:l mon' im portant role in ensuri ng hig he r ll1 a izl' yields on <t d egrad r d Alfi sol.   In association with th e other fi eld syste ms (Figure 4), co mpound farms, w hi c h arc fa irly stabl e agroccosyslcms of varying co mplexit y, help to minimize seasona l periods of food shorlag c. AI the saine lime, th ey ensu re reaso nable levels of produc ti v it ), for a ra nge o f foodstuffs wilh ve ry little o r no risk o r cro p fa il ure. The co mplex agroccosYSICI11S of co mpo und farms in tro pica l Africa ha ve ha rd ly bee n studied so as lO u nci(-rst3lld their composi tion J S(TU Ct ure J interactio ns a mo ng co mpo nents, nUlI'itiona l, econo mic, and overa ll socio-cultural imp0 rl an ce, \" is o nl y throu g h stud ying and und erstand ing them that it will be possib le to make worthwhile improve mellls.       c hildn: n co mpared with -1-0\"0 in the rl\"):.l of the <;am pll', • Polygamy <llonl\" was nOl a sig nifinllli f<lcLO r in c hi ld loss or m;dno uri silnwl11.  5 \\\\' ilh a bo ut .10 0 Q protcin and 20 0 0 fat. soybea ns provid e a highly nu Lri lious food which ca n be used as a mi lk su bs titute. (Abo ut 40 0 (} of th t., ma lnou rished c hildre n trea ted are all e rg ic La eO\\\\•'s milk ,) A lso, soyh ea ns ;HC add ed La c{\" real weaning food. 34"},{"index":9,"size":30,"text":"Soybean p a~tl' m ade in till' hou: .. e with w ho k bea ns form ~ tlw basis for mall~ rt.'ci pl's lIsed a t th e clinic."},{"index":10,"size":43,"text":"SoylJl'an produc ti o n techno logy matc hes th t• n:so urc<:sof's m:dl-sea k fa rm crs in th l' area with lh e principal inputs being good secd of a n adapted varie ty and useful ill for m a tion."},{"index":11,"size":225,"text":"Clin ic a nd I ITA ~t a fr I1wmbcl's wOI'kl•d togctht r duri1lg 1985 with tht.'st.• resu lts: ( I ) land c kan'd and a d e mo nstrat ion plo t of' soybeans p la ntcd a t the clin ic with p la nting li mes sta gg('J'(\"d so the mOl hers of' paLicnt, s co u Id DC\\T lop mCIlI o f ea rl ie r ma luring lTI :1 izt' va rie ti es fo r this a nd other p urposes has bee n an ilnpon a n t goa l for th e past eig ht yea rs. A p hysiologica l draw back of ca rlj er J11 <ll urit y is t ha t ) since the vege ta tive period is shon er. all the pla lll pa rts including th e ca r a rc sma ll er t ha n la tcr ma tu ring maizl'. T o ob tain ma rc informa tion a bout th e ma rket for fres h ea rs of ma ize and d eter mine t he agrono mi c a nd eco nomic impac t of ea rl ier ma tu ri ng ma ize va rie ties, studies we re u nde rt a ken during 1985 in villages ncar I ITA headquarters."},{"index":12,"size":170,"text":"The on-far m research compa red loca l la tcm <1 lU ring maize vs im proved ea rl y ma tu ri ng J11a iu (T ZES R-\\'\") illlercroppt d wit h a loca l cassava va riety. Superim posed on the far mer ma nage men t of th_ is co mpa rison we re di HC:relll The key faelOr in 3 n econo mic a nalysis o gree n rnaizc production is the \\•a lu{' of Lhc ear whi ch is subj ec t to ma rk ed fl uctua ti on ali th season progresses (.Fig ure 6). It was d iffi cult t es ta blish a price for gree n ma ize before j un a nd a fter Sep tember beca use the vo lullll' on th ma rke t was small a nd supply irreg ul ar. Price in ea rl y J line a rc vt ry hig h beca use of th o kgj h:l  sl'nTit)\" of thl' food shonage."},{"index":13,"size":116,"text":"As mo rl' fanrH'rs lJl'gin (0 harvl'st lll('ir g n '(' ll mai ze ears, the pri ce d eclines rapidl y, and in mid-Jul y the ITI;lrkl't is noockd . Artl'r th e first m a ize crop has bee n ha rv(•s tl'd. the price o f' maize agai n incrl'ases, The lutl' Sl'3son price inCl'f'asc, Wh(,l1 mol'(' suppli es of ot her food crops a rc ava il ab le ) is basf'd on t wO fa ctors: a I'l'du c('d suppl y dul' to thl' ag ro llumic d iffi culti es of g rowin g a latc-pla llled mai z(~ crop and th e dcmand for las t\\' maize ('3 1'S,"},{"index":14,"size":110,"text":"In th e on-far m tria ls, TZESR-\\\\' was h.u\\'cs ted 70 days after piallling and th e loca l v:H iCl v two w('ch lalCr. TZESR-\\,V was harvl'st(,d heforl' the s harp pri ce d('cline ; thel'efol'e, it had a hi g her va lu e pCI' l'ar eV('1I though the cars were s ma ll er Cr ab le 6) , The \\'a ltl e per ca r is the major factor determining n('l benefit in the panial budget analysis, The pa rti a l budge t does not include a ll th c COSlS of production , hut it Ca n be used to d etermin e' "}]},{"head":"I.","index":9,"paragraphs":[{"index":1,"size":2,"text":"2. 3."}]},{"head":"I.","index":10,"paragraphs":[]},{"head":"5.","index":11,"paragraphs":[]},{"head":"6.","index":12,"paragraphs":[{"index":1,"size":51,"text":"7.          or inorganic nitroge n rcrt ili zer. .\\ lso. lhes(' s lUdi es have s hown thal lhere is more ea rth worm ac ti vit y in the li n' mulch plots th a n in the conven ti ona l a nd no-tillage sys tem p lo ts."},{"index":2,"size":116,"text":"Ano th er beneficia l eHect of li ve mu lc hes is th e add ition of ni trogl' n 1O th e soil for use by a food crop. Rcs('arch res ull.s show th a t a hhough psopho inlerp la nt ed with maize competed with th e crop fo r nit rogen d urin g the first twO yea rs, it bega n to suppl y a bout 14 kg N/ ha (l fter that. A two-year pso pho fa llow supplj ed over 40 kg N Iha to a ma izt.: crop in its fi rst yea r of usc as a li ve mulch (Fi gure 9 lcrl ) ."},{"index":3,"size":45,"text":"Oll e of th e und es ira ble sid e e!Tec ts of illlcilsin' culti\\'a ti on in the Lrop ics is th c increase in weed pn:ssure ca used by short bush fa ll ow periods of two to th ree yea rs."},{"index":4,"size":134,"text":"The popub ti on ofw('ed seeds in th e soil after four yea rs of tillage and li n' mulch wa!> co mpared with the original seed pop ula tion at th e b('ginning of the stud y. Resu lts show that aftcr fo ur yea rs of ma ize produ cti on (tWO crops per yea r), weed seeds in t he so il d ecreased b) over 80 0  0 in th e lj ve mulc h plols beca use Lh ey rO iled . The decrease in lhcconvcnLi ona l a nd no till age plots was on ly 45 0 '0 (Figure 9 ri ght). Thl' live mulch ckpletcd weed seeds in a manner simil a r to crop lan d subj ected to a long period of bush fallow."},{"index":5,"size":169,"text":"Effec t of li ve mulc h all soil fe rtilit ~ restoration was investigated on a site wit h a previous history of intensive la nd usc, After fou r yea rs of cropping, t he organi c Ctl. rbon can len t of\" soil in the live mulch plots approa ched the level in newly c1 c£la'd trop ical fOI'L \"S IS while th a l in the no-tillage a nd COJ1\\'cluiona l ti ll age sites remai ned relativel y low. This demonstrates the crfecti ve ness of tropical leg um cs in ad din g organ ic mailer to th e soi l a nd improving other soil properti es at 10\\\\1 in put levels witholl t a long peri od of bush fa llow . Howevcr, management prac tices associa tcd wit h lht: usc of these legumes as grou nd covers need to be refined in order to in crease the intensit y of la nd usc in the Land ma nagcnH:rlt systcm"}]},{"head":"Convcntional ti llage","index":13,"paragraphs":[{"index":1,"size":6,"text":"Iropics a l low weed pressure."},{"index":2,"size":131,"text":"Afte r fiv e years of co ntinu ous m al zc prod uc tion involving 10 crops of l11<l iz-e. yields in live mulch p lots th at received no nitrogcn we rt' eonsiSlt'nt ly bCller than in lht, no-tillagl and cOIH\"c nti omd tillage mai ze' grown withou ni trogen . To check the residual r nccts or li ve mu lc h a nd till age: systcms on crop growt h maizc was plantcd on the l:xpcri lll clllal sitc wit hout th e app lica tion of nitrogen rcrti lizcr R esults show th at ma ize yields in th e: live mulch ploLS wcr(' signifi cantl y higher th an those in the conve ntiona l a nd no-ti ll age p lots (Table 11 )."},{"index":3,"size":6,"text":"Nitrogen applied in previoLls yea n;"},{"index":4,"size":132,"text":"(kg/ha)   New clea ri ng practices with the shear blade and subscquclll soiima nagc tn c1ll pra cti ces (such as no-ti ll p lan ting) mi nimize soil erosion and help retain va luable top soil. Eve n wit h th ese new prac tices, severa l )It:a rs of cropping can l\"eSLJ I Lin soil co mpac ti on. 'l'his is caused by IracLO rs a nd olher equipment lIsed fo r pJanling, spraying, and harvesting ope r~llion s . i\\ lulching with pla lll res idue he lps to minimize soil co mpaction , runoff: a nd erosion , but, because of CtT la in mulch manage ment problems, il has not been possib le to extend lhl' benl'fit of\" mulching [Q the large r mec ha nized operations."},{"index":5,"size":176,"text":"In silu mulch produced from the residu e o ra cover crop wh ich occu pi ed Lhe land d uring fallow has been fo und mos t suitable for no-till maize and g rain legum e production , but not a ll cover cro ps prodUCt\" residu e or mul c h co mpauble with mec ha nized no-ull p lanting. Orthose tesled aL llTA. mucuna ( l\\1IlClIfJa Illilis syn . Sli{%oilllll deeriflgial/llm ) , a k g uJ11inolis cove r cro p, has been found to be th e most co mpatjblc wit h ex istin g no-till pla nt in g equipmenl. I t is a f:] st g rowin g creeping leg uminous vin e th at fi xes a tm ospheri c nitrogen in th e soil. an d its resid ue mulch co ntri bu les 10 soi I moisture re ten Lion, lower soil tempera t u IT. an d a bui lei-up of orga ni c mat H:r , all of which stimulate 3Clivity of ca nh worms."},{"index":6,"size":86,"text":"Thc usc of mu cuna as a so urce for ill silll mulch has been reslricted tosmall-scalc manual o perat ions bcca usl' th e seed s may beco me weeds during croppin g in th e fo ll owing nliny st:a so n. In small-scal e operations, th e fa irly large seeds arc hand harvcs tcd. but th is is not fea sible fo r la rge-sca le ha rvest in g a:; machines are Il o t ava ilable [or thi s purpose."},{"index":7,"size":92,"text":"However. recent tria ls at TITA show th al killing th e mucun a pla nt and the seeds before seed ma turit y with machines is an cHccti ve mcth od to prL'vcnt the st:cd s Ii•o m becomi ng weeds in th t, succeeding cro p. or lht:: sen\"J\"al Lypes o r mowi ng mac hi nes testcd at U TA , Lh e A legum.illous cove'\" crop of m .uc ltlla (left ) has been found to be the m ost co mpatible w ith existing no-t.ill plan.t;llg equipntellt."},{"index":8,"size":62,"text":"nail mower ~dw a)'s g a \\'{o thl' IllOs t s~lli sfa clO r y resu lLs. ~Iu c una was pla nt l'd at the beginning of th e rains in ~l ay and Oa il mowed during the dry season in December . The th ic k. even cover prm'id ed a good mulch for nO-lill pla nted ma ize."},{"index":9,"size":106,"text":"Exten d ing this ill silu tec hniq ue to mec hani zed grain production in th e tropics should ht:ip t:i imina rl' ra pid so il d eteri ora ti on a nd minimize yield-redu ci ng soil compaction. It permits a mor(:' stabl e produ ction sys tcm fo r bot h small a nd la rge-scale rarm crs.  Funlwrmore, being able lO produ ce \\'iab ll' sti ckers o n fou r-mont h-o ld p la nts is a major imp rove mcl1l , a nd thl' o lckr t('c hniqllc was nOI reco mmend ed for planLS under six mont hs."},{"index":10,"size":34,"text":"i\\ tounding so il around the basc of lhl' planta not her mel hod suggestcd for stimulation of sucke rs -had 110 significant effeci w ht n co mbined with either ofllll' lec hniques."},{"index":11,"size":129,"text":"The new Lechniqu e is und ergoi ng further ( • \\'~tlu a t i o n in all -fa rm tri a ls.   Grain legume Improvement Program C ow peas a nd soybea ns, prima ril y g rown in di rrerent ecologies\\ comp lemc nt each o the r as grain legume crops. Cowp eas arc traditiona ll y culLi va l ccl in di ve rse eco logies in associcuion with mi ll et, sorg hum , maize, ri ce, cassava. yams, a nd co n oll w hile so ybea ns a rc best suit ed as a n a lLc rnatc crop to ma ize bu t a lso grown as a mi xed crop with cerea ls a nd o ther cro ps."}]},{"head":"Pseudo,lem","index":14,"paragraphs":[{"index":1,"size":135,"text":"Produc ti o n constraints for these two grain leg um e cro ps va ry a nd a rc defini tel y loca lion spec ific. The overall strategy of t he progral11. is nO t o nl y to cont inue to dcvelop thcse lin es but a lso LO aggressivel y test th e im p ro\\\"Cd lin es (genot ypes) in \\'a ri o us ecologies a nd cropp ing sysle ms. Those found suitable can be used d irectl y b y nat io na l prog ra ms in ce!\"la in arC<1S for c ulti va ti o n w hil e o ther lin es ca n serve as a n impo rta nt so urce of impro\\Td gcrm p lasm fo r nationa l breeding progra ms."},{"index":2,"size":77,"text":"To a c hi ('\\\"(' th is a nd ot her objectiv(,s, sta ll' bOLh a t headqwHte rs in I badan, Nige ri a and loca ti o ns in o ther co un tri es int erac t close ly with na ti o na l sc ie ntists. Som(' of dw key \" o u tl\"l\";)c h l l loca lio ns and the ir princ ipa l r esea rc h thrusts are:"},{"index":3,"size":21,"text":"• Burkina Fasa -Cow peas resista nt to Shiga (a noxious parasitic w{'cd ) a nd to d ro ug ht."},{"index":4,"size":26,"text":"• Niger -Du a l purpose cowpeas for g ra in a nd fackler widl minimum input s fo r the Sa hel n •glo n."},{"index":5,"size":60,"text":"• Z im babwe \" P ro misc uous\" so ybeans w hi c h can yie ld \\\\f ell \\\\'ithout inocula tion and secds w ith superi o r longl'\\•j t y ror sma II far m ers; cowpeas w i th resisL a nce LO d roug ht ror sou Lh ern Arri ca n CO Ull tries."},{"index":6,"size":42,"text":"• K e n ya -Co \"'peas a nd so ybl'a ns for mid-a lti tude a nd co ld LO lcrance: abo dua l purpose cow peas w he re leaves a re consum ed a s a \\\"Cge tab le."}]},{"head":"• Phil ippin es","index":15,"paragraphs":[{"index":1,"size":26,"text":"Cowpcas a nd so ybea n li nes suit ab le ro r r ice-bascd cropping s ys t e lll~ in so uth east Asia."},{"index":2,"size":20,"text":"• Braz il -Resista nce lO pOlyvirus in cowpeas and improved soybea n gcrmplas m fo r La tin America."},{"index":3,"size":152,"text":"Scientists have started to stratify IITA -mate rial for specific ,•egions and to incorporate loca l adaptabiLity in new lin es for nationa l breeding progra ms. Also, plans arC' being made to introduce regional coordinated tri als. Ln th e pas t, a large number of advanced nurseries have been seL up as international trials throug ho ut the world . In most cases, these tria ls were not location specific, but und er the new proposed system , lITA should more effecti vciy serve th e national programs and assist th em in d eveloping improved lin es in a much shorter period. tronger regional breeding progra ms sho uld a lso help solve sOllle orth e regiona l constraints. Funhermorc, varie ti es developed und er this system have the po tential to be stabl e ror a longer period , thereby redu cing lo ng-term resea rch COSts."},{"index":4,"size":55,"text":"Resea rch has been started on the develo pment or dua l purpose cowpeas ror bo th grain a nd rodder suitable ror th e Sahel with minjmum inputs. There is a criti ca l sho rtage orrodd er ro r a nima l reed in most semi-a rid Sa helian countri es in Arrica."},{"index":5,"size":213,"text":"An addilional gra.in legume program dimension was add ed during 1985 to our soybean research -soybean utiliza tion and processing ror ho me consumptio n. Although in its infancy, this project is proving to be of mu ch interes t to na tiona l authorities, nutritionisls, and rural women.  Drought Tolerant Cowpea Varieties for West Africa D rought -a serious problem in the semi-arid regions of West Africacan o ccur at any tirne during a crop season, but the damage to c owpeas is more pronounced when it coincides either with flowe ring or pod filling. Very few known varieties can produce reasonable yields under low and erratic rainfall, h igh soil and atmospheric temperatures, and sand winds, partic u larl y in the Sahel areas. Also, some of the varieties that do survive under thes e conditions lac k certain othe r desirable traits such as good seed quality and resistance to diseases.   Thesc I1('W \\'arict il..' s wiLh preferred sted c ha r actcrs a rc also capHble of producing enough p lant growt h 10 ma ke the m usefu l fo r forage. A li mited q uan ti ty of sced is a va ila bk fro m the I ITA /SA FG R A D Proj ecl."}]},{"head":"A cow p ea C\"op seve\"e ly dam.age d bJI droug ht in BU\" k ina Fa s o.","index":16,"paragraphs":[{"index":1,"size":176,"text":"Root Systems of Cowpeas and Their Relationship to Drought Tolerance D uring th e p ast two year s, scientis t s h ave exa m in ed the gen e ti c va r ia bi.lity fo r root c haracteristic s in co'vpeas, a nd the ir pre limina r y r esults s h o w s i g n i fi can t diffe r e n ces a m o n g seve r a l UTA-impro ved varieties for roo len gth a nd Ulass w ithin four w eek s after pla nting . In t h e semi-arid r egio n s of t h e t r o pics w h e r e fa rme r s normally plant t h e crop , fas t g r owing, d eep , a nd d en se r oo system s a r e d esirable b ecause t h ey can inc r ease r esistan c e to dro u g h t ."},{"index":2,"size":127,"text":"I n cowpea produ ctio n a rras, ra in ra ll m a y exceed crop-waleI' usc durin g pan of the ra in y season. Sin cc mos t of th e waler in th (' sUlface laye r is los t by (' \\'apOl l'a nspi ra li on : pa rt of the excess WHlcr is on ly avai lab le d ee p d ow n in th e so il pl'O file. H ere il is access ible onl y to va r iclies with d ecp , eX lcnsiv(' rOO l sys tc ms. Also , bc tt c Tab le 14. R oot c ha rac te r istics of llTAimproved cow p ea v Cl r ieties ."},{"index":3,"size":162,"text":"roOt growth can be pa rticul a rl y useful in soils tha t offer co n s i d~r a blc r ~s i s t a n ce t o roOl deve lopment. A \" Dior\" soil in the se mi-a rid zone ofSl'nega i is a n example. Trials a lllTA show('d th at va ri clies IT 82 E-60, IT 8 ID-I020, and IT 82 D-8 12 had ra Sler roo t growlh and IT 82E-60. T V, 3236, an d IT S ID-716 rela ti ve ly more roo t mass co mpa red with oth er va ri eties (Table 14). Variety rri a ls in Sa hcli a n cll\\'ironm cnts have shO\\vn TVx 3236 a nd VITA-3 to be dro ught tol era ill . Further studies a rc un derway to cla ri fy the rel a ti onship bet wee n roOl c harac teristi cs and drou ght to lera nce."},{"index":4,"size":133,"text":"Left , a cowp ea v ariety (I T81D-1020) w ith afast \"ootgrowtlt a nd \";g ltt, one w ith ??lore root mass (VITA-S) w hic h is d\"ought tole rant i\" Sa he /ian e nvironnle nts. Esse ntiall y) a good d ua l purpose va riet y shou ld produce a reasona bl y fair grain yield (600 to 800 kg/ha) whil e retaining its foliage UI1lil th (' end of the season when the vin es a nd leaves arc harvested for foclcl er) sun-dried . and stacked awa y for livestOc k feed in the dry months \\\", hen pasture is 110l avai la ble. BOl h gra in a nd fodd er a lLract almos t eq ual ma rk et prices in urnes or sca rcity."},{"index":5,"size":140,"text":"Loc,,) I long-maturing va ri e ti es ( 100~1 40 da ys) produce good rodd er b ut very low grain yields ( 100-200 kg/ ha ), a nd severa l new va rieti es ave rage 1.500 kg/ ha of gra in in 55 to 75 da ys but ca nnOt be used for fodd er because th ey shed their leaves a t malUrity. In-be tween th ese \\v.'O groups a re varieti es which, if properl y managed , can serve th e dual purpose usage. To meel this req ujrcmcl1t, UTA and nauona l program scientists in Ka no. N igeri a and Ni a mey, N ige r Republic eva lu a ted so me medium ma turing cowpcas rol' lheir suitab il ity as gra in a nd fod d er varieti es."},{"index":6,"size":80,"text":"Preliminary n.:s ults from Kana in 1983 ind icated th at TYx 4659-03Ea Illultiple disease r(.'sistam va ri elY -co uld be suitable as a dua l purpose cow pea. I r gave hig her gra in ( 1. 7 l/ha) a nd focleler (4.5 l/ha) yields lha n either I A R 34 1 ( 1.6 llha or grain and 3.5 ll ha 01' rocleler) or IT 82E-60 (1.1 ll ha or grain a nd 0.8 llha or lodder)."},{"index":7,"size":188,"text":"A m u ltiloca lion tria l involvi ng loca l an d im p roved va ri eti es ca rried o ut at resea rch stat ions a nd ra rm lTs' ri eld s in K a na an d N ia m ey a reas in 1984• co nfirm ed lhe su perio r q ua liti es o f TVx 4659-03 E as a dua l pu rpose cow p ea. Yic-l cis oblain l'd for th is \"a ril\" IY in N ign ia ra nged fi'om 1.3  In th e 1985 croppi ng seaso n , ot her \"a ric-Lics w hi c h co mbi ne hi g h g rain yield wi th pes t a nd d isease res ista nce a nd good consum er a ppea l R esea rc h is co n ti nuin g La id enti fy d u a purpose li nes tha t will perroJ\"m we ll w he il11 erc roppcci with cerea ls a nciundcr m ini mum pro tcClion inpu ts.   •• Not inc/mild ill al1alysis/or gmill),irld."}]},{"head":"Co w p ea f odde r f o r livestock put 0 \" t op of ho us e s t o dry in a v illage ne ar","index":17,"paragraphs":[{"index":1,"size":51,"text":"Table 15. Pe rformance of dual purpose c ow pea line s at Santttru, Nigeria and Nialney. Niger R epublic (1985) . bo th isolates Crable 16). The breeding lin e IT 82E-16 was rcs islaT1t lO the \"Onne\" isolate bu t susceptible to th e \" TT-1 6\" iso late."},{"index":2,"size":77,"text":"The scrt.xning-o r 59 cowpea linl's 10 the nt'w isolate orCY;\\ IV ( \" K \" ) IT\\'('a ledth a t Vit a-I. Vita-3, and IT 82£-1 6 a rc a lso hig hl y resis tan t to th l' new iso la te (Table 17), Cowpea lincs IT 82E-10 and T \\ •u 4•10. w hic h a rc immune 10 th e standard isol(l tf' C'{:\\lV-6. showed a susct'Plibk ITaction 10 Ihe CY:\\lV-K strain. "},{"index":3,"size":248,"text":"., = flO J..J'II1PloIIIS. 5= U/'rrt S)'mptoms. Results obta ined in this s tud y d emOn stnllc that some breedi ng lin es ro und ea rli er Bu t cow pea produ ction has so me constraillls to overcome, incl udi ng yield losses caused by the cowpea severe mosaic virus (CSrvl V) an d the pOlyvirlls comp lex. The former is specifi c to th e Ameri cas a nd strai ns of the latter a ppear to be di fferen t from cowpea ap hid•bo rn e virus ( CA b~I V ) in A rrica . T o help reduce the yield losses caused by tlu:sc viruscs, Brazilian and II T A scientists arc inco rporating res isUlncc illl imp roved gcrmplas m .   Braz il, ( 1985).      Find ings of' this research sugges t that soy bea ns ca ll cOl11 lx'nsa lc for a lowe r pop u-I:Hion a nd fi ll in ga ps resulting rt'o m poor stand estab lishment with more vigorolls g rowt h. But th e resea rch a lso indica tes t hat the la rme r ca n achieve grea ter yit:ld by p lan tin g in closer rows. T he dikl11m:l and c hallenge ror fu nher resea rch ma y be LO find how th e f;:lrlll cr Ca n cha nge th e paut.:rn of' rigid ly fix ed wide ridges using ava ilable IDo ls and me thod s."}]},{"head":"Two c o w p e a b,-eeding l in es '-es istcwt t o aphids (left. (HId right) co mpm-ed w ith a s us ceptible liue in t he middle. Table 20. Yie ld p e rformance of aphid resis tant cowpea va rieties atfive locatio ns (1985) .","index":18,"paragraphs":[]},{"head":"Relationship between Populations and Row Spacing to","index":19,"paragraphs":[{"index":1,"size":145,"text":"..  Realizing th e potc ntia l prob lem of SMV, sc ien ti sts crossed tropicall y ad ap ted li nes with soy bea n inlroduct io ns from th e U.S. kn own to be res is talll to this virus. Segrega tin g F3 populatio ns from th ese crosses were g rown a t IITA headqu a rt ers in the 1983-84 dry seaso n wit h a suscep tib le contro l va ri ety; eac h plant in th e popula ti o n was inoculated with S MV iso late \" Ivlicro-A\" -a hig hl y vi rulent strai n of th c virlls whi c h ca uses seve re sym pto ms. Plants showi ng S~I V symplOllls were pu ll ed a nd th e rema ining p lanls harvested indi vidua ll y."},{"index":2,"size":198,"text":"A rew seeds from eac h plan t were tcs ttd fo r res istan ce to s~lr v a nd the n:ll1aining st:ecl show n in p roge ny rows in th e 198+rain yseason. Abo ul ha ir o r the p lants that showed no symptoms ann in ocul ati on in the fi e ld th e previo us dr y sea so n had sympLO l11s aft e r in oc ul at io n w ith th e sa me iso la te in th e g reenhouse. Si ngle pla nts wert.' selec ted in th e fie ld in 1984 frol11 progt:n y rows or lh e lines tha t showcd no rea ction in the green house. Th esc plants we re g row n in progen y rows in thc 1984-8.5 d ry seaso n w ht.\"rc th ey we re t('sted fo r free nodul ati on , seed sto rabili ty, a nd shatterin g. T he plants accep tab le fo r th ese tra its wc re harvested and used in a yield trial a t M_ okwa , N ige ria in 1985."},{"index":3,"size":142,"text":"A t l he most rccCIll stage of tes tin g, seed from eac h entr y in th e field tria l was aga in sow n in th e g reen hOllse a nd tes ted with SMV-\"M icro A\" a nd wilh anot her isolat. Areas culti vated with maize in the North ern Gu in ea Savan na zone (900-1200 mm rainfa ll) have increased dramaticall y in the pas t two d ecad es. But as the maize spread so did Shigaa parasitic weed. A 1984-85 survey co mpleted in Nigeria , Benin , and Togo showed tha t under severe infes ta tion farm ers abandon their fi elds because of complete crop failure. Even in well ma naged , highl y fertilized experimental ficIds yield reduction of susceptible varieties was as high as 90% ."},{"index":4,"size":88,"text":"The maize progra m initiated screening work for Shiga resistance three years ago under na tura l field infestation, and several inbred lin es and hybrids were developed showing to lera nce and reduced damage under SI1'iga infesta tion. U nfortunatcl y, because natural ficld infesta tion is no t uniform and some times unpredic table, it docs not permit effi cient breeding programs. Therefore, a ttempts a re presentl y underway to develop more reliable screen ing methodology in the fi eld , greenhouse and la boratory."},{"index":5,"size":56,"text":"vVork has continued to screen for resistance to stem borers, particularly Scsamia calamislis which is one of five different species causing significant yield losses in Africa. Progress so far is only margi nal. Therefore, we arc intensifying effon s to develop artificial mass rca ring facilities for mai ze borers and reliable field infestation techniqu es."},{"index":6,"size":41,"text":"Al thoug h sta lk rot usually docs not reach epidemic propo nions, it causes from 10 to 15 % yield losses in fa rmers' fields du e to prema ture dea th of the maize plants and or lod ging."}]},{"head":"Artificial fi cld infes ta tion techniques have been adapted to the tro pica l environment at","index":20,"paragraphs":[{"index":1,"size":18,"text":"Ibadan for three causal organisms, and they are being used to screen for resistance to sta lk rot."},{"index":2,"size":33,"text":"The techniques a re relia ble and uniform and bein g widel y used by maize breeders in population improve ments , as wel l as in inbred lin cs and hybrid developmcnt."},{"index":3,"size":162,"text":"SLOrage insects a lso acCount for a share of th e losses sufTcrcd by fanners. But our scientist be li eve th ey ca n develop maize vari cti es in th e future w hi ch will be resistan t or tolerant to weevils. Observa tions during 1985 showed grea t va ri ability among ma ize varieti es and hybrids in response to long-term sLOragc und er norm a l 1'00111 tempera ture cond itio ns. Some people beli eve tha t hybrid s have a narrower ada pta ti ona l range and that thei potcntia l ca n be rea li zed onl y und er good growin g conditions and management. Result obtai ned for two of the hyb rids docs not support this bel ief: These hybrids we re found t perform we ll across different ecologica l zoncs in N igeria and a lso under strcss conditions sllc as droug ht and Slriga inrCS tCllion."}]},{"head":"Research in the hybrid","index":21,"paragraphs":[{"index":1,"size":122,"text":"In thefollowing pages, afew 1985 research highlights are briefly described. More complete information on these topics and those mentioned in this Executive Smnmary can be obtained by requesting the Annual Report of the Maize Research Program. Development of Extra-Early Maize Varieties I n \"bad years\" when the rains start too late or cease too SOOD , extra-early maturing maize varieties can play an important role in the Sudan Sa vanna of setn..i-arid West Africa. Farmers can minimize the risk of crop failures by planting varieties that reach 50% silking within 42 or 43 days. Ifafarmer is not able to plant until July 20 because of w e ather and/or soil conditions, extra-early maturing varieties couId make it but not later maturing ones."},{"index":2,"size":83,"text":"Limited rainra ll a nd t he low water-ho lding capacit y or th,' prcclom inal1l soils impose limi tations be tween th e cm\"clivc' Icnglil or the growing seaso n and thl' variety cyell' (FiguJ\"{ 12). Tn topostq utnce trials a t K ambo inst' Burkina Fasa in 1984 -a \" bad year\" -ea rlin es was the key ra CIor determining maize grai n yield. On ly 227.4 mm of ra in 1~1I betwe<•n plallling time a nd h'1rVl' S L."},{"index":3,"size":218,"text":"The earli l'S t maturing and best yielding varieties were Raytiri local and Ko ud ollgol loca l a mong six varict ies tested . Their mean yields ac ross five positions a long thl' 10 p O sequence ra ngin g rrom la p to bO ll o m Wl'I\"<' 365 kg/ ha and 340 kg/ha , respec tively, as co mpared wit h I 19 kg /ha ro r SA FlTA-2 and 165 kg /ha fo Kamboinsc loca l -both later maturing vari eties. Man y or til(' ex perimental plots a nd til(  How('vcr) in averagl' or bell('r ra infall years l'a rl y or medium ma turing varieties producl' hi gher yidds than th e eX lra-ca rl y. Even so, th c lattt'!' a rc slill acce ptable in \"good years\" a nd with breeding ca n bl' furth er improved. In 1985 tri a ls in Burkina Faso. three va ri eti es -Bursanga T a llo, (C ue 3 14x Mex 497) F. p and CJ P which silkcd in 42-43 d ays had mea n gra in yidds across th l'lT loca ti ons (Ka mboinsl'. Ga mpcla, a nd Sa ri a ) ra nging from 2,+44 to 2,985 kg/ ha. Comparable mea n yields fo r n ll'i-"},{"index":4,"size":24,"text":"In the \" bad\" rainfall year of 1984, the best yie lding extra-early local maize variety ill trials at Kmuboinse, Burkina Faso was Raytiri."}]},{"head":"74","index":22,"paragraphs":[{"index":1,"size":65,"text":"Nics which silkcd in 50 10 54 d ays ra nged fro m 3.641 LO 4.1 26 kg/ha. BUI beca use no one can acc uratel y predict a Hgood \" or \" bad \" rai nfa ll season, plan ting ex tra-ea rl y maize a long with Ot her va ri eties improvl's lhe fa rmer's cha nces of harves tin g something."},{"index":2,"size":135,"text":"Man y people in lhe udan Savanna of s(' miarid \\'Ves t Afri ca COLInt on ma ize to fill th e food ga p during the \" hu nger period \" belwee n th e tailc nd of food stocks or th e previous season a nd the ha rves t of th (' la tc loca l sorghums and mill ets. This food gap sets in carli n following a \"bad yea r\" whi ch emphasizes the need ro grow v(, ry ea rl y calch crops such as extra-earl y maize whi ch ca n be harves tcd and eaten before maturit y. A va ri ety of 70 d ays to ma turiL Y ca n be harvestcd and ea ten as green maize off-the-cob 60 d ays aft er planting."},{"index":3,"size":206,"text":"Scientists arc calk-cLing and selecting additiona l ge rmplas lll from d iffercnt parts of th e wo rld to improve prese ntl y ava ilable ma tcri a l. In th e severe drought yea r or 1983, it was tested aga ins t the IWO best yieldi ng open •po llin ated va ri eti es (T Z B a nd Poza Ri ca 78<\\•3) across six loca Li ons in Nigeria (one rOreS L a nd fi ve sava nna ). The hyb rid yid d ed a n a Vl' r:'lgeorS L/ ha co mpa red with 5.5 and 5.1 t/ ha rol' the two opc' n-polli na ted \\'a ri l,ti cs, Simila r wid e ad a pia li on a nd yi eld sta bi lit y or thi s hy brid we re obse rved aga in in the 1984 an d 1985 crop pin g s('asons in N igeria and so me other \\V CSt Arrican countrics. For cxarn ple. in three out of fou r tes t locations in Cameroon hybrid 8322-13 sign ifi ca ntl y ou tyicldcd (b 39,0,,0) the lOp yieldin g c hec k va ri cty Poza Ri c 7822-SR ."}]},{"head":"Selected upland ma r:ze varieties d eve loped","index":23,"paragraphs":[{"index":1,"size":108,"text":"Sta bi lil yorlhe hyb rid 8322-1 3 was also tesL ed und er two di n-e re-Ill stress condi ti ons -strea     SevtTal ma ize vari{•li<.'s showed low kvC'ls of w(\"c\\\"il d a mage \"fu.' 1\" fi\\' c month!) in storage (Table 251. t\\ yellow nim-dem hybrid (8329-15) sufftTi.\"d less than lO r) (J kernel damage co mparcd wit h 70 0 () for a locall y grown va riet y (\\VcsllTn Y rllow). Among ll1{' whi Ie rna izC' hybrids. 8321-18 ra nk ed th e:: b (,S I with k ss th an 20°0 damage co mpar('d wi th Bon n fo r 8338-1 ."},{"index":2,"size":110,"text":"A llhough s(\"cd \\'iabilit y fo r a ll materi a ls tl\"s t('d differed lillk afte r thrc(' months of storagel significa nt differences were observed a flcr fotlrmonths. SCl'd viabiiit y remaineci hig h (o\\'cr   were identified as superior germplasm, t hey lacked resistance to maize streak virus disease. Therefore, to increase the scope of their adaptation and adoption by African farmers and increase the diversity of maize germplasm available to them,join efforts between the two internation a l research centers was initiated five years ago to introduce streak resistance into t h ese varieties. (The seriousness of this disease in Africa is described in the Executive SUlDmary)."},{"index":3,"size":181,"text":"Fourt een ma ize va ri eti es a nd populations (mostl y from C I1 Vl?1.1YT) we re selected fo r a conversion program for sln.:ak resistancc' using t he backcross proccdurt' Cr ab le 26) . These va rieties reprl'scn tecl dif1t'!\"c n tmaturit y grou ps, grai n types and color, pro tein qualit y cha ... :ICtnist ics, and ecological ad apta li on. Streak resistance popu lations developed a t I ITA ,vere used as the so urce or IT'sisL ance a nd th(\" selected va ril..' tics as n:curn' :1ll pare nts. During th e course of co nvers ion, a rtifi cial in festatio n with kafhoppers carrying maize streak virus was per-rorm ed a t ('vcry stage of th e procedure to ens ure th e trans mi ss ion or resista nt genes to th e rc CUIT('1ll parcnts. Eleven va ri eti es a t th e end o 1985 had reached th(• BC\" or Be;, stages con sicil'l\"cd as ad equatc rccovrry of the prcfer red varietics' ge not ypes."},{"index":4,"size":95,"text":"The mOl\"(' ad vanced convr n ed varie ti es were in cluded in the streak resistant variety trial d istributL'd by I ITA in Africa with enco uraging resu lts; 28 entries including strea k res ista nce donors, recurrent parents, and B~ a nd BC~ ge nna lions were tl'sted in four locat ions in Left, a ,naize v ariety susceptible to streak disease used as a recurrent parent in a backc ross w ith a res istallt dono r to pl'oduce the resis tallt va r iety a ll the right ."},{"index":5,"size":32,"text":":\"J igc ria . At I IT A the tri a l was co ndu ctr-d u nckr a rti ficia l infestat io n LO induce strea k epid emi cs."},{"index":6,"size":134,"text":"Strea k resista nce le vels of BG, ! a nd BC .• ge nera tio ns Cr ab le 27) W CT C simila r LO th e dono r popula tio ns, indica ting th a t the bac kcross method was a n efficient proced ure for transmitting stn:a k resista nce gt.' n cs. nder no n-strea k co nditio ns, both BG l a nd BC 4 genera ti o ns had similar yields as th eir recurrent pa rents. I n ma ny cast's, however, BC 4 gentTa ti o ns shownl hi g her yie ld a nd be llCf\" unifo n n it y in pla nt a nd ca r cha rac tcristics th a n th e BG l gcnc ra ti o ns."},{"index":7,"size":199,"text":"The cO ll vtTtcd va rini cs a rc now avail a ble to na tion a l progra ms in Afri ca a nd represen t a sig nifi ca nt co nt ribu rio n to ('(fo rts LO minimi ze yield losses du e 10 ma ize sirea k virus in Afr ica.    El even inbred lin es, d evc lop ed < 1l IITA a nd pl a nted in th (' 1985 sccond seaso n, were inoculat ed with spore susp ensio n of the thrl't' p a thogens, se para tel y, an d wi th a m ixlUre or three. The sta lks wer e split lo ng itudina ll y for rot inleslalion cva lu a tion four weeks after inocul atio n. Disea se rea cti o n was eva lu a ted on th e basis o f\"th e ra tc o frol spread from th e point of inocul a tion using a 1-6 scale ( I = less th a n o n (,-fo urth of the inocu la ted internode roW•n and 6 ro t spread ing to twO o r ma n: intern odes) ."},{"index":8,"size":117,"text":"The inbred lines showed a ra nge o f reaction against th e pathogens (Table 28) .    uproot the ma iz(' pla nt to o bslTVC S/riga a tt ach-!nCIll, and time is saved beca use the roo ts do not need to be was hed. A lso, th e na tun' o r th e medium resulted in ea rli er emerge nce of the parasit e. By using both Pet ri dislws in the labo ratory a ndjiff~' pots in the green housc! rour inb red lines a nd two hybrids with known react io n LO S/riga und er natura l fidd co nclitions wc re tl's tcd for st imulant produc ti on."},{"index":9,"size":33,"text":"Sig nifl ca nt dilkn.:nc('s in gc n n inatio n of\" Slriga seeds were obser vcd. Thl' differences 'H e we lI corrcJat('d with th e field observati on (Table 29) ."},{"index":10,"size":141,"text":"Earl y sympto ms orS/riga infection in the field indicat(' the possible action of toxins in th e disease etiology. A techn iq uc usi ng cruci c Slrigfl extract injec ted in to mai ze plants three \\wcks a ll er planting resulted in var ieta l differences betwecil susceptible and tok-ra11l hoSl varictics. This me thodo logy a ft cr refinl'ment appears p romising for app li cation in large sca ll' fi d d sc reen ing a t II TA w her(' th e organism is abse nt. I t will a lso per mit tes ting gC l'lnplasm 1' 01' toleranc(' 10 ot her Slriga species of economic impo r-(ance. Thro ug h these processes only d esirab le ma tcrials wi ll be scree ned under field conditions a t vario us testi ng sitcs."},{"index":11,"size":250,"text":"Field scrc('ning undcr hCa\\'y Slriga pn:ss ul\"(' is Ill{' final ('va lu a ti on stage. Since 1985. thi s was co ndu c ted under natura l infcsta ti o n whi c h unfortunatel y is not uniform. A m e l hod of artificial inoc ul a tion in th e field was tri ed with litll t\"' success. The lcchnique wi ll be mod ifi ed in 1986 to aim at predictable a nd uniform levels of Shiga infes tati on in the fif• leI .   More than half of tlte rice in Africa is grown under uplan.d conditions . a nd. in hig h ra infa ll arcas w here dro ug lll su•css is o f minor con cern. ri ce produCLi on could be in creased s ubsta nti a ll y. 1 rTA 's r iel\" brel\"d ing wo rk a t O nn c in sout heas t ~i gl' rj a is d eveloping superi o r upla nd va ri e ti es to lerant to soil ac idit y a nd discases a ssocia ted with a hig h ra infa ll. humid forest ecology. ~ll os t successful li nes in this eco logy combin e to lerance d eri ved from tradi t io na l Afi•ican upla nd pare nts wit h the sho rt ('!' straw and hi g her ti ll crin c ca pa ci ty of mocl el\"n sem i-c1wa rfs."},{"index":12,"size":196,"text":"Fo rth e third consecuti ve yeal\", the v;'lri e l Y ITA 307 yielded 60°0 111 0n: tha n the loca l c heek OS 6 w hen reaso nable improved cultura l prac ti ces were ad o pted . Varicti es lik e ITA I 16 ITA I 17, ITA I 18, a nd ITA 307 w ill have a m ajo r impac t if used w ith good ma nage m ent in the coa sta l ri ce bL:it in countri es suc h as G uin ea, Liberia , S ierra Leone, and T vory Coas w here ri ce is the di ctar y stap le a nd up landl.. -'cologics predomina te. Such va ri e ti es a rc fiTl from lhe loca l stress of g ra in discolo rati o n a nd blast. 1n coopera ti o n with the na tiona progra m o f Li beri a . tests a rc being ca rri ed o ut with se\\'('ra ll£1 l(, ma wring selecti ons for lhe hi g h ra in fa ll , upla nd conditio ns ther e."},{"index":13,"size":130,"text":"U nd er 10vvl' r ra inndl conditions (less than 1500 mm /yea r ) , earl y-maturing li nes with dro ug ht a nd blast resistan ce have s hown pro mise . ITA 257 and ITA 235 !HI Vl' droug h tokra nce, a nd the fo rmer va ri e l y possesses du ra bk resista nce for blasl. Beca usc suc h a r('l:Is arc p rone LO dro ug ht, th e e mphasis is o n breeding a n ea rl y va ri (' ty 10 01 int o the sha n g rowin{ season wi til rcsisl:-l nce to dro ug h t. Iraf a nd n('c k b last. a ncl g ra i n cI iscolora lio n."},{"index":14,"size":237,"text":"The raillJed lo w land (hydrornm\"phic) ecology also offe,\"s a great potential fo increased ri ce p rodu c lio n in Afri ca beca use lhe rice pla nt has a dequ a tc mo isture in Ihe roo zo ne lo r a t lea sl a majo r po rtio n of Ih l' g row ing cycle. Also , va St a reas of such lands a re ava ila ble fo r ri ce c u lliva Li o n (abou t 20 millio n hecta res) . How{'ver 1 varie ti es \\o \" ith l o lcra n c ~ LO a constan tl y fiu c LU 3 ting wa ter rC'gimC' a rc required . A new breeding prog ra m has bee n in iti a ted to d cvtlop supe ri o r and hi g h yie lding lin es for suc h an ecology. Scient ists a re wo rking o n the d evelo pment of ri ce lin es with ea rl y \\•igo r to withstand seedLin g clro ug lll interm ediate stature to compete with weed s. ada pta bilit y to g row und er stag na nt and so mcti m es iro n-tox ic wa tc!\". a nd to kra nce to a c ha ng ing k \\'e l oCnu tri ent !-i uppl y."},{"index":15,"size":103,"text":"Lin es such as ITA 306 a rc well adapted for suc h eco logies, a nd , if grown und er op tima l man age ment, can yield a s muc h as 4 t/ha. A lso, a sccond c rop suc h a s 60-d ay cowpcas or vege tab les ca n be grown afte r ri ce on th e residual soilmo islurc. This in creases th e intcnsit y o f la nd a nd vva ter usc effi c ienc), and red uces th e weed pro bl em for the succeeding rice c ro p."},{"index":16,"size":192,"text":"A nother rice growing ecology that receives )\"esearch attentionin land va ll ey swamps is c ha rac tcri zed b y p a tc hy areas of iron tox icity w here susceptible va ri e ti es fa illo d o well. IT'A 249 -one of iron to le rant va ri eties -has perform cd be tter than the traditio nal LOle ra nl varie lY (Suakoko 8) in Liber ia w here iron -LOxi c so ils lim it ri ce produClio n. As a rurther step in varie ta l improvement. ror this eco logy , ri ce lin es wi th a wid e ra nge o r g rowt h d ura tion a nd be lter level or resistan ce to neck b las t have been genera tcd a lUTA. l 'hesc are being ('va lua lcd in iro n-toxic soils a t S ua koko in co lla bora Lion with the Centra I Agrjcu ltura l Resea rch I nsti lLl te, (CA R 1) a nd the W es t Africa Ri ce Developmen t Associa ti o n (WARDA)."},{"index":17,"size":190,"text":"Unquestionab ly) rice yields are highest w here assured irrigation is possible and severa l eli te va ri c ties arc a va il a ble for irrigiHed conditions where th ere a rc no Africa-specific stresses suc h as Lhe ri ce yellow mOllie virus disease ( R Y iVIV ) . During th e past yea r. fi e lcltcs ts have show n th e superi ority of ITA 2 12, ITA 222, and ITA 306 in a number ofsLress-li'ec loca tions in Ca meroon , N ige ri a , a nd G ha na. Prelimin a r y res ul ts from th e R epub li c o f C had a lso indica te tha t fTA 306 has hi g h yield pOlc nri a l thcre. These va ri e Li es have yield ed a n ave rage o r 5 t/ ha und er mod era te ma nagcmen t, and the la n er two ha ve ha d stab le yie lds during th e pasl three years in N iger ia a nd Cameroo n."},{"index":18,"size":143,"text":"Further prog ress was mad e during 1985 in id elltifying seve ra Ili nes tO lera nt tO R Y ivl V and held tested in end em ic a reas ill the R epubli c of N iger. The be tt er lines a rc being rein forced with d esira ble agrono mi c tra its to prod uce R Yl\\1V-tolcra nt , high-yielding ri ce lin es fo r seve ral countries where the disease occurs. Th e va ri e ta l improvemen t is backed li p by a sensitive sero logica l lest for id entifying the most resista nt lin e. In add itio n to drawing resistan cc fro m O. sa/iva va ri eties, plan l breed ers a rc a lso loo kin g ,:1l the Africa n ri ce . O."},{"index":19,"size":8,"text":"g/aut'ITill1 fl ) a s possible clo nors."},{"index":20,"size":90,"text":"Simi la rl y. Africa n-specific insect pes ts such as Diopsis (tho racica) 11100\"0/)/10/1110 ) ga ll midge, a nd severa l spec ies of borers a nd gra in sucking bugs a rc co nstra ints 1.0 ri ce prod u c ti o n. Spec ifi ca ll y d esigned scree ning procedures have ena bled scie ntists to id entiry resista nt lines, and they a rc using resista nt d ono rs for Dio/)sis and ga ll midge in th eir breed ing programs."},{"index":21,"size":51,"text":"Pr io rity a tll'flli o n is being g ivc n to a n intcgra ted a pproach LO pest manage m c nl ~ including no t o n ly resistant \"arielies bu t a lso che mica l, cultu ra l, a nd bio logica l contro l."},{"index":22,"size":157,"text":"For higher a Ltitudes, IITA 's breedingprog,-arn has ide ntified superio,' Lines fo r cold a nd bl as t tole ran ce a t Dschang, . \\ /fbo, and Ndop pla ins of Cameroon, sites whic h ex pose th(' tes t lin es to dilTerent regi m es or lo w Lempera ture a nd associated stresses suc h a s b la st and shea th rot d iseases . Low tcmpc-rature is a sc ri ous constraint l O rice produc ti on in the mida ltitude zones of cas t, so uth , a nd ce nLral Afi•ica n countri es a nd a lso a t higher lat irud es during the second crop season (November-Februa ry). 1 R 7167-33-2-3, testeci over th e pa sl Ihree years a t Ndop Pl a in , is being grown over large a reas beca use o f its superi or performan ce."},{"index":23,"size":323,"text":"During 1985, the rice quality laboratorJI contintted to provide the n ecessary backstopping to the bre eding program b y screening rice lines from II TA's la rge germ plasm coll ection a nd n'om seve ra l J\\fri ca n co un t ri es to g athe r info rm a ti o n o n qu a li t p rrfe re n ct:s of co nSLIm c rs. Prdi: re n ct:s lo r cookin g a nd eat ing qua liLi es often d inc\"!' from co unt r~' to country. II T A h as a \" 'id e ra nge o f\\ 'aricties to su it l he taste arq ua lit y preferen ce o ma n y Afri ca n na tions (ReJMrrh lIighlights 19B-/). During 1985: six tri a ls w ith seve ra l hund red e n t ri es we re se nl to 186 loca ti o ns in 2 cou n tri es so u t h of th e Sa ha ra, a !lei a n ex p a ncl cd p rogr<t In w i t h n ew tria Is wi II be fo rll1 celu nd e this n ctwor k d u rin g 1986. Fi ft(' c n ri ce scien ti sts fro m se ve rn I na tio na l p rogra ms wer involved in moni to ring tou rs to ke y t(,s t loca ti o ns in fOLi r \\Ves t A fri ca n CO LIn tries. T hi inte ra c tio n resulting in spec ifi c recomm c n da ti o ns he lps bo th na ti o nal a ncl II TA ri e sc ie ntis ts impruve th e ir stra tegies fo r hi g he r ri ce produ c ti o n ."},{"index":24,"size":39,"text":"In the following pages, several research highlights during the year are briefly described. More complete information on these topics and those mentioned in this Executive Summary can be obtained by requesting the Annual Report of the Rice Research Progrant."},{"index":25,"size":141,"text":"Performance of High Yielding Rice Varieties in Three Afr ican Countries A ccording to r e p o rts from Cam e roon, Ghana, and Nige ria, sel ect ed rice varieties d e ve lope d b y IITA for irrigated lowlands have s h o wn supe rio r p erfo rma n ce in exte n sive tests at e xpe rime n t s tations a nd in fa nn e r s' fields. ITA 222 and ITA 306 no t o nl y produ ced hi g h y ie lds but also s h o wed a wide range o f a dapta bility . Both varieties wer e h eavy tille ring a nd produ ced long g r a ins with acceptable physicoche mica ch aract e ri s ti c s ."},{"index":26,"size":158,"text":"O vc-r a th rce-Yl'a r period ( 1983 85 L g ra in yields of the two va ricties a t II T A avcraged mo rc than 6 t/ ha Cr able 30 ). IT A 222 m 3 IUrcd in 123 da ys a ft er plan ti ng a nd reac hed a htig ht o f abo ut a il e me Ie r . Th is va ri t. ' lY in t ri a ls co ndu cted undt'!\" th e allsp ices of th e N ati o na l Cereals Resca rc h ln stit u t(, in eig ht locatio ns in :\\,igc ria ha d a n ave rage yiel d o r 5.3 tlha (T abk 3 1). I, a lso ma tu red ea rli er a nd was less pro llc to lod g in g th a n o th er va rieties."},{"index":27,"size":108,"text":"I n Ca me roo n. I'rA 222 o ll tyicJd cd T a ina n V a widel y g ro wn \" a riel), by a pp ro xima tely    Long slender g rains, resistan ce to blast, and the ab ili ty to pe rform well und n irrigated a nd hydrol11orphic soil condit ions a re the main a llribulcs of ITA 306. Th is va ri cl Y -now undergoing la rge-scale restin g in Ca meroon fil s we ll iTllo rice-based cro pping sys tC'ms with cow peas fo ll o win g r icC '. In G hana. il     ."},{"index":28,"size":14,"text":"• Ii = resis tan t . 1\\1 R = modtmttly resis/fl l/ t."},{"index":29,"size":144,"text":"Problems and Potential for Rice Production in Hydromorphic Lands P roper use of at leas t 20 tnillion hectares ofhydrOiDorphic land presently a vailable in West Africa for r ice c ultivation co uld substantially increase produc tion. The yield pote nt ia l o f this land is close to that of the lowlands a nd higher than the upland (Figure 13 ). But serious proble m s n eed to b e solved before s uch a potentia l can mate rialize  -------------------------------  -------------------------~ \"'. Upland \"';\"};;\\i\\%1~;;,~~,.-. hydromo rphi c land with seepage waler durin g th e g row in g season a nd upper h~'d romo rphic la nd with <1 fiU ClU<1 tin g g roundwa ter tablC' withi n reac h of lh(' ri ce rOO ts. R ice yield s t(,nd to be hig he,-in Llll' law'!'."},{"index":30,"size":137,"text":"The basic prob lems aWecting rice p roduction in the lower hydro morphic la nds a rc adverse soil co ndi tions -a dcn cicncy of potassium and iron tox icity, bo th of which red uce yields. T he Iauer is <1 wid es pread problem whe re see page fl ows co main a high concentration of ferrous iro n (Fe + +) . SlUd ies co ndu c ted in 1985 showed tha t the iron LOxicity problcm is rC'lated to a nd worse ned b y potass ium deficie ncy. Ri ce and soi l scientists arc worki ng together to develo p a fie ld methodolog y for tC::il ing rice va rieties for tolC'rance to iro n toxici ty_ Several variet ies have bee n developed . (s('e Research /-lighlights /983)."},{"index":31,"size":158,"text":"Another problem is weed infestation w hi ch is mo re serious th a n in up lan d a nd lowland a rcas because of' unco m roll cd walCr conditions an d less leaf a rea of the ri ce pla nts. Resea rch is und erway to breed rice lines w hic h can co mpete with weeds in h yd romo rph ic areas_ I n a yie ld trial wilh eig hl promising lines in both upper and lowe r hyd romo rph ic land s ( Fi gu re 14), ITA 306 had the hig hest yield -94 8 and 7.+ I/ ha, respective ly -which was a tLrib~ ut cd to hig h to la l dry ma lleI' prod uction and harves t index. Th is va rie lY i ~ th e mOS l promising developed so I~lr by 1 I T A sc ie ntists for lhese lands."}]},{"head":"Depth of groundwoter table (em)","index":24,"paragraphs":[{"index":1,"size":3,"text":"-10 r----------~---____, ."},{"index":2,"size":34,"text":"Fig ure 14. Fluc tuation of the g ,-OlHtdw CLte r tab le at upper (UH) and lowe r (LH) hy dromo rphic lands at diffe,-ent phases of ,-ice g ,-ow t h ."},{"index":3,"size":114,"text":"V ast a reas in p a rts of Niger ia, Ivory Coast, Sierra Leo n e, Liberia, and Guinea g row rice under upland s ituatio ns with an annual rainfall of more than 2,000 mm and where high humidity, overcast skies, and soil nutritio nal imbalances often lead to discolored g rains -a major constraint in rice production . If not completel y fill ed , these g rains lower yields, and, even if fully filled , they may h ave discolore d k e rn e ls with poo r milling quality.  where ri ce lin ts 63-83, OS 6, a nd LAC 23 we r in volved as pan. 'nts."},{"index":4,"size":131,"text":"In tria ls over th(' pas t lew Yl'a rs by II TA a t seve ra l upla nd ('x perillll' t'JI a l siles a nd b th e :\\fa ti o na l Acce lerat ed Food Produ c tio Progra m (NA FPP) of Nig<Tia . thrl'c el itc lin es ITA 11 6. ITA 11 7 a nd ITA 118 -have shown promise for clea n g ra ins, good mill in g qu a lity blas t resista ncl', a nd hig h yields. Compared wit h th e loca l va ril'ty. as 6. th ey \\\\Ine distin ctl superio r in yidd and at leas t equal in th eir levd of rcsislanc(' to gra in discolo rat io n (T able 33)."},{"index":5,"size":29,"text":"L eft~ a rice v ariety w ith sev ere g \"{l in disco lo ratio n v s ITA J 17 w i th clean grains ( right)."},{"index":6,"size":281,"text":"Strategies to Combat Yellow Mottle Virus Disease in Upland and Lowland Rice U ntil1985, the potentially devastating rice yellow mottle virus (R YMV ) disease wa s r e porte d mainly in lowland r ice in Eas t , Centra l , and West Africa, but a joint survey co ndu cted by WARDA and UTA in Ivory Coast has revea led that it a lso occurs in s u sceptible exotic varieties und e r upland conditions. The r e fore, UTA's scientists have been devising strategies to combat this disease in upland as well as in lowland ri ce. From crosses made in ea rl y 1984, an initial St t orF:! lines were esta blished in 1985 and scree ncd fo r IOlerance to th e cl isl.\"asc and ror beller plant type. A tota l or 450 lines we re sc ree ned in R YMV endemic fields in the Republj cofN iger in field leSlS a nd at II TA in scrccnhousc ('valua ti on. O u t of th csc, 2 1 we re ro und to co mbine tolera nce a nd good p lalll type cha rac teristi cs. Indi vidual pl an t sd ec ti ons wcre made fo r f'u rlher yicld eva lualion a nd poss ib le refin ement in plant type and resistance. I rrA scientists arc co nti nu ing to widen lheir source for resistance to R YM V a nd have made init ial crosses lO explore the possibili ty or transrer ring lhe hi gh level of res ista nce of\" O. g/abrrrillla (TOg 567'~ and TOg 568 1) to O. saliva."},{"index":7,"size":32,"text":"A sensit ive sero logica l tecJllIique (EL ISA)jor identijjling rice line s with resista nce to R YMV. Fewe r yellow wells vertic ally :mean higher res,:stance to the v irus."}]},{"head":"Response of Lowland Rice","index":25,"paragraphs":[{"index":1,"size":279,"text":"to Applications of Sesbania rostrata Cuttings H igh yielding rice varieties r espond well when an additional s upply of nitrogen is added to soil , but th e high price of inorgan ic nitrogen fe rtilizers a nd their scarcity at the farm le vel at th e rig ht time are major co n straints for small ri ce farmers in various parts of Africa. The refore, the identifica tion of c h eap and r eadily available sources of nitrogen h as b een one of the major obj ectives of r csea r ch e r s at liT A.   Much oj the r esearch involves a .,nulti-disciplinary team approach by scientists in pla n t breeding, pa thology, en tomology, ncm atology, virology, bioch em istry, food tec hno logy, ph ys io logy, a nd ussu,' c ultulT . Scie Significant progress was made in 1985 to d evelop improved cassava varie ties that a r(.' hi g h yield ing a nd resistant to g reen spid er m ile. A hi g h yield ing a nd non-swee t va ri e ty o f sweet potato a nd 6 1 o thcr non-swee t typ es prefer red by m an y consumers in Africa wer e id en tified. New pro mising clones of bo th ,\"\" hite ya m (D. rotllnda/a ) and wa ter yam (D. alata ) ' were' produ ced , a nd resea rc hers id cnLifi ed several clones oC cocoya m (){anthosoma spp .) in Ca m eroon w hi c h a rc resistant to the roo t ro t complex."},{"index":2,"size":186,"text":"Cassava 111ealybttg populations were significantly r educed in lh e areas where lhe mOs t promising na lllra l ene my, I:./JidinocarsiJ IO jJczi, was successfu ll y es ta blished. Th ese a reas incl ud ed pa n s of N igeri a, Benin, T ogo, Za ire, Congo, and G hana. Explorati on activities cominued to be pursued o n the C M and CGrvl rro nts. One new C ~[ pa rasitoid (illlofro/!a , p. ) has been introduced and is undergoing bionomics studi es. Experi menta l rtic-ases wit h thi spec ies ha ve been ma d e in ~i gcri a. Za ire, a nd Sierra Leone. ~('w stocks of a ll previously introduced na lUra I enemi es ha vc been received to rencw 1I1C' gent ti ca I base of I rrA cu ltures A lso. new C ~\" and CG~1 na lUra l enemy spec ies have bec n found a nd an' currentl y being p rocessed in I he C I BC qu a ra lllin c la borato ry in Lo nclo n."},{"index":3,"size":159,"text":"i\\ rass rea ring tcc hniqu es for th(' C i\\/[ a nd its na tural enemies have been develo ped and ar now in th e produ cti o n ph ase, Up to 15,000 E. IO fJu.i can be produced d a il y in the au toma lcd insec l produc ti on systcm. Appropriate rearing technologics for use by nat iona l program have been designed and buill a nd are in the ex p erim enta l phase. Na tio na l biologica l contro progra ms ht; lVe been sta rted in Guinea Bissau. l vo ry Coast, G ha na, N igeri a , R wa nd a Za mbia , a nd l\\/( a la,• vi. Th ey received tec hnica l a nd fin a nc ia l assistance fi'om IITA. and many or their staff members were tra in ed in II TA/ F AO/OA u -STRC COll rses."},{"index":4,"size":76,"text":"A 1985fie ld survey of the impact of U TA improved cassava vm-ieties in N igeri a ' O yo SU:1lC' showed lhat th ese varie ti es account fo r abo ut 20 n 0 ora II cassava g row n th ere. They a rc also spreading in o ther N ige ri a n sta tes and in Za ire. C ha na. Benin. Cameroon. Sicrra Leone. Li bcria. a nd Rwa nda."},{"index":5,"size":62,"text":"I ITA-improved sweet POUllO varie ti es ped ormed well in Sudan. :\\ la lawi , R wanda. Sierra Leone, Gha na , Ca meroon a nd Solomon Islands. II TA varieties showeelea rl y bulking a nd hi g h yields und er hi g h a ltilud e ( 1,300 Ill ) co nditio ns in R wa nd a."},{"index":6,"size":158,"text":"Both cassa va 1110sa ic d isease (CN) D ) suscept i b it' a nd resista n t va ric l ies t ha I were freed from the d isease thro ug h rn erislelll culll! rc a nd ri gorous vi rus indexing were p ia n teel in the ficlel. I was demonstrated that a cassava \"a ri ety suscep tible to C l\\ 10 beca me read il y infec ted ,\\'ith the virus on ly two mon ths a ft er p la nting , while a resistant va ri e ty sho\\\\\"('c1 no d iscas symptoms fro m pbnLing timc up to nin e months a nel mainta in ed low disease inciden ce. R eciproca l g ra fting of low and hig h cya n id e cassava varieti cs showed Ih a l cya nid e I synthesized in 1I1 l'lcaves and tra nsloca ted illlU till' tubers."},{"index":7,"size":176,"text":"New seed ya111 produ.ction technology using prc-sprou ted minise lls a nd plas ti c mulch was ado pted by ma ny seed ya m g rowers in Nigeri a . Use o f' plasti c mulc h for ware yam prod uc ti on w itho ut pla nt sta kin g showed a 30°'0 yie ld in crease ove r convenlio nCi I produ ct ion sys tc ms with sta kin g. Further sLUdi cs may show th e possibi li ty of co mp1cu' t'!iminCltion o Sla king for ware ya m produ ction in the hi g h ra in fa ll forest zo neS. Experiments demonstrat('d tha t 80,000 to 100.000 seed ya ms per hectal\"l' (a bout 250 g rams each) can be produced unde plastic mulch and without sta kin g . ~r ore tha n 100 N ige ri an fa rmers adopted Llll' im pron:d seed yam produc ti o n system o n 120 hec ta r('s a nd found it pro fit ab le."},{"index":8,"size":191,"text":"\\tV a tel' ya m (Dioscorca ala/a ) breed i ng has no t been successfu I so fa r in prod uc i ng gena l ypc w i 1 h acce pta bl(' tu bel' shapes. bu I 12 ve ry pro misi ng new clones w i th accepta bl e tuber shape a nd yields have been produ cpd from hyb rid seed s for the first tinw since y <l 111 brecding work bega n at li T A a decade ago.  T wo syste tns oflIlass r earing of natural ene mie s of the ca s sava mealybug now in u se at lIT A involve diffe rent le vels of tec hnolog y a c cording to the specific purposes for whi c h they were d esig n ed. The firs t syste m u ses a dvanc ed t echnology for a c ontinuous ly hi g h and stable production of clean natural e n e m y populations, as well as for scie ntific r e searc h in rearin g t ec hniqu e s at UTA ."},{"index":9,"size":107,"text":"In eac h or eig ht stai nless stl't' l units , 600 sprou ted cassava cuttings ca n be fi xed in trays ho ld ing a nut rient solution and 111o \\'i ng around a ce ntrall y located lig ht so urce. \\ Vilhin IWO weeks (he plal1ls rea ch a hcig ht or 25 el11 with rive or six lea v('s pcr p la nt. T heil they a re a rt ifi cia lly infested wit h appro;.; im;' lI c iy 1.2 mi ll ion fi rst instal' mea lyb ugs (tlc rawil' rs\") i. e. a bout 2,000/cUl ti ng."},{"index":10,"size":162,"text":"As soo n as th e I'craw lers\" have developed into lilt' I hird imaar ( I hereby sto pping ,he p la nt g rowth ) approxima tely 5,000 rema le E. !opf'<.i a rc illl rodu ccd into the uni l an d all owed to lay the ir eggs into th l' mea lybugs. Al\"l cr two weeks of\" incubation , aboul 100,000 E. !olle::.;th e cassava mea lybug's na tura l enem y can be coll ec tcd rro m th e u nit ovc r a s{' vc n~d ay period . Ir a unit is loaded with cunin gs l'very week , a co nti n uous prod uc tioll or 20,OOO pa rasi loids pl'r da y can be ac hi eved . T his system is k ss labor intcnsive t ha n the classical insectar y wherl' plants, hos t inst'cts, and natural l' IH.' mi es arC' rea red se paral(• ly."},{"index":11,"size":186,"text":"An a lterna te, less co mplicau.'d. a nd lo\\\\'er-COS t sys tem built ent irel y f\"ro m loca ll y ava ilable materi a ls has bee n des igned ro r usc in nalion al biocom rol projects where elec tri c power supply may be irregu la r or un ava ilable a nd tec hn ical \" know-how\" a nd runds an: limited (Figure 16) . In this sys tem, 200 cassava cutti ngs ;\\1\"(' insert cd il1lo a venica l pipe. T he roo ts whi c h sta rt to grow il11 med ialt'ly inLO the substra te (sa wdust. pipe are irrig.w:d twice dail y with a nutrien solution rro l11 a n O\\-c rhead ta nk . T he resulting so-ca ll ed \" cassava tree\" is covcred by it fin nylon sc n:(• I1. T his keeps out un wa nt ed insec t but a llows enough light transmi ss ion a nd venti la Liol1 for grow th or cassava pi;) n LS to th e d es ired size in twO wee ks."},{"index":12,"size":132,"text":"The cass;]\\Ia p la nts arc artifici a ll y inr(,sted wiLh mea lybug \"crawlers\" and inocu la led with E. !ope;:.i in th (' S:1I11(' wa y as in the fi rst sys tem Seven weeks after p lan ting . a bout 10,000 pa ra SiLO ids can be coll ec ted at th{' top or t.h e unit The ••cassava Ire('s\" arc placed oli ldoOl\"S in a place of unres lri CLcd a ir move ment but protec tcd aga inst rain b y a transpa rent po lyet hylcne roof sh('c t. Fo r the mcalybug a nd pa rasito id phast.' of th e cycle, t he \" trees\" ha ye to bc l11ov('d i11lo a shad ed po rti on of th e she lt er."},{"index":13,"size":226,"text":"C nd cr thi s low-cos t, la bo r-intensive sys tem , mea lybugs a nd na tura l ene mi es a rc rea red witho ll t a ircondi tio ning in tropi ca l clima ti c conditio ns. T herefo re, co mpared with the mo re so p histi cated sys tem , ir is less efTi cicn t in terms of prud uctio n an d the o ut put of natu ra l enemies ca nnot be accu ra tcly predi cted. Du ring these rdcas('s, no hyptrpa rasiLO ids were broug ht li'om SOLa h America . Beca use their host is anol hlT parasilOici , th ey a n: co nsidered to be ha r mful to lh{' bi o logica l co ntro l program. One or th e main func ti ons oflhe su\" jet q uaranti ne com ra l therefore is to scr CL'1l lh l' fic ldcollected mat erial for h ypcrparasiLOici s a nd to remov(\" known species or this hahi t. For the Arric<'l-wi ck Biological Control Project (A BCP), quarantine is assured by the COlllmonwt'ah h I nstitute o r Biological Con tro l (e lBe ) an d approved by th e Nigerian Pl a11l Quaranline a nd th l' Il1Ic r-Arrican Ph ytosan iLary Cou ncil."},{"index":14,"size":402,"text":"Bu I E. 10jJl',z1 is now a I lacked by 10 ind igl'rto llS species or h yperparasitoids whic h have bee n n. . :cowTed rrom ('\\T ry Arri can co untry in \" 'hi ch the wasp was established and when' cX H.: nsivt mo ni to rin g co uld be-dOlle: CamCToon, Congo, Gambia. G hana, Guinl'a-Bissa u, ~igcria, R wanda, Togo, and Zaire. Severa l species we re a lso recove red rrom ot her coul1lri cs (in cl uding Senega l) berore the cs t::lb lishmertt o r E. tOj}f?i a nd in Gabon w here th e ' wasp has no t yet been rel eased , These h yperparasiw ids a re indigenolls Arrican insec ts attacking pa rasiLOids, ma inly o r th e ge nus A\"flgVrUS, whic h th e mse lves d evd o p in ot her meal y bugs. lik e the c losely related PhC lI(lCOCCIlS modeirew•is. Beca use h ypc rparasitoids, in general ; a re no t slrictly host-specifi c, th ey we re ab le 1O ado pt th e rreshly introduced   ( ce Research H ighlights 1984-. ) But \\vould lhe percentage hyperpanL 'i ilism cOllLin uc to grow in thc rutu re? Th e answer is \" no\" based on Ih e res ull s of rour large-sca le surve ys rrom M arch 1983 lO D ecember 1984 in so ulh,vcslcrn N ige ria_ The mea n pncclllage hyperparas itis m rell dramatica ll y Crabl e 35 and Fig ure 18 ). Fo r eac h gro up or insecls (pa ras i to id s, h yperparas i toids, va ri ous predators, l' lC, ), lht' sc ientists d ctermined th e mean number o r insec ts pCI' bunch l Op and til(\" pcrce m age orficld s wilh bUllch lOpS w hi ch yielded the panicular insec ts.     I n the rx pcrimcllls. scient ists used nod a l CUllings or 10 selected cassava varieti es obtained fro m I11CriSlCITI-cuiturcd p lan tlcts. The nodal c lillings were tra nsferred Ont O liquid cuhurc media whi ch contained diflcrent pH levcls (li\"om pH 2 fo r hig hl y acidic to pH 8 fo r sli g htl y a lka line). The co mposition ofLiw culture medi a for all treatments was csseJ1liall y the sa me."},{"index":15,"size":232,"text":"The.: perce ntage surviva l rate of nod al cuttin gs th a t exhibited notable grow th was ITco rd cd weekl y, a nd the leng ths of th e shoots tha t d eveloped from th e buds werr measured on the third a nd fifth weeks aftcr in oculation. Among th e 10 va ri eti es, there were va ri ctal diflcrcnces in optima l pH for the hi ghest pnccJ1l expla nt surviva l rate, but a Ll cassa va va ri eti es tested had more than a 40 0 / 0 su rviva l rate a t pH 5 (Figure 20). The number of va ri eti es th a t ex hibited more tha n this decreased with th e in crease or dccreast• in pH a bove or below 5. liD Only one \"ari ct\" (TMS 633397) had more th a n a 40°0 surviva l rate a t th e two extremes -pH 2 a nd pH 8 ; va ri elY TMS 60444 also survived at pH 8. The I11 can shoOl lcngthsofth(' 10 varietics incrcased with time a t all pH lcvels wit h the highest mca n shoo t length rccord ed a t pH 4 and the lowes t at pH 2. This indicated th a l high aci dit y adversely affected plaJ1l growt h substanli,dly."},{"index":16,"size":94,"text":"The tissuc culture tcchniq u(' ma y also be used in screcning for tolerance 10 other stresses such as sa lini ry a nd tolerance to chemicals. Further studi es a rc und crwa y to eva lu a te the practica l app li ca tion of this techniq ue. thereafter? The answer is \"yes\" if the whitefly (Bernisia tabaci ) which transrnit this virus disease is present and disease pressure (inoculum) is high in the field Depending on the susceptibility of the variety, cassava yield losses can range from 2 to 90%."},{"index":17,"size":65,"text":"Us ing a mcrislcm culture techniqu e a nd ri go rotlS virus indexing, II TA resea rc hers sel ec ted three vi rus-free va ri eti es -TMS 60444 (susce ptible), TMS 4(2) 1425 (moderately suscepti ble), a nd TMS 3000 1 (resistant). These va ri eties were then p lanted in IITA ex perimenta l field s with whiten y prese nce."},{"index":18,"size":73,"text":"As show n in FigUIT 2 1, the susceptible va ri cty beca me read il y infected with th(• virus only two mOlllhs a n cl\" pla nting (scored 2.5), and within four months the infectio n score was rated as se vere (3.7). Scores were determin ed at 2to 3-month interva ls using a sca le fi'o m I (no sympLOms) to 5 (severe infes ta ti o n sympto ms)."},{"index":19,"size":298,"text":"The moderatel y resistant va ri ety picked up til(\" infec tio n g rad ua ll y, scorin g 1.2 ill two mo nths a n er pla nting. It remain ed stab le for six mo nths, and th ell th e score in c n..'ascci slig htl y to 1. 9 w hen t ht• nex t ra in y seaso n bega n ( 12 mo nths after p lan ting). The res ista nt va ri cty showed no cassava disease sy mptoms from pla nting time up to nin e months. When the next ra in y season started, the scorl' climbed slighd y to 1.6. (N ew g rowth encollrag<'s an in crease in w hit efl y ac ti vit y). I n a fie ld ex periment, SCiClHislS tested combinatio ns of reciproca l stcm g rans a mong scio ns Scion and stocks or th e three cassava va ricti es -TMS 3000 1, TMS 30572, and T ~'I S 50395 -th a t co ntain low , medium , a nd hi g h cyanide. D espite a low cya nid e produ cti on in stocks u f TMS 3000 1 alld 30572, Lhl' scion ofTMS 50395 was consistcn tl y associa ted with hig h root cyanide content. Con ve rsel y, the hig h cyanide production stock ofTM S 50395 was associa ted with low root cyanide w hen grafted to low cyanide scions ofTMS 3000 1 and 30572 -proof that HCN is transpo rtcd fi•ol11 k aves to roots. La rger differe nces a mong scio ns th a n among stocks (T a ble 36) also imply that scions exert a stronger in fluen ce o n root cya nide conten t."},{"index":20,"size":70,"text":"FUrlher tr ials a rc und erway 10 confi rm th ese res ults, bUl it is clear th a t th e basis fo r selec tin g low root cyanide in cassava improve mcnt sho u ld i nclud e a morc accurate 1111'<IStl1T I11 ('n l of cyanide Ic vcls in roots and leaves in load y ge ncrati o ns. f r esh weigh t). •Ungrdj\"d."},{"index":21,"size":122,"text":"Yam Micro Tuber Production in Tissue Culture for International Distribution H and-carr ying tissu e c ulture materials -the usual method of distribution of virus free yam plantlets frolD lIT A to scientists in national programs -often results in very low survival rate because the p lantlets d e t e riorate if kept in the dark fo prolonged p e, riods of time. Furthermore, this distribution method has cre ated two othe problems for the tissue culture laboratories: t h e plant materials have to be r ead y and i s uffi c ient quantity at any time, and it is impossible to targe t th e quantity n e eded and th date of deli very of the materials."},{"index":22,"size":102,"text":"' ta rn mi cro LUbers produced in tissue cu lLUre oner solu lio ns to Lh ese prob lems. They ca n be se lll by ma il whi ch has no t been possible berot\"c. Also. they <Irc easier to handle w hen p lant ing, and, co mpared with pbnLiel.s j more of them survi ve . Scien ti sts produce lhe mic ro t ube rs by cu iluring nod e Clillings of the \\'irus-frec plants. Bf'C3US(,\" they arC\" virus-frN', qtlarantin e a u thori ties a pprove t he m fo r in ternat ional d istribution."},{"index":23,"size":112,"text":"Tubers ofdiffrrent shapes and sizes ha ve been obtai ned a t I ITA from a nu mber of va riClies of bOlh D. rot llnda/a (whi te yam ) a nd D. (I/a/a (watcr ya m ) pla ntlcts g rown in cu lLUrc mcdia fo r fOllr Illo rnhs. T ec hnicians remove the p lal1l -!tIS from the cu llUre co ntai ners asep ti ca ll y an d detach the mi cro tubers from the mot h er p lal1L fo r storage. T he nodal cutti ngs of the p lantielS arc Lra nsfern::d to fresh cuh urc medi a for further mu lli plica lion."},{"index":24,"size":63,"text":"The micro tubers sLOred in th e cul tu re medi a sprouted three LO four mO ll ths afler sLOra ge but th ose siored \\vithou[ cul ture med ia a nd uncin da,'k conditions sprou ted after six La seven mOl1lhs. T hL' storage duration is much longer tha n requ ired to reach most d es t.i nations by mail."},{"index":25,"size":84,"text":"The luberizalion of ya ms ;11 vitro was innu enced by the sucrose conce ntra tion in the c ultu re media a nd was hig hes t wit h a 5 0 '0 sucrose conce11lra tion. Sucrose concclllnnion hig her or lowe r th a n 5 0 / 0 d ec reased th e fr q uenc y or LUbcrizalion, indica u ng that lube iza tion ca n be manipu la ted by th is Itchniqu unde r il/ vi/fo conditions."},{"index":26,"size":21,"text":"Whit e yam plantle ts w ith Illi,,; tube rs g ro w n ill a tiss ue c ultnre ,neciiu.m.."}]},{"head":"Planting Density for","index":26,"paragraphs":[{"index":1,"size":78,"text":"Yam Microsetts G r owing pre.germinated 5 to 10 graIn m.ic rosetts und er plastic mulch can reduce the yam tonnage used as planting material as well as increase the Dlultiplication rate tenfo ld over conventional systeDls. The use of microsetts -small pieces of yam c ut from \" mother\" seed yams -does not only substantially c ut the farmer's cost for traditional planting materials but also saves an enOrmou s aDlount of yams for food in Africa."},{"index":2,"size":47,"text":"How many yam mic rosctls can be p lamcd per hectare with sa LisfacLOry results -50 1 000, 80,000, lOO,OOO? To fi nd OU t, scien tists CO I1ducted spacing experiments wilh 7-gra m mic rOscLts or the w hile ya m variet y TDr 13 1."},{"index":3,"size":45,"text":"The resu lts showed tha t as th e nu mber or LUbcrs per hecta re increased , th e ave rage tube r weight decreased, but yield per hecta re increased as pla nting d ensit y or mi crosclls was increased (Figure 22)."},{"index":4,"size":249,"text":"Th e relat ionship be twee n th e number or tubers per hectare a nd Luber .. \"eight showed Lila L a Lu ber wcig lll or a bouL 280 or 240 grams can be oblai ned when p lant densiLY is 60,000 a nd 80,000 per hecta re} res pecti ve ly. Resea rchers eS Limate th al tu ber weight wi ll be a bout 225 gra ms a t a plant de nsit y or 100,000 per hecta re. This means th at a n ad equate seed ya m weight might be achi eved eve n at a planting d ensiLY or 100,000 pcr hectare. I n the first tri a l with yam variety TOr 13 po lye th ylene plastic wit h the w hi le:' surface u was supnior 10 any other trea tnll' lIts both i !I._ TinS of Ih e mea n tuber size (606 g rams/tube a lld the ovnall yield at t he:' end of th t• season (22 L / ha ). T hese figurt's a re 50 0  0 highn th a thost' ac hitvrd fro ln th (' lraditio na l sta ki n me thod and more th an double those obta in ed from th e no sta king-no mul ch situa tion Cr a ble 37). The second best trea tment was ri ce stra w mulch with 500 grams/ tu ber and a n overall )ricld equivaltnt LO 18 l/ha."},{"index":5,"size":240,"text":"In th e second lrial , TDr 131 and a second Va ri l' ly TDr 179 were exa mined under polyet hylene pl asli c (with th e whi le sUlfa ce up) and a no mulc h situ a tio n. Each va ri ety was grown a l four plant populations ran ging li'o m 20,000 to 80.000 plants per hec ta re. At an y given plant population both the a verage siz e of the tubers and the total wbc r yield per uni l a rea was more th an 50 0  0 high er in the polye thylene treatment. T he superi ori t y of th e whi te plas ti c s urf~\\ C C is proba bl y du e LO a la rger lea f area ind ex and longer l e~d' area dura ti on which resul t in a hig her bulking ra te over a co mparati ve ly longe r period. Also, it ma y ha ve improved th e ligh t interception pa tt ern of th e plants. \\'Vh a lever the reasons, tWO Lhin gs see m clear: U nd er tropiOll co ndi ti ons, ntnncrs can ge t beller yields pcr hec tare if the y usc w hi le polye th ylene plastic mul ch a nd increase the plant d ensity of th e mi ni sc lls."},{"index":6,"size":111,"text":"LA ] • 1.4 Table 37. Effect of differen t mulching 2.3 materials; staking; and type of polyethylene mulch 011 w hite yam 1.3 ( IJiosmr('(I rolunr/ala) miniseUs. Plastic Mulch for Increased Ware Yam Production A lthough previous experiments showed that plastic mulching can help eliminate staking for seed yarns, the possible advantages of using it for ware yam production were not known. (Ware yams are large yams for marketing and consumption). Therefore, during 1984-85, lIT A scientists used plastic rnulch with or without staking and whole seed yam tubers (400 grams) for ware yarn production. They cornpared these treatments with the traditional system which uses staking but not plastic rnulch."},{"index":7,"size":65,"text":"Res ults? Plasti c mu lch gave 68 to 800; 0 larger tuber yield s co mparl'Ci with no IllU Iching (T ab le 38). Staking ya m vines increased t he yield by 20°0 compared with no sta king, bu t th e increase rar plasue mulch a lone was 39% mo re Lh an th e traditio nal sys tem (Tab le 39)."},{"index":8,"size":200,"text":"An cconomi c assess melll shows tha l ea ch addi tio nal Nigeri a n Naira spent in changing fro m traditio na l ya m farming to a mulched a nd sta ked o pera tion can earn a 3.70 Naira return . On the oth er hand ) eac h additi onal Na ira sp en t in cbang ing from tracl iuonal prac ti ce to the pl astic mu lch o peration withou t staking can earn 4.23 (T ab le 39). \\' ''hen plastic mu lc h was used , th e add itio na l yield benefits fro m addin g Slakes did no t oOsct the cost of sta king.  Contra ry to t he common belief th a t ya m yield is low wh en started later th a n Febru ary, the yields fro m th e plasti c mulch plOlS in th ese experim ents were ah .. 'ays hi g her than those from the un mulched plots rega rd less of t he plallling dates in Apri l, [Via)\" ju ne, and july, a nd the yields wcre not decrcased unti l june Cr able 38)."},{"index":9,"size":92,"text":"These re s ulL~ shou ld encourage th e usc of plasti c mul ch a nd qu a lit y seed yam to help exte nd th e pla nti ng season. Other ad va nta ges in cl ud e redu ced labo r for rid ge/ mo und preparatio n beca use of rai n sortened soil and bett er labor distribution beca use th e tim e of weeding ca n be adjusted to peri ods \\, ,, hen th e de mand for labo r is less.     "}]},{"head":"S","index":27,"paragraphs":[{"index":1,"size":42,"text":"weet potatoes -the second most important sources of carbohydrates as a dietary sta ple in Rwanda -account for about h a lf of the total root c rops produced. But production is not keeping pace with demands from an e xpanding population."},{"index":2,"size":177,"text":"Beca use loca l \"a ri cliesgrowll by farl11C1\"sa rc la l (, bu lki ng a nd sli sce ptible to sweet po tato vir us co m pl ex a nd 311lhrac nosc, IITA a nd na rio na l sc ientists have tes Led a nd se lec ted lin es tha i arc earl y bulking and ad apted lO va ri ed agroecologies where l h e crop is grown. In a r ('CC Ill sur vey, rarmers in R wa nd a repon ed th a t ea rliness was by far the most preferred charac teristi c for sweet pota to lines. followed by ad aptab ilit y LO th e so il , hig h yield , good tastc, a nd rc-sista ncl' to wt:evils a nd droug h l. A commo n co m me nt heard in R wan d a is \" late bulking lin es arc for th e r ich beca use on ly th ey ca n a Ho rdto wa il. \""},{"index":3,"size":188,"text":"Fi eld tests were co ndu cted in 1985 in six d iflc rt llt ex per iment sta ti on en viro nm ents a nd at seven off-sta ti on Sill'S represe ntin g a w iclt: spectrum o f swee t pot atO p rodu cti o n a rea s ra ng ing from lowla nd ac id so ils lO hig h a lti tuclt.:. Thl\" lin e DV 16/820 was the bes t wit h a mea n yie ld o f 12.8 t/ ha a nd with good ad a p ta lio n to a wid e range of cnviron men ts. I t a nd th e ot her hi g h yie lding ca rl y li nes a t th e six sta tio ns Cr a ble 40) consiste ntl y r emain ed th e hi g h yiel ders in th e ot her les t a reas. They a rc bein g multi p lied fo r d istri bu tio n to farmers a nd colla bora ti ve proj l'c ts."},{"index":4,"size":1,"text":"120"},{"index":5,"size":224,"text":"Th e e lite sweet potato line D V 16 820 (rig ht foreg round) had the highes t yields i\"field tests in six diffe \"e nt e nviro\"me nts in R w anda j TIS 2544 (left) w as second.  Among th e sweet potato lint's tes ted for yield at IITA in 1985, thrce had low LOwl suga r conce ntration evcn ahe!' ba king (Table 4 1). T Ill: suga r COIlCl' lllralion in crl'ascd vt' ry little afit'!\" bakillgduc LO low conccl1Iralio n a nd /or aC li vit y orthe am ylasl' enzy mes whi ch convert starch to sugars during th e initial peri od of cookin g.    The p erce11lage o r unm a rk eta bl e TI b II tubers p la n ted a nd ha rvested la te was as hig h as 42 0  0 co mpared with o nl y 5 % of the improved a nd mod era tely res ista nt line T IS 2532. H owever , prelimina ry res ul ts show th a t th e integ ra Lion o f improved lin es mod era tely res istal1l to weevils with ca rl y p la nting and ha r vesti ng a nd re-ridgin g produces th e bes t ove ra ll results."}]},{"head":"International Cooperation and Training Program","index":28,"paragraphs":[{"index":1,"size":84,"text":"A m ajo r res ponsib ili ty of UTA is to d eve lop effect ive linkages with nationa l a n reg iona l prog ra ms to ensure tha t th e techno logies developed through research reac the po tentia l benefi cia ri es ~ Ca n n ers a nd consumers. Co ll a borati ve projccLS an co m p re hensive tra ining programs a rc prin cipa l instruments to ac hi eve this goal."},{"index":2,"size":97,"text":"Current policy calls for a n in creasing number of resea rch and tra in ing progra m acti vitie to be conduc ted ou tsid e the fnst-inile's headqu a rt ers in Tbadal1 , N igeri a so fhaL loca l specifi agri cultura l p roduction pro bl ems ca n be a d equ a te ly tac kled. Among the act ions ta ken wa the es tablishm en t of a substa tion in the R epub li c of Benin and officia ll y d edica ted I September 1985_"},{"index":3,"size":249,"text":"During the year, IlTA parti cipated in collaborative p roj ect aC li viu es desig ned L stre ng then na ti on a l/ regio nal resea rc h ca pab ili ti es in nin e o th er Arri ca n co un tries C a meroon, G hana, K en ya , N iger, R wand a, Sierra L eone, T a nzania , Zaire, a nd Z imbabw An expanded progra1n in Zaire provid es assista nce to a proj ect d esign ed to in tegra susta in the resea rc h a nd techni ca l manpowe r capab ili ties of tha t country to d eve lo tra nsfer agri cullUra llechno logics ,\"\" i1l1 e mph as is no t onl y o n cassa va but a lso o n mai gra in legumes. Previously, I ITA in volve mcnt in Za irc \\, vas limited to cassava . The scientific tea1n in R wanda is engaged in th e selec tion of c ro ps/ya ri e ties a d cvr lopmc n t a nd les Li ng of croppi ng systc ms ada pta ble to t he se mi-arid co nd i Dons in a reas of tha t country. In addiLion, assistan ce is provid ed for the d eve lopment o f a Rwa nda n natio na l cassa va a nd swCC t POtatO improvemen t progra m ."},{"index":4,"size":107,"text":"In Sierra Leone , lITA initiat ed a progra m o f assista nce for the d evelopment o f s tec hno logies in soil a nd c rop mana<Yc lllent [or intcnsive utiliza tio n of inla nd va ll eys fo based fa rming systems by lo\\v reso urce fa rm ers in \\JVesl Afri ca. This aC li vit y is pa rt of Afri ca-\\• vid e progra m for we Liands d e velo pmenl. Simi lar activities arc und crwa y in th a rea of N igeria a nd plann ed for the R epub li c of Benin."},{"index":5,"size":78,"text":"A prog\"am on the other side of Africain Tanzania -is d esigned to develop colla bora tio n wilh T a nzani a n na uona l a nd ot her E as tern African resea rc h o rga ni za L testing a nd eva lu a ting cowpea produ ction techno logies , Also. it seeks to d evelo p L progra ms for agri cullllra l manpower d cve lopm ent in the region."},{"index":6,"size":101,"text":"IITA co llaborates with CIMMYTin Zimbabwe in the d eve lo pm ent of a maize ing progra m to genera te gcrmpl as m ad a ptcd to mid-a ltitud e areas w hic h can be exch on an Afri ca-\\vid e basis. The Instillllc is a lso in vo lved in the de vclopmcnt of\" a re resea rch progra m for gra in legumes with maj o r focus o n vari eties resistant or tO le-rani L stresses a nd technologies for cropping sys tl' ms suita ble for countri es in Sou lhern Afri c"},{"index":7,"size":48,"text":"Research support continuedfor SAFGRAD 's regionalrnaize and cowpea irnprove rnent program for 26 countri es in the semi-a riel tro pics of Africa stre tching across th sOllth ern ed ge of th e Sa hara desert a nd clow n to the southern part of the continent."},{"index":8,"size":80,"text":"A ltogc lh cr J 42 1 ITA scien tists have been assigned to countr y a nd regiona l progra ms in Africa, Sou theast Asia, and La tin America to ass ist wi th the d evelopment of comprehensiv programs for (,va lu ation a nd a d option o f improved gcrmp lasl11 for ma ize, rice, cow-p eas soybeans, cassava, S\\v('c t pOl aLO, ya ms, a roid s and improved fa rmingsyslc ms techno logy."},{"index":9,"size":89,"text":"Current training strategy ca lls for a gra dual shi ft fro m offering practi ca ll y a ll tra inin cou rses at I ITA's headqu a rters LO scheduling the m in va ri ous countri es with a n emphasis o regional coverage . The lnstiwte provid es assistan ce in streng th ening inSlitlllion a l capa bi li ties w ithin nat io nal /reg io nal progra ms 1O enab le their personnel LO ass ume th es res ponsibiliti es ."},{"index":10,"size":141,"text":"During the yea r, 28 group courses \\ VC IT condu cted a t II TA a nd in the R epublic of Benin Sierra L eon e, R wa nd a, Bra zil , and the Philippin es. Out of the 678 persons who attend e them , 100 were participa nts in off-site training ac ti viti es and th e re mainde r in Ibadan-base courses . Th e maj or focus of thcsc grou p courses was researc h and production tec hn ology fo a ll c ro ps in the l nsti tute 's ma ndatC', plus sp ecia lized LOpi cs such as wecd control, soil an pla n t a na lys is, so il a nd water conse rva ti on , and statisti cs in ag ri cultura l cxperimentati on."},{"index":11,"size":118,"text":"Throug h degree-re lated rra ining progra ms, supervisory suppOrt was provid ed for 34 i\\J .S a nd 28 Ph.D. candidates fro m 14 a nd 12 Afri ca n countri es. rcs pectivrly. These gradu at stud ents a re engaged in the thesis resea rc h compo nent of the ir university degree wo rk . Thi a rrangement ensures that the yo ung resea rchers bendit fro l11 the experience a nd expertise o lrrA 's senio r resea rc h scientists. At the sa me time, it enables LiH.' scientists to expand th e ca pacity for mo re in-d epLh resea rch with the ass istance o f these yo ung scientists."},{"index":12,"size":107,"text":"In addition to providing training opportuniti es fo r 13 pa ni cipants from fi ve POrluguesc speaki ng Afri can countries, the I nstitute provid ed a forum to furth er id entify specific areas o need ro r ag ri culturallra ining for nat iona ls from Guin ea Bissau. Angola , iVl oza mbiqu e, Sa Tom e, a nd Cape V erde . As a resu lt of the d iscussions at a roundta ble at lJTA head q u a rters pl a ns were d evelop ed fo r a comprehensive training progra m for Luso pho ne Africa countri es."},{"index":13,"size":93,"text":"Thirty-r' vvo agricu ltural technicia ns a nd stud ents we re train ed through non-d egree relate and vacation stud ent scho la rship programs. Their prog rams werc d esign ed to respond to rh d emand LO help improvc the agri cultura l tec hno logy resea rch a nd producti o n skills o employees or d epartments a nd ministri es of agricu ltll lT, interna ti ona l orga ni za lions, priva t age ncies, a nd uni ve rsiti es in Africa a nd elsewhere."},{"index":14,"size":132,"text":"The overw helming proponion of the 740 pa rti cipan ts in a ll trainjng progra m ca tegori e during 1985 \\• ve re from Africa . For the first time, however, pa rticipa nts ca me fro m Cap V erde , Nepa l, Ireland , th e Baha mas, Bo livia , Ec uador, IVI cxi co, Pan a ma and Pa raguay. onlin e bibliographical da tabase which was named ALISTRA. At the end of 1985, this da ta base had a bout 40,000 records. The system has a la rge number of fi elds that can be searched online . These include authors, all keywords in the titles o f publi cations, subj ect descriptors, publishers, corporate sources, publi cation el a les, and keywords in abstracts."},{"index":15,"size":96,"text":"T aking ad va ntage o f the auto mated system , libra ry sta ff me mbers now supply to scientists and senior management lists of new books and journal articles which ma tch their specifi c interes t profiles. This service, known as Selective Dissemin ation of Information (SDI ), has proven to be useful to all concern ed . Automation orlhe librar y also permits fast compilation of bibliographies on va rious subjects, wh et her broad or hig hl y spec ia lized , to meet the demands of scicntislS and trainees."},{"index":16,"size":177,"text":"When lITA purchased the computer soft wa re package fo r the system (called BASI S), negotiations we re completed so tha t other CGIAR centers could obta in this ve rsatile da tabase ma nagement system a t a discount. T wo centers (eIP a nd ICRISAT) d ecid ed to do so, a nd I ITA will help the former insta ll the system in 1986. Th e usc of the sa me software package (BAS IS ) on the sa me VAX computer will facilita te collabora tion and exchange of\"  One ofthl' virologists spent a year on sabbatical leave at the Asian Vegetable R esearch a nd D evelopment C enter (A VRDC) in Taiwan and at the R esearch Institute for Plant Protection (IPO) in the Netherlands to make a n in-depth stud y of swee t potato viruses. A sound knowledge of various vi ruses present in different countri es is considered essential to be a ble to develop indexing methods for the exchange of germp lasm on a global scale."},{"index":17,"size":56,"text":"Although various potyviruses have been isolated from sweet potatoes in T aiwa n and other countries, very little is known with certainty regarding their role in the etiology of known virus d iseases in this crop. In add ition to the aphid-borne potyviruses , the occurrence ofwhit efly-bome viruses has been reported from various coun tries."},{"index":18,"size":184,"text":"The aim ofa more detailed stud y of the whitefly-borne ' leaf curl' disease in T a iwan was to iso late and purify the causa l agent and/or to develop a reliable testing procedure for this virus, and to investigate its possible role in the etiology of (virus) diseases otherthan 'leaf curl' reportedl y occurring in this crop in Taiwa n a nd possibly other countries in the Southeast Asian region. By means of whitefly transmission to Ipomoea selosa, as well as to true seedlings of sweet potato, various virus iso lates were obtained from plant samples taken from obviously virus-infected and symptom-showing sweet pota to plants. Most of the isolates obtained in this manner only proved capab le of indu cing leaf curl-like symptoms of varying degrees of severit y in sweet pota to seedlings, whereas 1. selosa proved hig hl y susceptible to a ll isola tes obtain ed in this mann er , deve loping characteristic a nd severely stunted growth and yellowing symptoms. Thus, the ind exing for this virus is very reliable by grafting to 1. se/osa ."},{"index":19,"size":76,"text":"Severa l aphid-borne and sap-transmitted virus isolates were obtained from diseased sweet potatoes and from the common weed species, 1. Iriloba and 1. obscura, showing various kinds of virus-like symptoms other tha n those of typical ' leaf-curl '. None of the a phid-borne and/or sap-transmitted isolates proved capable of inducing disease symptoms of the kind and severity observed in diseased pla nts of the sa me local varieties from which disease samples were originally taken."},{"index":20,"size":34,"text":"Mutual , serological comparison of six sap-transmitted isolates from sweet potato obtain ed in NicoliOlla benlhamiana have shown that a ll a rc closely rela ted and possibly id entical (virus II ) ."},{"index":21,"size":90,"text":"Serological studies have also revealed that none of the virus isolates obtained from sweet potato through sap and aphid transmission , either in N . benthamiana or 1. setosa, represent viruses which are serologically related either to FMV or SPV-N, the latter being a poty(?) virus which bas so far been described from Taiwan only. Indexing for the newly isolated potyvirus (Virus II ) may be done with the antiserum prepared for this new and possibly h.itherto undescribed virus of sweet potato which was successfully purified from N. benthamiana ."},{"index":22,"size":86,"text":"New potyvirus isolates o btained fro m sweet potato in Nigeria were also purified and antisera produced. The virus isola tes from Nigeria reacted with an antiserum against feathery mottle virus (FMV) •from the United States. Simjlari y, diseased sweet potato samples from Nigeria when tested in ELISA using FMV antiserum gave a positive reaction. I t is concluded that the aph.id-transmitted component of the sweet potato virus complex from Nigeria is similar or identical to the FMV reported from the U .S. and other countries."},{"index":23,"size":114,"text":"In Zaire, some of IITA's improved and CMD-tolerant cassava cultivars showed prominent symptoms of cassava mosaic. To identify this disease and compare the cassava mosaic disease from Nigeria with that from Zaire, comparative studies were initia ted a t IPQ . Using the antiserum produced a t liT A , samples from Zaire were compared in ELISA. Some samples from Zaire showed mild er sympto ms on N . benthamiana and proved serologicall y different. The knowledge of the d ifferent types of cassava mosaic virus and their distribution is considered essentia l for developing widely adapted and resista nt cultivars. Further work on characterization of the isolates from Zaire is in prog ress."},{"index":24,"size":47,"text":"Because cowpea aphid-borne mosaic virus (CAbMV) and cowpea yellow mosaic virus (CYMV) are economically important constraints, the research activities during 1985 included the collection a nd identification of different isolates a nd a study of the relative importance of various types as far as resistance is concerned."},{"index":25,"size":48,"text":"For selecting better sources of resistance to rice yellow mottle virus (RYMV), scientists coupled visual assess ment of symptoma tology with comparative virus antigen concentration as determined by ELISA to differentiate resistant/tolerant lines. They found that some Ory;:a glabeTTima and O. barthii accessions are immune from this virus."},{"index":26,"size":111,"text":"A few viruses are reported to be seed-transmitted in cowpeas and soybeans. Therefore, information on seed transmission of severa l viruses has been updated. Extensive screcnhouse a nd laboratory tests showed no seed transmission of cowpea yellow mosaic virus (CYMV) in cowpeas. This finding is contrary to previous reports. Similar results were obtained when seeds collected from cowpea mild mo ttle virus (CMMV) infected soybean plants (M a layan variety) were sown a nd the seedlings were tested in ELISA, but a ll proved to be nega ti ve. H owever, other soybean lines will be tested before concluding that there is likely to be no seed transmission ofCMMV in soybeans."},{"index":27,"size":30,"text":"In screening ad vanced soybean breeding lines, using the standard and a severe isolate of soybean mosaic virus (SMV) , several lines were id entified as resistant to this virus."},{"index":28,"size":324,"text":"An outbreak of maize stripe virus a t UTA fi elds was positively identified by transmission tests by Peregrinus maidis to the same maize lin es which showed symptoms in the field. Th.is was aga in confirmed by serologica l tes ts usin g antisera li'om the U.S. V ario Lls parent.s used in the breeding program are bein g screened against ma ize stripe virus in coll a boration with pa thologists a nel plant breeel ers. In collaboration with entomologists, 8,265 accessions of cowpeagermplasm wer evaluated ro J' resista n ce to pod suckin g bugs al ! Vl o kwa , N ige ria , a nclthe bes t ofth l'sC ' wer sel ected fo r further screening. Also, in coopera tion with viro logists, 27 accessions or Vigu vl!xillala (a \\vild cowpea species) were screened for resista nce L a cowpea m OLLIe \\•irus. Almos all of the m wen: immune. So fa r, scientists have no t round good sources o f resista nce to thi yirus in cuiLi va lcd cro ps. During 1985, crosses \\\\l e fT mad e between culti va ted a nd wil species, but these crosses were unsuccessful. Cross-pollinated flowers in va ri a bl y abo rte within two d ays a n tr pollination . H owever, resuiLs o bta in ed with hormones on HO W l ... bud were encouraging. Trea tm ent \\\"\"ith 6-bel1 zy l a mino purin e (BAP) pro longed the d evelop ment or yo ung hybrid pods for up to 12 da ys a rt cr pollina tion ; then they abo rted. Studi es o e mbryo culture to reScue the imma ture embryos fi'om these crosses a rc continuing , as a r long-term ex periments on the efTects o r chcmica ltrea tmcnts on cowpea seed longevity und e diffe rent te mpera ture a nd moisture conditions. Unit. "}]},{"head":"More cotnplete inform.ation on the topics m.entioned in this Executive","index":29,"paragraphs":[]},{"head":"More complete information on the topics mentioned in this Executive Summar can be obtained by requesting the Annual Report of the Genetic Resources","index":30,"paragraphs":[]}],"figures":[{"text":" qual-ters at [badan , Nigel-ia ; the ntai1l caJnpus 0 11 tlte right w ith. laboratories, offices, and housillg is stu -rouuded by the expe l-ilnental f\",.,.n s ; OIl the left a c ,\"OSS the lake (the [nstil.llte's w at.e r supply) are '-esearc h plots c lea re df,-o mfol-es t lalld. Introduction to IITA E stab lished in .Jul y 1967 as till' first m ajor Afri ca n li nk in a n int egra ted nc two rk or internatio na l researc h a nd training ccnL t: rs located thruug ho ut the ck vclo ping regio ns of lilt\" world , the Int erna ti o na l Institut e of Tro pica l AgricuiLurc ( l1TA ) is a n 3ULOI1 0 m OllS, no npro fit corpora ti o n w ith headqua rters o n a I,OOO-hec ta re experim ental flll'nl a t Iba dan , N igeri a in close proximity to the U ni versity o f Iba d a n . lI s loca ti o n l~l c ili taLcS rl. "},{"text":"Funding: • Publish and widely disseminate research findings to scientists, policy makers, national research programs, development and extension personnel, and others. • Provide an information center and library with a comprehensive coll ection of world literat ure on Lropical agricu lture for usc by scientists and scholars. Principal finan cing of the Institute is arranged through CG I AR -Consultative Group on International Agricultural R esearch. (See inform ation on CG IAR beginning on page 9. ) Fin ance and support during 1985 for II TA 's research a nd training was provided by the fo llowing int ernational agencies, foundation s, and nationa l governments: Canadian Internationa l D evelopment Agency (CIDA), U nited States Agency for Internationa l Development (USAID), World Bank , Ford Foundation , Rockefell er Foundation, O ve rseas Development Administration of the United Kingdom (aDA), Austra lia, Belgium , Denmark , Federal Republic of G erma ny, France, India, Ita ly, J apan , Netherlands, Nigeria , Norway, and Sweden. In addition , other donors provide funds to [ITA to support specific research proj ects or training progra ms. Staff: The Institute has nearl y 200 principal sta ff members who come from more than 40 countries. UTA also emp loys over 1,000 support stafT, most of whom arc from Nigeria. The majority of the Institute's scientists are located at headquarters but some have been assigned to IITA substations at anne, (Nigeria) and at Cotonou (R epublic of Benin) and to projects in collaboration with regional and national programs. (See th e Annual Repon Executive Summary of the International Cooperation and Training Prog ram beginning on page 123. ) Agricultural Research (CG I AR). Th e purpose ofthe research e[fort of 13 centers (in cl uding II TA) now in the CG IAR system is to improve the qua ntit y a nd qua lit y of food prod uctio n and the standard of living of people in deve•loping countri es (Figure I) . They focus their resea rch e[forts on crops a nd a nima ls which provid e a large part ofthc food suppl y o l\"th eir respective regions. The international centers have a var';ety o/research interests . Eight concentrate o n pla nt breeding fo r o ne or mo re cro ps. Nine a rc in volved in agrono mic research, t wO d ea l wil.h L ivestock , a nd two include major prog ra ms a imed a t improvi ng pas tures and forage crops. One center, IBPGR , d evotes itself exclusively to the collcction and conservation of gcnc Lic ma teria l ; ano th er, [SNAR , works w ith agri cultural research agencies in developing countri es to provide advice to governme nts o n wa ys to streng th en agricultura l rcsea rch, and a third , IFPRl , studi es the econo mics of food produ ction to o[fer rccommendations concern ing policy ch a nges need ed to promo te adequate and sustained growth. "},{"text":" Trustees on w hic h members, c hosen for th eir experience a nd experti.~c , serve in individu al capaciti es. Th e board determin es th e direction of the cen ter's research , but this is done in th e fi'amcwork of interna tional consulta ti ons on two l cvcls ~o n c scientific a nd th e other fin anc ia l and administrative. "},{"text":" netwo rk o f interna ti o na l agri c ultura l research institutes covers th e humid a nd subhumid zones o f th e world , its primary res po nsibilit y res ts in sub-Sa ha ran Africa, th e region o f th e wo rld \\\\Ihcrc the need is most acute . D espite th e seeming ly ove rwhelming difficulties tha t must be overcome to improve lhe situ a ti o n, th ere exists a t IlTA a n optimism and encouraging realism abo ut th e na lUrc of the cha ll enge . N o o nc sho uld ad va nce misleading ho pe th a t Afri ca will experi ence a ngrcen rcvo luLi o n\" simila r to the o ne so widely public ized in Asia. Afri ca's traditio nal agri culture is much mo rc complex . The dra matic breakthro ug hs in Asia with rice and w hea t were based o n "},{"text":" E.H . H a rtma ns, is paying di vidends : new improved varieties d eveloped by our scientists have been tested by na tional prog ra ms and re leased to farmers in man y countri es. As a result, yie ld s of several impo rtant food crops have in creased and become more stable. M o reover, improved farming systems tha t integra te traditiona l a nd mod ern emerging technologies arc g raduall y being d eveloped a nd tes ted in on-farm trials. I call your a ttentio n to severa l a rticles in this vo lume: th e d evelopment o f dro ug ht to lera nt, disease a nd insect resistant vari eti es o f various c ro ps; th e progress in a lley farming as o ne o f th e a lt erna Li ves to th e centuries-o ld shifting culti vatio n w ith its rela ted bush-fa ll o w ro ta ti o ns; new extra-earl y ma turing maize vari eti es fo r th e Fores t and Sudan Savanna o f'N es t Africa tha t ca n fill the (ood sho rtage during the \" hungry ga p\" between the tailend offood stocks o f the previous season and the ha rvest of the la ter ma tu ring food crops; performa nce of hig hyield ing rice vari e Lies ada pted to vario us Arri can eco logies; a nd th e d evelo pme nt o f a n effi cient means to produce yarn pla nts in in vitro ti ss ue c ulture ro r interna ti o na l distribution . These and o ther exa mples d escribed bri eRy in this publication represent onl y a po rtion of I ITA's accomplishments. "},{"text":"• Dr. 5 /{{r1 niSl/llltd rts/HJluiMlilJ' ns Dim/or Gll/t'm! ill Or/ob,r J985. "},{"text":" conclusion , I must mention that o ur Boa rd of Trustees has been streng thened by the add ition of two new members, NIl'. J ohn D. Edoz icn ) Permanen t S('CITtary of the Fed era l ~/li ni s try of Agricullure, \\'Va ler Resources and Rura l Developmen t in Nigeri a, and Dr. ~I ayra Bu vi nic, Direc tor of' the Int erna tiona l Cent{'1' for R esearch on \\'Vomen in \\Vashi'1g ton D .C. As a woman a nd social scientist, Dr. Bu vinic wi ll bring long-n eeded perspecti ves to th e d eliberations of our Boa rd. At thr same time, IITA los t the servicl's or fo ur dedica ted a nd va lued Trustees vJhose terms of service end ed: IVlr. Dominic E. I ya mabo, Vice-Chairma n orthe Boa rd ; Dr. Ro ben C, M cG innis, C hairm a n of the Program Committee ; Dr. Hid ctsug u lshikura and Mr. Pa poola. The Boa rd of Trustees gralclldly ac know ledges their enduring contributions to the work orthe I nstiwlc, and I am sure tha t we will con tinue to look to t hem for wise counsel in fu ture years. Annual Report Executive Summary Farming Systems Program A IllUhi-ciiSCiP li na ry ellon . fa rming systems researc h is a imcd ::H d c\\'d oping appropriate tec h no logica l inn onlt ions LO increase a nd sLista in produ c tion or food c ro ps d esig nat ed in )I TA's ma nd ate, Its sc ientists stud y th e bio logica l, ph ys ica l a nd soc io-C'co no mic fa c lo rs th a t affec t the agri c uilura l produc ti on of sma ll-sca lC' fa rms ill thl' humid and subhu III icl tro pi ca l regions of sub -Sa ha ran Arri ca. During 1985. the program at hcaciqu a rLefS consisted of 16 core-fundl'd scie ntists working i 11 fOll r rcsca re h I ('a ill S a !lei o ne sp ccia I II ni 1 : II pi a !lei p roduc t iOIl sys tems. \\Ve tl a nd prod u e l io n sy~I (, Jl1 S . ag rofo n 'sl r y a nd p la nta in rcs('a rc h 1 o n i: lr m researc h, a ncilhc soc io-econo mi c L1 llit. "},{"text":" Lh a L 88° 0 o rLh e children k ll bd ow Lh e 50Lh pcrctrllilc o rLh e weig hL a nd he ig hL minimum 1' 0 1' age ) a nd a t leas t 30 0 0 sul1c n:d rrom severe ma iTllllriti on. A soybean d emo nstra tio n p lo t was eS la blished a t O g bomos ho to test yields a nd syste mati call y introdu ce wome n to producti on techniqu es. A K ersey stafrmember was seco nded to the Socia-Economi c Unit LO work full time on soybea n uLili zation \\\",iLh na tio nal collaborators rro m government ministri es. A multi-discip li na ry tea m und cn ook a n exploratOry survey of compo und (ho mestead ) ra rms in eastern N igeri a . It was d esig ncd a nd implemented in colla bo ra tio n with the U niversity of ~i gcri a a t Ns ukka , the f o restry Commission a t Enugu, ~II ichael Okpara Co ll ege o r Ag ri culLure a L U muagwo , and I mo La L l' AcceleraL ed Develo pment Area Proj ec t. Th e stud y listed a ll p la nt speck•s. d ocumented the impo rta nt nutritiona l va lu e of roods a lld ITl'e S in th e compo und s) and prepa red a mod el d escribing fi ve types or compo und fa rms a nd plant distributions according to eco logy a nd populati on d ensity. "},{"text":"I n semi-arid environments with lirn..ited rainfall and hi g h soil water losses through runoff, c u lt ural prac tices that redu ce t h is runoff are essentia l for more stable yie lds. Tied ridges, introduced a few years ago in Burkina Faso (form e rly Upper Volta ) by IITA/SAFGRAD scientists , help m eet this need. (See R esea rch Hig hligh ts 1981.) T hey redu ce runoff, improve soil water reserves, a n d markedly inc rease grain yields of s evera l c rops, including rnaize and cowpeas. "},{"text":" l'('s p('c ti\\\"l ' I ~, Produ c tion costs are ('stimated at 1+.000 a nd 16,000 CFA. "},{"text":"Figure 2 . Figure 2. Majo r c ropping sys te nts in rainfed area s near Bida l N ige ria plotte d against 1985 m onthly rainfall. "},{"text":" H O\\\\l('vtT, ot h {'r qu a li li ('s of' impro ved rice \\'ar il, ti l's will be ('\\'a lu a l('d for seed l1lultiplic.ui o n a nd d islI•ibUli oll . lTil't)' manag(\" Illl'Il ' * m:magt.'lIwllt** \\I (y s p ecies -A c ioa bm \"te ,.i (C hrysob a la n aceae), A lc h orn e a c ordifo lia (E uph o rbiaceae), G liricid ia sepi'll111. (Papili o n oideae), and L e'Uc ae na le u cocepha la (Mi mosoideae) -we, r e evalua te d fo r th ei r p e rform a n ce in a lle y c r o pping o n d eg' ca d ed la nd a t UTA. D espi te a h eavy pruning r egime -five eac h yea r s in c e 1982 -a ll fo ur s p ecie s stil l s h o w e d vigorou s coppic ing a fte r pruning a nd produ ced s ubstan t ia l a tn o unts o f dry m atte r a nd nu t ri e nt yield (T a ble 5). "},{"text":" Ario{l a nd AIr/lOme(f are in d igenous wooely specits cO llll11on ly p lan tcd o r St' l\":c li\\'e ly rCla in l'd b y Ihe tradi tion a l Et rmers in bush fa ll ows in th e h u mid zOll e o f N iger ia . Clifiridin sepiulfl illlrod uccci into the .\\ fr ican cQmin c nt a long time <lgo as a n u rse crop fo r cocoa is a lso widely g row n b y tra di tio na l farmers fo r so il f(• nili ty im p rovc l11('1lI a nd for ya m slilki ng, T he g iant L I'II((1(,IIf1 /(,II(orrp/w/n (va ri cty 1\\.-28 1 used in the tria ls was int rod uced from H awaii dur ing Ih,' \"arly 1970s. H ed gerows o f LiH. 'S(' wood)' sp ecies, plant ed + 111 apa rt o n an eroded AI1I501. W(Te pruned back to a he ig ht o f 75 c m to pro vid e mu lc h a nd g rce n man u re fo r th e co m p:tn ion fClod crops a nd :11 I he S'I I11I.' ti 111 (' pn'\\'('n t sh:lding: crop pi ng sequence uSl'd consistl'd of mai ze foll owed b~ cow peas. "},{"text":". \\ 11(')\" cro pping d Cll1onsll'a ti o ns and 0 11 r~lI' l1 t ri:i1 !i lIsing L ruwellfl /('u(orejJlw/o and C/iriridin se/Jiul1I Wt.TI.' a lso ca n ; cd out o n d cgrach-d E m iso ls in the dni v('d sava ll na h o f SO Udl t T I Ta ble 5. Dry m u tter (p ruu ings) and nut r ie nt y ie lds in y oung t ops of f OUY w oody specie:; w i t h five prlm.i ,tgs in a y ea r (1985). "},{"text":" ) fanns in several countries of t.ropical Africa have become an increasingly in1.portant s ub-systeITl of traditional farming systems. Encompassing t h e imme diate area surrounding t h e household, they contain multi-use plan t s pecies -field c r ops, trees and other woody s p ecies -and s m all livestock , a U of whic h play strateg ic nutritional r o les. "},{"text":"FallowFigm'e 4 , Figm'e 4, Sc he m at ic diagrcul1 oj co mpoundJarm s in ,'elatio n to a ssoeicltedfield s in t,'adi tional Janning sJls te ms oJOre humid l)'opics oj WestAft'iea. (Sow'ce: FAO /984.)     "},{"text":" tiwr(' Ill<ly not b . . . . . enough so up that co ntains fi s h , mea l. o r anol h er protcin so urcf' , anel ill(' r hild rc n get o nl y Lilt\" starc h y load !>., ~ 1 ajo r fin din g~ or a 198•1-/85 : o:ocio-l'co no mi c \"i Un ' l' ~ of 386 o ut patil'llL\"i of th l\" clinic at Ogbomosho in cluded: • TIll\" IllOs t n'CUIT(' 111 malnutri ti on fa c lor was \",Iwl her the.: c hild was being c; m:d lo r by his o r hn mo tiwr. I (' (\"<Ircd for b~ :1 g uardi:lIl. lh (' c ha ncl's ofma l11lllrili o n \\\\'l'IT hig her. • Young g i rl ~ lil c . "},{"text":" . "},{"text":" . "},{"text":" . "},{"text":" . "},{"text":" d great!'!\" clt-grl'l's of malnut r iti o n t ha n boys. • \\\\'o l11 c n w ho W(Ti.' r:umcrs 10S1 m o rt ' children two o ut or ('vcry nin e bo rn . W0 I11('11 with occ upations o tlll'r lha n ra nning two oul or tTl'!\"\\ len: 60 11 \" of \\\\'o nw n fanners IOSl Because of se\"io ll s pl'otein Ina/nutrition (1I110Ug m.tl ll)! Af\"icall c lri/d,'e u , $i'oybean P\" Oduc lion a nd uti/iz ation is ,'eceiv illg ',\"o/'e aUentioll twd lI c l io ll , especitdljlfrom wo m e n in \"tH'u/tll'etls . "},{"text":" Fig w 'e 5. H istogra m s howing p\" ices at Ogbomosho. Nigeria 0'1 F\" idaYI Sepl.embe ,• 20 11985 compa,red w it h costs 0/ alte\"native/oods w ith a p\"otein v alue eq uiv alent to thai of a daily intake of 120 g\"ams of w hole soybeans (40. 4 g protein), "},{"text":"S{' C the c ro p al dinc rcl1l sta ges: 2 ) illustratcd pamphltt pn'pa red in Llw loca l lang uage a nd g iven LO pl.'o plt• in Lh t art.•a; and (3) soyb ea n sted sold to I~\\nners at a redu ced price, A lllt.'lllblT of the cli ni c stall' \\\\,orh•d nearl y full time to explain the c ultura l prac ti ces n('ccssa r y to g row soybca ns, A 1l11l1lbtT of' rarl1l crs (bot h mcn and wOllle n ) art now grow ing th e c rup a nd soy b ea ns arc so ld in local On-Farm Research with Early-Maturing Green Maize in Southwestern Nigeria I n southwestern Nigeria, as well as in many other parts of Africa, people face a food shortage at the beginning of the rainy season. The food shortage occurs because fo various reasons insufficient supplies are carried over from the previous season o fungi insects and other pests have devastated the food reserves. Maize-normally the firs crop which can be harvested -reduces the length and severity of this shortage when it i harvested green and eaten off the cob as roasted or boiled ears. Further reduction could be achieved by farm.er adoption of earlier maturing maize varieties. "},{"text":" ('a I' S ~la rke[ah l t' cars i\\ 1:l1\"ketable (°0 1 \" aItH'/l'a r Cro,~ bendit Itvels of resea rcher-a pplied fen iliz(T. Fou fa rmers completed the trials, T he lOta ln umbe of cars ha rves ted was greater for T Z ES R-\\\\ whi ch is a reflec ti on of th e bCLLcr pla nt sta nd achi eved wit h IITA-slI ppli cd seed (T a ble 6) Beca use of 1<' 1 Ie!' ma turi ty. th e loca l va riety had la rge r cars an d thus a hjgher percentage o ma rk cta b lC' ca rs . Fert ili ze r increased t h Ilumber a nd pcrcentagt' of ma rkctabll' ca rs. "},{"text":"• TIlt' /lIIf/i(l1 bllngrl il/tludrs OIl[J' IhoSt' (Om whirlt diffir L!./' /f((l(IIII'III. I 'alllt'f (lfr II/ . \\,i.1!.rmlll \\ •aim/lta. "},{"text":"Figw'e 6 , Figw'e 6, Fluctuations in g,'een nwize prices JromJltne through September' 1985 at the Ijaiye m a,'ket nea.,' l badan. Nige,.,'a , Availabib:tyoJ g,oeell maize is Iim.;t.ed be/moe June or aJte,' Septe m ber, Price ( kobo/ kg I "},{"text":" Tab le 7. Tt'etltm.e nts i mposed in a long-te rm. d eforesta tio n and land-use p roject in so uthernNigeria.    "},{"text":"Figure 7 . Figure 7. La\"d clearing method and soil bulk del1sity o,te year after clearing . (Each dattun poin t is all average of eigh t nl€as'Ure m e nts exceptfor ,nechanical clearjPlg w he re 16 points were considered.) "},{"text":"38 Thl' low ('\\'a potranspil'tllion in fores ted cOlllrol is dut.' to the rac t that no trees were grow n in the fo rcstcd Iys imc[cr. he nce the low transpiration. This situat ion wi ll cha ngl' wilh the estab lishrn enl a nd growth of' young seed lings already takin g rOOL Among dinc.'l'ent land use tre<11 -1l1l'nts. the ma ximum c\\'apotl'a nspi ration rate w as hig her in improvt::c1 rores try a nd ri ce th a n in otht.')' trea tmCnLS.\\\\'a L er ru noff and soil crosioll \\'aricd among diffcn'm iandusc Il'ea Lml'Il(S. As ex pecled, the least rUTl olf a nd ('I'osioTl W{' I'(' o bserved in ron . . ' S L cd comrol (T abll' 9 ). Bot h runoff and eros ion we re low und er trad itiona l 1~lrmin g and cassava but rel a ti vel y hi gh under peren ni al crops (e.g. oil pa lm. impro\\'l'd rores try, coconuts, and plalllai n) because of's low g rowth ratl' a nd low canopy cover .G rowth or ri ce, ma izt•. plantai n , pastures, and tn.:l• crops was influenced by dcf'0I'cs t3tioninduced cha nges in soil propl.Tties. u pla nd ricc growlh an d yields Wl.TC superior in windrows \", h . . . . 'l'c dri ed wood s \\\\'('I't.' b urn ed afte r clea r ing. Varia tions in ri cc g ra in a nd Slraw yields a lllong fo ur va ri nies arc shown in Table10. TIl{' mai ze crop (TSESR ) showl'd ('x lremcly poor growth a nd rai led to produce any signifi ca nt grai n yield beca use or poor soil fcrti lit y. no rertil iz('1' a pplication . a nd high so il acidit y.Pri nci pa l coll aborator an d fin ancial sup-porteI' in this long-tl' rm projccl is the Uniled Natiolls U ni vers ity. The Okolllu Oi l Palm Com pan y Ltd. provicl ccilhc land. "},{"text":"Fig u re 8 . Fig u re 8. Laud clearing m e thod and i\"filtral.;on ,'ate o ne yea r afle ,' cleCl,.;ng, (Eaclr dtJtum. po;\"t ;s (lI' a v e t'age of 16 nle llS1U'e n1.en l s ; lhe is is lhe stelldy-slllie j\"jiltn,lio ll rille.) Inf iltration rate (em Ihr) 200 \" -----------------------------------------, "},{"text":"S cientists continu e to sear c h for lan d mana g ement systems that cause the least damage [0 t h e e nvironDlen t and make it possible to inte nsivel y c ultivate tropical soils without the trad.itional long bush fall ow p e ri ods. One of many phases of this sear c h in volves an assessment of two leg umes as live mulch g r o und cover s -centro ( Ce ntroselna pubesc€n s ) a nd psopho (Psoplt orca rpTts palustris ).Research on lhe liSt' of t ill\" tropical kgulllt's as li vl' ll1ulchc!) h a~ shown that wtl'd interference w ith crop prams ca n be minimi zed. and, iC so il moisture is not limiting. crop yields in th e li\\'(\" The live ttl-ufelr cove l' PfopllOrrmJms /Xz/lIJlrif co ntrols weed s llnd cO lltl';blltes nitrogen 1 .0 th e soil, ,-esliitinJ: iu hig h maize Jlie lds. No nit.rogen w as applie d in th isfield t rial. mulch sys tL'm are sup er ior LO thoilc in conv(\" ntiollal ur nO-lillagt• sys tt:ms al low kvt:ls "},{"text":"Fig Fig m 'e 9 (Left). Eff ect of p soplro leg ume 0 11 nitrogen contributiOll to a maize c rop in (I live milici, mmwgemen/. system ; Figw'e 9 (riglrt). Effect of live mu/c lres (Iud til/Clge sJlstems 011 w eed seed s ill the soil afte,.fo lll•Jlew •s of cO lltinuo us c \"opping III IITA .Nit rogen cont ribution by live mulch (kg/ ho) 50 "},{"text":" LS D (5°'0) /or (olllpn rillg ground (Ol'(r IIIfOrlS = O.9101l s . "},{"text":" mechanized fanning in the humid and sub-humid tropics of Africa is fraught with fa ilure mainly because of rapid soi l erosion and degradation, despite the use of c onventional soil conservation measures. Smallholder farrners in t h ese regions, however, do not face such proble ms because they normally clear small areas of land manually (one to two hectares ), and the land is cropped for two or three years and then returned to forest fallow . A rapid increase in the pressure on land in recent years has led many researchers and p lanners to seek effecti ve wa ys and means for land clearing and contin u ous cultivation. "},{"text":" Uppe~' ph oto: The flail m .owe'\" produced the m ost sa tisjaclo'J' \"e~;ults ; lo w er photo : a thick. even. cov e ,' of ntucwra p\" o v ided a good ;11 1;(11 m.lIlc hfor no-till pla\"ted m .u;ze. \" False Decapitation\" of Plantain: an Improved Field Technique for Rapid Multiplication P rodu ction of p lantai n -a major carboh ydra t e s taple food in the w e tte r pa r ts o f t h e humid t r o pics -has not k ept p ace with d e mand from a fas t g r o wing u rban p o pulatio n and p r ices are ris ing. Shortage of p lanting ma te rial sta n d s o u t as a m. aj o r con straint to e xpa n si o n o f the cro p . "},{"text":" or t ill' many tec hn iques c!(,q']opc-d to incr<-3sc liw multiplication rate, tht' two IllOSI comlllo n an-cit'cap iull ion with dCSlruc Li on or the a pica l I11cri sl t'111 a nd ill vitro mu lt ip lica ti on with l11(\"ri slclll ti ss ue . The latter g in's a hi g h multipli cation rate but. it is loo sop histica tcd for most r.-.rml'l\"s of d eveloping coun tri es in which piantHin is important. The rormcr has b('cn uSl'd slI CCt'ssfully. but this u:chn iquc des troys the p hoLOs)'nthe Li c organs at the time of apica l do minance suppress ion. This ca uses the new buds that sprou t to produ c j' Ill'\\\\' suckers lhal depe nd so lely o n food reservl's of thl' P,H('l1t p lant for cll'\\\"(•lo p nll' n t. CCII IM'CjUt'lllly. sur kn dt' \\'elo pmcilt is s lo\\\\' and th e .; uckers produced a rc 1101 as IIU ITU,TOUS <-lI1d \\'igorolls as dl'sir('d . T o O\\'{' I'COJn C tht, 'i hort co mings of thi s l('C hniqu(', scieillists han' clt-visl'd a mc thod fo r (kS ll'O~ ing thl' a pica l I1wri stem a nd l' limin ating ap ical domina nce wit hout des tro~'iJl g th e phn tos yntllt'li c organ!' !. ' Th ey (':-dl it \"fa b\", decapitatio n.\" \\ Vi ll) Ihi ~ ll'c hn iqw' whi ch is n •co l1lnl1.'ndl'd for sma ll fa l'll1lTs specia li zing in \",ucker produClio n. a sma ll cut is madc Il ea l' til(' g round in Ill(' base of 111(' moll1('r p ia III r Figure 10 , .\\ knife or similar instrum cnt is instrl('d throug h it dcep enoug h to destro y lhe mrris l(•l1l. Exccp, for a SIl1:11l holc, the PS('ucJos tt ll1 a nd It'an' ,!; are lIninjur('d a nd continue 10 fU lict ion fo r abo ut Ihn:e mOlllhs after thl' ope ra Li o n. The Ill' W lC'c hniqu C' that dcstroys Ih (' meristem but not th e folia gt' product•s signifi ean ll y mOI'l' sturcl ysucklTs (han lilC'oldcl' tcc hniqu(, in +6 whi c h the foliage was 1'l'l1lo\\'{'d (T ab le 12). "},{"text":" mrrulrm amI folia.!.!, dt,l/m.)'td. B : wmt os . 1 but 11\"/111 mounding loil, e: aplml IntT;slnn dlltro..w/ huJfoliagr rrlmntJ. IJ : ,\\(//Ilt /1.1 r h'ltwi,It /I/o /wifing ,lfjil. "},{"text":" Figw-e 10. A new tec hnique thill d es IYo),S I.he men's te m but not lh eJolillge. ll p,-oduces mOl\"e sl,up•dy plant\";,, $ucke,•s than the aide,• teclnrjque'-n w hic h t,heJoliage w as re m oved. The new method;s especia lly su ited/or-s m all fann e ,•s specializing in s u c k e r p,•o dllc tion . "},{"text":" R ecen tl y Lhey have received 1110rc a ttention by na ti ona l resea rc h p rograms tha n in lhe pas t, 3Jld improve m ents a rc sta rling LO be m ade in trad itio na l rarm va ri e ti es a nd p rod uc ti o n techno logies. Du r i ng 1985. seicn lis ts in l he G ra in Legume I mprovcm cn t Progra III conti nu C'dLO d evclo p stablc , hig h-yielding lines suitable (or the dirrerent eco logies a nd cro pping systems wi th lilt' p rinc ipa l a im of improving the in com e a nd nutritio n of 1:1 1'11'1 fa mili es. The y have devrloped va ri eti es w hi c h m a ke cO\\v pcas less risky lor c ulti va ti on b y small fa rmers. ~ lost Afri can farmers . for exa mpl e, consid er cowpcas a hig h risk crop because of pest and d isease pro blrms. Attenlion co nlinu ed to be foc used o n new insec t, disease, a nd d ro uglll resista nt va ri e ti es. But th e deve lopment of ca rl y maturing cowpea va ri e ties, w hi c h is o ne of the droug ht esca pe mecha nisms. a Iso rf'ceived a hig h priori L y during the year as anot her strategy fo r red uci ng risk of c rop fa ilun: . Nnv soyb ea n lin es with n'ce nodulatio n a nd good seed lo ngevit y also show pro m ise for s llla ll farm cu lti vatio n . These va ri e ti es d o not need rhi zo bium inocu lulll o r ni trogen fe nili zer and seed s can be sto red under am bi en t co nditio ns. "},{"text":" Scientists rrom ma ny countries auended the Tropical Soybean Works ho p o n Resea rch . Prod uction and U tilization held a t IlT A in O ctober 1985. One o r the signi fi cant resu Its or a World Cowp ea Conference a t the institute the previous November was the publi ca tion or Lhe proceedings in a book elltitled , Cow/Jea Research. Production and Utilizatio n. Proof of th e worldwide interest in the conference sponsored jointly by IITA a nd Bea n/Cowpea CRSP was the number of scientists, ex tension personn el, governm ent o Hlc ia ls and olhers who attended -203 persons representing 34 countri es in Afi'ica , Asia, North and Soulh America. a nd Europe. The training p\"ogra',n received special auention during the yea r, with soybea n/cowpea produ ction lraining in creasing four-fo ld. I n the pas t, o n(, training course was o ncred eac h yea r a t [I TA but no regional courses. During 1985 , two courses were held a t ITTA headquarters and two o (fsite in so uth ea~t Asia and Latin America. In addition a special intensive training course sel;cs was initiated for 12 national scienlists from II countries during periods ranging from one to three months. Degree-re lated tra ining was a lso expand ed , and 12 g radu ate sLUd enLS from nin e African countries participated in g rain legume research ror theses required by thei r uni versi ties. "},{"text":" [n the follo w ing pages , notable r es earch hig hlight s during the y e a,-are briefly d escrib e d . More c01nple te info nnation on the s e topics and those 1ne ntioned in this Executive Summary can be obtaine d by r equesting the Annual R eport of the Grain L eglune Jrnpro velne ntProgram.    "},{"text":" SciCllrisL'i in Burkina Faso arc \"ngagcd in d eveloping imp ro\\'('d cow pc-a var ieties ror droug ht-p rone regions. Las t Y('ar 111{'Y [es lcd LI1I\"(,(, new varil' Li es across a w ick ra nge of environm e llts in co ltabora ti o n w ith nali o "},{"text":"• Follr l(wAs (If Iff II/Of/ling. "},{"text":"54 Performance and Prospects of Dual Purpose Cowpeas for West African Farmers I n the Sudan Savanna and Sahel ecologies of West Afri c a , fodder obtained frolll cowpeas is as important to man y farmers as the grain. Nearly every househ old has domestic animals a n d a severe shortage of feed is the normal situation in the dry season. "},{"text":" t/ ha o f' g ra in a nd 5.2 L l ha o rfodd eJ\" in a rcas w hi c h receivc-d about 850 m m o f a nn ua l rai n fa ll (K adawa. fo r examp l{' ) to 1.0 L l ha of' g ra in a nd 2.6 tfha of foclcler in d ri er zo ncs ( \\ Ia ll a m ~I a du r i , ror exa m p le ) w ith a pproxima tely 400 mill o f ra infa ll. Co rres po nding yields fo r th is var ielY in Niallll'Y (260 I11 Ill ra inra ll ) were 1.0 tl ha fo r g ra in an d 0.8 l/ ha ro r rorogc. "},{"text":" K{m o~ Nige\"ia ; in addition to th e fodde ,', ar e du{\" pW'p o s e cowp ea produced afai,' g ,•ain y ie ld.we re incl ud ed in Lhe tria ls bo th in N igeri a and :\\,igeJ\" R epublic. A t Sam a ru .~i g cri a, th va ric ti es werc p la Jll ed o nce wee kl y sta rti ng fro m J ul y 29 to A ugust 12, b u t on ly o n p la nt ing wa s don e in Nia m ey, N iger R cpu b ljc Thnc was a prog ress ive d ro p in bo th gra in a nd roragc yields ora lli cst va r ieti cs w ith eac h wee d ela y in p la nt ing. The la rgest reduc ti o n wa suffered b y the ca rl y-m a tu ri ng va ri £'t y IT 82 E 60, b ut TVx 4659-0 3 E consistcnt ly gave ove r ..J. l/h a foci cit:r yi eld for a ll t hrce pl a nting d a tes I I a lso gave th e hig hest g ra in yield ( 1.6 L/h a a nd a mod est 2 .1 t/ha ro rage yield in N ia me (T able 15). "},{"text":" Cowpea lines Resistant to New Strains of Two Common VirusesA rnong the several viruses known to infect cowpeas in Africa, the aphid-borne mosaic virus (CAhMV) ranks as th e m ost important in all a r eas where farm e r s grow the crop. In second place is the beetle-transmitted cowpea ye llow tTIosaic virus (CYMV).I n SUITCYS fol' cowpea viruses in Nigeria o\\'er the past two ),C'a rs. isola tes of CAb.\\ IV W(TC obtained w h ic h ex hibited consid erable pathogen ic ,\"ari<lli o n on the basis of th ei r symptoms Iype and s{'\\'{'rit y) on 50111(' selected lest plants and cow pc:a \\'a ri cLi cs slich as I fc Brown and IT28E-I O. A ncw isolatl' (\" IT-16\") S(,(, 1115 to represc nt a different slntin arCAb .\\IV than the \" Onne\" isolate Ll sed so far in r(\"si s Lan C (~ sC ITcning. In 1985, a new strain o r C Y~1 V ( CY ~I V-K') was iciclllilicci. The iso latl' reprcsellling thi s stra in was round in a f~u n1('r' s fi eld in Nigeria's Kano Sta te. In iniLia l l es l s ~ it inrected the cowpea lit1f' IT 82E-IO w h ich was found to be imlllune to CYMV) th e standard iso late used so far for rl'sista nce sc reening. Because o r th l' pathogc.: ni c va riation or bot h C Ab:\\ IV and C YMV , sc iclllists arc updatin g ava ilable inrol'm3tion o n resista nce to these strains a nd sc reenin g se \\'C ra l adva nced cowpea breeding lin es ror resista nce to the new isola tcs. They tcsted I i6 breedi ng li nes \" 'ith CAb :\\ rv and 59 cowlea lin es with CYI\\lIV. One-weeko ld seed lings WtTt' in oc ulated o n th l' primary leaves with a seco nd inocu la tion Linee d ays latcr to avoid a ny escapes, The piallls were scored ror ITac ti o n 10,20, a nd 30 da ys artel' th e second inoc ulat ion and g rad ed on a sca le o r I (no sy mpto ms) to 5 (severe symptoms) , Evaluation o f' th t' sy mptoms in the 176 breed ing lin es inocuiaH. 'd wi th lht' iso latt,S \" Onnc\" and\" IT-1 6\" o f' CAb :\\ll V showed lhal th e adva nccd b rccd ing lin es IT 82E-8S9, IT 56 82E-60 a nd IT 82D-885 a re hig hl y r csista lll 10 "},{"text":"3 (Q be rcsislalll to th e standard isola tcs o r C Ab~I\\ ' a nd C Y~IV are slI scq Jli b le to th{' new iso la tcs. Howeve r) th e majorit y or lin es used so rar in screening at I ITA w hi ch ha\\'l' I'esista nc(' to th e stallda rd iso latt's of the \\'ir usl's aL'io possess resistance L O thl' new isolal(•s. )1c\\'c nhd css. potential brccd ing pa ren ts a rc being screened fo r resista nce to all known types o Clhe viruses. Pm•ticles of cowpea yellow m osaic vil'us magnified JI 2,000 times. 110 .~),/IIf!'olII l . 5 = $ltV'rt .fY1II/1/{JI1U.Table 17. R eaction of selected cowpea lines to t wo isolates of yellow mosaic virus (C YM V) i Nigeria. Lef t, a la,,• see de d cOUJp e Cl line.(eNe')'• 252.1£) w it.\" co m.b;ne d r es is ta nce t.o p Oly v i r ll s co mplex an.d cowp ea s eve ,•e m os aic v i r u s ; ,•ig ht, a v irlls s us cepl.ible 'l Hl yiety VITA 7. Virus Resistant Cowpeas for latin America A ltho u g h a majority of Latin Ame ric ans prefer dr y b e ans , c owpeas play an impo r tan t r o le b y p r oviding ine xpen s ive vegetable protein. In n orthe a s tern Braz il, fo r e xample , a ve r a ge annua l p e r capita cons u mption has reac h ed 40 kg. Furthe rmore, from a production standpoint, c owpeas in a trop ica l lowland ecolog y have s e veral advantages over dry b eans -fewe r dise ases and insect p e sts and g r eate r toleran ce to drou g ht, wate r logging, infert i1 e soils, and a c id stress . "},{"text":" eNC 043'ta w hil e-seed va rie ty released in 1985 carries the gene for immu ni ty to CSMV. Il was s('lcclcd in Braz il fi•om a populat ion sen l li'o m I ITA 's headquarters in N igeria a nd has now bee n n:col11m encicd by se vera l sta tes in lha t co umry. BR I-POly -a ta n-seed ed va ri ety carri es Ii 'ld-Irvel resista nce to the pOlyvirus 58 co mplex a nd was released in Brazil In 1984. (l ITA 's gc rmp lasm line TVu 4 10 was th e do nor o f the res istance genes. ) Bo th va n etl es we re se nt by the II TA / EMB RA PA La un Ameri ca n Regiona l Legume Progra m in 1985 to a pproxima tel y 20 sit c.\"S ou tsid e of Braz il. Severa l lan-seeded breed ing lines have now been deve loped Lha t co mbine resista nce to both viruses. CNCx 187-22 0 -2, tes ted in a n Ad va nced Yield T ria l in 1985 , d emonstra ted good yie ld pOtent ia l (T ab le 18). Petfonna nceof' a no th e r tan-seed ed line wi t h com b in ed res istan ce -C NCx 252-1 Eis show n in T a b le 19. Bot h of th ese lines a rc now being used as parenta l ma teria l in the c ross ing progra m. Beca use ma ll Y cO ll nl ries prefer la rge sct.'d va ric•tics, CNCx 187-22 0 -2 is a pa rtic u la rl y useful par{'nl dUl' to il s co mbinl'd \\'Irus n.'s istan ce and acceptable s(:('d size, Out of 17 impro\\'cd cow pea varic tics rekascd b y various stalcs in Brazi l sinet' 1981, ~e V en a r c direc tl y from II TA gcrmpl a;;;m a nd four from crOSSl'S involving IITA gl\"rmpla'l lll, Althou g h it is no t possible at this lime to d oc ume n t the total arca occ upied b y thl' new Table / 8, Pe rformance of cowpea line CNCx 187-22D-2with v ir-us resistance in Advanced Trials at Goiania and Serra Talhada~ Brazil ( 1985), Cowpl'a lin eS C;\\'Cx 187-22 D-2 'ar itties deri ved din:ctl y (i'o m I rTf\\ gc rmplasm, f:: u'mt'l'S in many Brazilian sla teS han' pl a nt td th elll, Fo r exa mpl e, at 1(,lIsI6.000 hec tares of EPACE 1 arl' now g rown in Ceara Sta\\('l and it is popular also in Pi a ui and Ri o Grande d o NOrle. EP,\\ CE 6 has shown promise in illlerc rop ping with sugar ca ne in Ceara Slat a nd with colt on in Paraiha, and 1\\lanaus lIigllb' resislrlll/, 5 = /\" 0' SllsfI'/Jlihl,.' s(orts from i1lo(lI/a/l'd /ria!, "},{"text":" lIigl/{J' \".sis/an/, 5 ... L\"~J' msu/ll ib/,; S(l) l •tJjrl) /11 i\" ow!(lIt'(J lri(ll,    ly grown in tlw humid nonh in Ih (' sla lrs of Am azonas. Rod olli ,,\\. Acre . and Ro ra ima. CNC O•~34 .m el BR I-POl Y arc being mullip lied in seve ra l Slat cs bcca usc' of their resis tan cc to \\•i ru s diseases. A w hite-seeded cowpea v ariety (GNG 0434), w hich c urries the genefor inU111fuity to co w pea seve ,'e 'J1osaic Vi,.\"S, w as \"e le ased in Brazil in 1985. It is being multipliedfo r ja1•nter use. 60 Improved Aphid Resistant Cowpeas A phids ( Aphis c 1'acc' l:vo'ra ), a major problem in all cowpea growing countries, not only cause direct datnage by feeding on the plants but a l so transmit virus diseases. To help counteract this production constraint witho u t resorting to repeated insecticid e sprays, UTA scientists identified several sources of aphid resistance. Then, through a systetnatic breeding progratn over the past four years, they developed itnproved varieties which con1.bine aphid r esistance with multiple disease resistance and hi gh yield potential. These were first evaluated for yield in 1984 and retested in 1985. Specific sprays arc so metim cs need ed to cOll trol ap hi d s fi nl y. panicub rl Y:1 t th e s(,l\"dlin gstag(' in dr~' n •gio n:-i . \\Vi lll a phid rf'Sist3m varic t ies. far m ers co ul d rcdll c(' th l' ll llmbt.T or sp rays. H O\\\\'('\\T L dl('Y may slill h~n' 10 lise in s('clicid cs 10 cO lllro l m hel' insc(L'i durin g lilt' g ro wing seaso n. TIlt' ge neral p('rfo rm ~III C:(' of' si;.; \\'ari tl ics during 1985::'1 t four l oc::ll i on~ in N ig eria and o n(' in Burki na Faso is shown in \"'r ab le 20. In lhese Illultilocatiunal It.'SIS. IT 83S-7-1-2-11 and rr 83S-728-5 had lhe two hig h es l ov('I'(l 11 Illean yidds, They consislclll ly pnfo n11t.'d wdl at ,Ill loca li ons wilh good res istan ce to aphids, Seeds of'lh est t wo lin es han' bt'l'!l mul tip li ed and will hi\" d istribut cd L O va ri olls na tion al prog ra ms In 1986 ill : 111 illl t.' rn a lio nallri a l. "},{"text":"1 Dihiro e soybean is a n ewly introduced crop in Rwanda, its c ul tivation is spreading fast as a complementary g rain legume to beans and p eas. Trials conducted by scientists in t h e ISAR / llTA farming systems research project during t h e past two year s indicate t hat it has hi g h potential in marg ina l areas s u ch as B u gesera and G isaka whe r e t h e bean c r op faces several constra ints, including low ra infall (350-400 mm p e r season ), poor soils (particularly o n th e plateau ), and serious disease problems.But th e soybea n a lso faces produc ti o n problems in Rwanda. includin g poor nod ul ation Wilh na lin. ' rhizobi um , rapid loss of sercl viab ilit y wh(,11 sto red in a warm . humid environlllenl. and poor germi nation under inadequalc rainfa ll at the linw o f sowi ng or during a dry ~pd l o f 7 to 10 days imJ1l ediately artl.T sowing.To tackle th ese en vironmellla l co nst rai nt s.seitn USLS asstJ1lbkd a wid e r~lnge of ge ne li e a lly diverse soybean genot~'Pt \" li'l)J1l di fle-!'ell t 'ou !'Ces for It• ... lillg 011 the pour platl'au soils, :\\ lorC' than 70 lines \\\\'l'I'l' e\\•;t!ua ll,d a t K agasa during 1983 8'-) ull(kr J1lultiplr SU'('ss COIlditions slich as l(1w ((.' rti lity. unp redictable dry l -i llt'lis. and disl'il 'l(' pn•ssun: . :\\ 10 51 3(b ptabk lillt • ... :.dlTll•d from these initial trials \\\\' ( ' 1'( ' a(h'ancl'd tn mult il ocational tt,~t ... at diilelTIll agro-{'cologica l /'()I1l'S of Llll' Burgcst: ra -Gisaka-:\\ Iigongo region, Gra in yield s ol' six promising nll' ly-m <llllri ng lillt's :ll \\WO Silt'S arc shown in Tabk 21. Yields at Dihi ro. w hich represents the Bugt's zonl' charactl'l\"ized by 10\\\\ \"ai nfa ll a nd poor soil..,. \\\\TH' general ly low. SO) hea n lin l' L2-3 gav~' dw highest yidd of 1125 kg/ ha followl'd by L2-7 with a yield 01'775 kg / h ~l. At K ibullgo in till' Buju ZOIlt' wi th I'l'iativdy n. 'l'tik \"oits ~lI1d hl' lI lT rain fall. ~ idds WeI'(' co n s idr rah l ~ hig ht'r _ Based on ml'a11 yil' kb. a ll th t: s n~' bt'an n ll-irlil's rxcl'p t Bnln tol1 yield l'd marl' th an 1;000 kg/ ha, F:lrmcrs can pla ul lhese \" ~I r1 y-m :ll urill g li11 l's duri ng both Sl'asons. 62 Days to maturit y alld gra in yields o f six m edium-I o-Ia tt' ma turin g soy b l~a n lincs whi c h gave consislt'lllly good yields O\\' IT two yea rs are !' i hown in Tabl~' 22. TIl(' llll'Cliul11malUring lirll's a1'(' w(' 11 adaptcd to drought s tl'('SS a nd low so il ferti lity, Based o n ot her lri ~d s . lh (' longd uralio n lilll's showed a pOlcll ti n\\ fo r usc as a grtt' n manure cover and foclclcl' cro p , Furthermo re , soybeans perfo rm ed wel l in mixl'd cropping S ~'S h' m s , On-fa rm \\'arie ta J ('valuatioll 0(' soyb\"an ~ p resen tl y 1IIlcit-rwi.\\ y will icklllif) a pp ropri a l(' a nd po ten tia ll y prod uct ivl' \\'ariru{'s !()T' di m. : rCIll agro-('coiogicil l zones. TG\" 297-.35r TG \" 5.33-65c TG\" 536-1()(k~ TG\" 122-02D Yit'lel kg h, "},{"text":"Figw Figw'e J J.SOJlbem. v an'elal yield ,.espOJlse~• to c/w Jlges be t ween ,.ow spaci\"gs, "},{"text":" \", \" ,f,~''t-~ . .... \"'-' -,;; '-'rl'\"\"'''''\";:,, (;'-8. y..~~:i~\",~.--~., ,..., '\"\"''::l\\.~-~ • . -.., ... ...... . ~.--. • ~. ~-~....:~~~J f!. . . . ~ ~ ;. ~';!Y\"'\\\":~~~:\"\"'-i\\~?~~:~ f ~~. , .-\"~5~~r~;~~;~ ~. ,.., ... . ~.,~~-t~. ~,r.-lot.' ..;$';7 ...... ~ ~, . . . . .. )>-..... ;;. ~ .,.,. .. -~_. ,c.:: ~~ 'j:;.' \"'<' .l. _. -....... _~ ... -~\" .l :.~:.' ;.::... . }--. , ' .\"'!o--i .... . ~<~ . ~ . . ~.~, ':~.!._ ->-.\":': ~: . ~: .. '~..;~. ~~\" -Wtw 1Q'/~\"\". -. ~ . -.... ........ -~\" . ' . . ~ .... . , ,:. '~. j--:-' -':~~~.'-~ -~~~. '-' .. ~~-. . -'--..,:-.. ~.-,\\,~\"\" , . ..;::. . ... ~ -. -. ,::'f,. . ; , . .•• t } •. ''''; :Af,. ),..-~\"-\\~~, ...... , . i~. _ -.\" ~ .... . .-, .. ~ ..... \"\"\" . . . . . ,~-, :. '1-j . . -:. .. ~ .. . . . . ~ . ,~-\",--.~ __ -_ ...... K ..... \". 'It.16:. t-Joi . .,.;~. ~ ,. ~'\" ~ ... ~~\" ~~'~-'-$: :J!Y, . .. ~.,.,.,.. .... -..:.~. • > -•• ~~-.... '---. --~-..L:': __ ~ . So) ,beulls planted by ajanJl e r twd hisfa mily Wider hig h population i\" all i nte l•c r op sitltatio'l . Testing Tropically Adapted Soybeans for Resistance to Soybean Mosaic Virus S oybean mosaic virus (SMV) is found in many parts of the world and can cause serious yield losses when it is epidemic. So far, in Nigeria and other areas of West and Central Africa, SMV becomes a serious problem only in the dry season but because the disease is often see d-borne it can spread from one s e ason to the next. Infected plants IDay be stunted and less productive, leaves tend to be narrower, leaf margins turn down, and blades become severely ruffled along the edge of the main veins. Soybean Lin es resistant to SMV we re tes ted in 1985 rOf yield and agrono mic characters) and lin es with tropi cal adap ta ti on, hig h yie ld , and desira ble ag ro nomic c h a racter isti cs n ow in corpo ra te S MV resistance (T a ble 23) . T he work represents a cooperativc eOo n bc t wcen the soybean breeders and virologists a t IlTA and with the I ntcrnaLional Soybean Cenler (I NTSOY) in lhe Uniled Slales. "},{"text":"* Sltntlrrillg ralillg: J = 110 IXllls sltollrml: 2 = < 25°{. slll/llered,' 3= 25-5(J' ~,,''' = .50-75°/,,: 5= > 75\" 0 J/wflrr,d . • * Lodgillg mli,,:: I = all plollls f(l'rl,' 2=soll1r /1101115 lealling or lodged: 3= 1II0SI/I/(lIIls leaning. l 'OIlU lodgrd, ,,= most /11(11115 forlgnl: :) = alll/hllllS IOtlged, *** Sf!)'htfllllllosaic virw ralings ( I 5smle) : J == //0 Sj'mIJlo/llS, 5 = Jeu(!re J)'/111110/llS, Tab le 23. M ean y ield and ag rono m.ic c haracteristics o/promising soybean lines w ith resistance to soybean mosaic virus (SMV) grown at Mok w a J Nige ria (1985). "},{"text":" e (SMV-I O) w hi c h is less viru lent , thoug h typica l of th e virus fo und in the fi eld_ So far , lines resistan t to \" Micro A I ) arc gl'nt.Ta ll y resistant to commOIl fo rms of th e virus. Lines sho wi ng no sy mpt o ms of S MV in lhe g reenho use arc t('sted to a suscepti ble \\' <:lI'iet)' as \\\\'('11 as by sl'I'o logicalmcans. Ifbolh back teslS a re negati ve, it is ass um ed th al th e lin e is resistant to S M Vas it occurs in N igeria .o rne o r t he li l1c:. 'S shown in Table23 donOt have ad equatt.• resistan ce to shallcring a nd lodgin g, and th<:: y have nOt ye t been tested for their rea c ti o n to o ther diseases. A ll lhc lines lisLl:d in till' tab le re prese nt ca rl y-maturing I ypl•S. T hey w ill be crossed wit h o th er tro pi ca ll y ad ap ted lin es to b ring in o th er res ista nce if necessa ry a nd to inco rpo ra te SMV resista nce into li nes in otht.'!' mat u rit y g rollps. \\' Vo rk has bC'gu n to I t.'S I o th er pop ulalio ns o r crosses bc tw('ell adapt ed pa rents a nd S~I V rcs ista11l lines from Zim babwe and th e U .S. Maize Research Program R ecogni z ing the need LO s tre ng th ell resea rc h fo r in crc;1sccimai z(' prod uc ti o n in An-iea , avoid dup li ca ti o n or (•(fo n s, a nd improve coordin a ti o n or the intern at io na l lcsting p rograms. I IT A ancl C I:\\ I ~I YT eSlab lishecl a jo in l program for Afi'iea in 1985. The m ost sig nifi cant und (,rta kin g or this progra m during tlw yea r was the establ ishm en t or the III iel -3 1 ti ru ck germ plasm ckvd opllll'1lI site ill coop . . :ra t io n \",i th 1 he U ni ve rsi t y o f Z i III ba bwc. Ill itiall y, two SCiCllIis l S -a brecder and a ll l'lI to mo logist -WlTl' posted in that co ulltry and other sc ientists wi ll 1)(\" a ssig ned to th e proj ec t hu e I'. Its majo r aim is LO devciop stab l\", hig h yielding. a nd ciiscasc-J'esislarll maize gcrmplasl11 ada ptcd to t.he mici-a hiLUd e eco logy in .\\ f'ri ca. I n add ilion lO H a ra rC. Zi rn ba bwc. t1w jo i n l p rogra m o pera t~•s prcsen tl y in two o ther majo r Sill'S: Ibacla n , Nige ri a and Ouagado ugo u 1 Burkina Faso. 'The lhree rl'p rl'sellt a ll the impOn a nl l'Co logir s where maize is g row n in Arri ca except hi g h a It ilLld c -over 1800 m above Sl'a k'vc l. Sc ie ntists a t each of these sit es a rc c:o ncelllnlling o n the improvc m ent of ma ize gl' rmpl asm fo r th e na tion a l progra ms in A fi•ica. :-\\no ther nt'w d imellsio n in I ITA 's l'vl a ize Rc'searc h Progra m ,vas the posting o f a breeder ,,,ilh Ihe na ti o nal progra m in Za ire. Ten years of resea' rch and breedingfor resistance to 1naize streak-virus (MSV) -a n A Ii-ica n l'lldl'mi c disL'ase was co mpll'tl'd in 1985. It is UIll' o r lhl' IllOS t l'conom ica ll y i 111 po rta n L d ise<lsl's in Sll b-Sa ha ra n i\\ fr ica a nel widd y d istri bu IIx l ac ross LilC' CO il li !l en l. I t ca n be insig nifica nt in so m e yea rs o r a rf'as bu t then strikes with d evasta ting c ro p losses ill o ther yea rs o r placl's. Fo r exam p le, a Sf'\\'t' IT \\ IS\\I epid c mic occurred in 1983 a nd 1984 in a ll th e savan na ZQ ll l'S of \\V est Afi-icCl: .md a scverl' o Ulbrea k was re po n ed recentl y fro m Zamb ia_ Ango la , 1\\ lozam biqu C\", a nd so m~' O t her SO lIt Iwrll Ali'iean Co ulll ri es. T'he Inslitull\"S wo rk o n streak r{'s i s t anc~' is a classica l (, xampl e of a wdl iocusscd and targe ted bn'l'Cling program a il11 l'd at so lving a serio us cOllstraint to produ cti o n o rmai z(' in Africa. In \\'o lved in this ITsca rc h were II TA brecd ers. en tO mo logis ts, viro logists. and pathologists , o ne o r IWO C I \\ I\\ IYT maiz(, breeders beginn ing in 1980, and scielllisls [i'om m any Afri ca n na ti o na l programs. Th e la u er ;:lIso pa ni cipated in the internatio na l progen y I ('SI i ng a nd th e sl'lec l io n of I hl ' i;l mi li es tha t la l lT canst i t u t cd th e ex pl'ri m en l<t I va ri c li cs. As a resu h of t hcsl' CnOrIS, there a I'e now strea k resista n I va ri C-lies a nd hybrids ava i Ia bh: to cover a I t hl' IT leva nL eco logil,g in A li-ica and \\vith difl(' rl'l1lm£l tliril y ranges) g ra in co lo r , and tex ture to III l '(' I thl' prl'i(Tl' nCeS o f Africa n I;trnw rs ill va ri o us countri l's. St rea k resistant \\'aricty tria ls Wl' rr sent upo n requ C'st 10 mos t or the Arrican counlries. a nd the t'fl'Cdback\" indicates tha I the resista nce is siabh: ac ross th l' co ntin ent. X/Ian )' req ucsts fo r a dditio na l secd s o f selecled variet ies have becn receivcd a nd di spatched. S tJ'eak resista nt v; lri C' li es ::IIT a lr(,ady comn1t'rc iall y g rown in a t lea st six coulltri es ~ N igeria , G ha na , Bl'nin Republic, T ogo. Sa o-I'o lll t\" a nd Zambia -and probably 0 1 hers. If ava ilab k va ri eti es wer l' to be adequate ly lI sl•d by a ll natio nal programs, th l' pro blem Orstn'a k in Africa wo uld be so lved. Part of the work in the streak resistance breeding program was devoted to conversion of selected non-streak resistant varieties LO resistan t varieties by backcrossing. The vari eties were selected based on their performance in severa l African countries. Converted varieties \", .. ere included in the streak resistance variety trials in the last few years with encouraging results. While emphasizing streak resistance work, scientists were not negl~cting other constraints to maize production in Africa. Drought was particularly serious during 1983 and 1984. The I ITA/SAFGRAD team based in Ouagadougou, Burkina Faso concentrates its research work on the d cvdopment of techno logy to minimize the effect of drought stress. Ti ed-ridges, introduced in Burkina Faso by the I1TA /SAFGRAD Agronom y Progra m , have helped to reduce runoff, increase soil water reserves, and markedly increase g rai n yields of maize and other crops in the predominate soils of lha l counlry. An implement adapted to animal traction and d esigned for tie-ridging was farm tested o n a la rge scale during 1985. Preliminary reports indicate tha t it has possibi lities to make ridging less laborious and more attractive 10 farmers. Early ma turing varic ties, even though potentiall y lower yielding, have an o bvious ad van tage in short ra iny seasons. Breeding earl y varieties with 90-95 d ays to ma turity was emphas ized in the past in the Maize Research Program. However, experience in the pas t few years has shown tha t in drought years a closer fit between the effective leng th of the growing season and the varietal time of ma turity is required . Farmers in the Sudan Savanna may be better off planting evell earli er maturing varieties a t least in part of their fi elds. Two ve ry earl y-maturing local va rieties with acceptab le yield po tential were identified by the tea m ill Burkina Faso. Efforts continue to further improve yield potential, agronomic characteristics, a nd adaptabi lity of these varieties . "},{"text":" maize project, supported largely by the Government o Nigeria, was intensified in 1985 wit h emphas is on deve lo pment o fthree-\\va y cross hybrid [Q cnab le production of c hca per seeds and obta in more sta ble sced produc ti on. On-farm dcmonstrat ion tria ls were condu cted in a lm ost a ll the sta tes in Nigeri a. Ag ronomi c tria l were a lso carri ed out in thc different agro-eco logica l zones of the coulltry. Two prival seed companies (one formed in earl y 1985) produced enough hybrid seeds to plant abou 40,000 ha in 1986 compared with onl y 6,000 ha in 1985 . "},{"text":"Figure 12 . Figure12. Rainfall and potential evapotranspiration in 10~day periods at Kamboinse J Burkina Fa so in 1982 (a \"goodJJyear) and 1984 (a Hbad JJyear). "},{"text":"~ __ ~~~~~~_~~t~ r-May ~Jun~ Jul-+-Aug-t-Sep -t-Oct -l va rielies lha l norm all y flow(' r ancr 50 d ays llC'vc'!\" reach('d 50 0 0 silking. <,V(' 11 ill hydromorphic soil. "},{"text":" by lIT A ha v e s h own y .:eld s uperioritJl ltllder differe11l mauage1ne Jl t and s tress conditions. Hybrid Maize: Stable across Environments and Different Management and Stress Conditions? I s hybrid maize in the tropics less stable than open-pollinated varieties as commonly believed? Based on UTA scientists' experi e n ce in West Africa, the answer i \" somet imes\" but not \"alwa ys.\" T h ey have observed the performance of hybrid maiz across diffe r e nt en vi ronm e nts (forest vs s avanna ), management (good vs poor) and stres (drou ght, streak virus, and Striga ) conditions in Niger ia and a few neig hboring countries T Il(' hybrid varict), 8322-1 3 dcvdopl.•d by 1 IT A has shown wide . .' ada pta tj on a nd s lI'('SS tolerance. "},{"text":"vi l ' Us a nd Striga hermonthica. U nd er a rtjfi cia streak pressu re, it produced 45°0 more gra i th an th e slI'l'ak resista nt POZ;:l Ri ca 7843-S R llsed as a COlllro l. The yield in c rease or thi hybrid und er na tu ra l Striga in fcs ta Li on a 1\\ lokwa. Nigeria was 270,0 ,0 1110 1'(' tha n the to yie ld ing op(,l1 • poll inaled va ri ety. This show so me ach-a nt age of lin e development resista llt bn.'(•ding in maize in th e tropics where various stresses han' afli:c tccl yields. Results of 1985 h ybrid maiz(, Oil-fa rm dc mo nstnllion tri a ls co nd uc ted b y farm crs in IWO ecologica l zo nes o r:,\\,igcria forest a nd sa\\'a nn a show the yil'id suplTio ril Y of s(, lected hybrids sti ch as 8322-1 3 a nd 8~~28-1 9 un dt ... dim ... t11l managemcll t co nditi o ns. \\\\' ith l'('co ml11 e nd ecl good l11a nagt.' m e rlt. th e two h yb rid s yielded 32°,, 1110I'e in bOlh Ih e forest a nd sava nn <l zoncs than t1wOptll-pollinaltd TZSR-\\\\'-I or 6.5 1/h 3 "},{"text":" and 7.+ L/ ha ITspcctivcly {Tabl(' 2<1 . t\\\\•trag(• yidds of lhe-IwO h ybrids u nde r poo r mana gl'-l11l'nt were 3.7 t/ ha ( 37 n o h ig htJ') in th(' fon'sl zone a nd 3.0 t/ ha (54°0 hig l1l'rl in the savanna zone..\\pproxim:ltC'l y 6,000 heelan.'s of hybrid maize \\\\'(.' IT grown coml11('J'c ia ll y in :\"J iger ia in 1985, but it is ('s tim alcd Lh al -1 .0 ,000 hcc1<lI,(,s will be pla nl('d in 1986. Th t, Success sLOr y o f h yb rid ma ize in pans or East Africa. No nh Amnica. a nd Europe co uld bt, n 'p<'all'd in ' Vest Afi'ica in Ill{' fUIUIT. "},{"text":"•• L~ss 111fI1l 5(JO 0 o!ruommtlldt dftrfifi-ttr'lfJplied.poor wud (0 1111\"01. or/l/ai-tt growlI IIIIIfn-fJlJor suif {O//{lirilJllJ. Western Left J an enlarged close-up o/weevil attac king m.aize ears iu s torage; a weevil-s u sceptible varietY J West ern Yellow (a bo ve), suffer ed 70 (lo kernel damage cOlnpared w ith Jess than 10 00 Jar the resisl,ant ye llow flint -d ell l hybrid 8329-15. Weevil Damage: a Comparison of Different Maize Varieties A fri can m , aize farme rs suffer heavy 'losses bec ause o f grain deterio ration durin g storage, and Sitophil1l,s weevils are among the worst pests that r edu ce eating quality and seed viabi li ty. To dete rrnin e the s u sceptibility of22 maize h ybrids and open-pollinated varieties to weevil attack under long-term s t o rage at room te mperature co nditions, scientists co nducted preliminary t ests during 1985. Also, they e xamined seed viability every month through germ.ination tests. "},{"text":"90 0 0 ) fo r 8329-1 5, 8425-10, and SCkOlI 8 1 TZSR-\\, V-J blll was redu ccd lO vny low levels ( < 40 0 0 ) for SO I11(\" Olhers (T ab le 25). Two orthe widely grown o p(' n-polli nalcd \\'a ri elies in \\Vest Afri ca -EV 8443-SR a nd \\\\Ies tn n ' Vcllow -ar(' hi ghl y susce ptible to weevil a u ac k. The former, [I strea k resisla m va ri el), deve loped fro m C I i\\H\"IYT's tropical popultnion La PoSta , is prt'se ntl y grown in Ghana a nd R epub li c of Benin. \\\"'estern Yell ow was d cn:loped by the Nigeri a n I nstillilcof Agri cultura l Research a nd Tra ining. Also, sLudies show th a t th ere is wid e ge neti c di vcrsit y in ll TA 's ma ize ge rm plas m in rela tion to suscep tibil it y to wCl.: vil a ltack. Severa l fa cLOrs 3 1T known LO innu encesuscc plibi lit y of ma ize to weevil attack: a light husk COVlT he lps ITdu ce infes tation in tht, fidd , a nd kernel ha rdn ess may illlcrferc wit h o\\'ipos ition a nd fceding. i\\ lo rc detailed gcncti c and Cl1tomo logica l studi es a r(' und erway 10 con firm t hest findin gs a nd d ctcrmin e more precisely the mec ha nis m of res ista ncc. "},{"text":" = IIIhil,. r = r ,lIollJ. D = Dmf. F = F1i,.t . \\{((III oJlltt\" slIIl1plts ta~1'II aflrr jil\" 1II0001Its;\" s/omgf .-/ = / -/0'-' o . /0=9/ -l()()O 0 ~trllrl dUlllagr . ••• . l/tml fijll1\"t sall1plts lakt l1 (ljIu jOllt 1II01111.s ill slomgt .•• •• / = tigl1l , 5=1005t. of maize varieties developed in the past by CIMMYT and lIT A "},{"text":" Po p 66-S R T ZB Gusau-S R • Shorl/J!rml 1)'/)1. uQfM = qUI/fir)' I) m/l.in //Ia izl'. "},{"text":" '1II1 rifl/lfa Nigt'rirw/omlio lls:Ikfllllr. 1I0rill . and Samam .  •• Under arlijirial illJeslatioll oJ lenjlwpperJ mr')'illg IIIllizr slrrnk virus( . .  \\IS I•) . ••• / = excel/wi. 5= vr')' pOllr. is cultivated stalk rots are common diseases, and in the tropics fields are infested at a range of 5 to 400/0. They usually d e velop during the grain-filling period, cau se premature d eath, and, as a result, lig ht and undersized cobs. Affected plants also lodge and t h e ears become prone to rot dalTlage . Major causal agents in the lowlands of Africa are Fusarium monilifoyme, Botryodiplodia theobromae, and Macropho1nina phaseoli. Other species a r e prevalent in the cooler environment that c haracte rizes th e mid-altitude and highland ecologies. I n th eir l' nons 10 cit-vciop sta ble hig h-yid d ing ma ize gc rmpiasm, I ITA scic. :ntisls ha ve clL'vt:lo ped £l modifi ed effi cient a nifi cial inocu lalion tcc hnique. Th is ena bles th l' pla nt breed ers to id e ntiry a nd s<:i ec t sta lk rOl•rcs ista nt ma ize genol ypc-s. The pa [hogcns a rc isola tcd fr o m inr('c ted mai ze stalks ~lIld /o r seeds using POl a to Dex tros(' Aga r ( PD A) as a culture m('dium . La ter th e rungi arc cultured on white ma ize g ra ins u ndtr oplima l co nditions ro r Liucc wee ks. Fo r in oc u la tion. spo re susp4. :nsio n is prepa rcd w ith a pproxima tcly 2.5 x 1()6 sporcs/ml. Thc fi rs l elo nga tcd il1lcrn od c rrom thc soil le\\'('1 is inocula ted one wce k a n er mid-silk . The modifi ed inoc ulat io n method co mbines drilling a nd inoc ula tio n simulta neo usly by lI'lili z in g a I c m' 2 spo nge a tt ac hed to th e needle ora syringe. The need le with th e sma ll spo nge is dipped into the in oc ul a ti o n. As thl' pla nt is drilled ) in oc ula ti o n is sq uCL 'zfd in [ 0 lhe pla n IS. This mcthod red uces t he la bo r in vo lved by ha ir co mpared w ith sepa ra te drilli ng and inocul at ion. 82 Top photo : A Hew imloc-ulation procedure using tlu'ee pathoge ns to dete nnine slu'ceptibility 0,. resistance to s ta lk \"ots ill maize. L ower photo: T wo maize stalks split. to s how a res ista nt v arie ty (left) and a s'flsceptible o ne (rig ht). "},{"text":" FusariulIl was consistentl y th e mos t virulent. Inbred s 1368, 2096, and 9091 were rcsist<llll ac ross a ll the p a thogens while inbred 9490 \\vas susce ptible to Maize Pa thogens a ll. On th e o th er ha nd , so me inbrcd s showed diffe r e nti a l reac tion to th e pathoge ns. Fo in stan ce, 9450 is susceptible to I'ilsarilllll bu res ist<tlll to BOllJo diplodia and t\\/farro/J/wl1/illa Th erefore, CH•n though it wo uld a ppea r th a tlh pathogen mixtuIT d oes not g ive hig hcrrot sco re th an in oculatin g o nl y with Fusarium , the scien tists use th e pathoge n mi xture lo r their routin gt'rll1plasll1 l•val uati o n. This tec hn iquc o f stalk rot resistan ce screen in g is bein g used in tht: lITA hybrid mai z program. Si milarl y, the foll owin g maIz popula li ons/p ools a re current Iy being s ul.~j ect ed to improve m ent for sta lk rol resista nce T ZESR-W , Pool 16, TZPB-SR , a nd Back-up LSR-W. "},{"text":"C rop infestation by the parasitic weed Striga continues to pose a serious thre at to maize produc tio n in Africa. The solu t ion to the problem. of damage cau sed by pests and pathogen s in maize adopted at lIT A is to identify and develop varie ties with broad spectrum sta ble r esistance. The backbone of an effective breeding program for r esistance to a pathogen is effici e nt and r e lia ble scr eening technique s.Screening rorSlriga rcsisulI1 c(' is co ndu c tcd in three stages w ith til(' o bjec ti ve or id entifying gc rmpl as lll res istan ce emb ra c ing th e mec ha nis ms in vo lved in lhe host/pa ras it c intcraclio n. SJriga seeds w ill gcrmi mtt(' on ly in res po nse 10 c hcmi cal sLimulants pn.:senl in rOOl l'x ud al(' fro m a SlIsCt'p lib le host. T o id enti ry no n-o r low-stimul a nt ma ize ge no typ es, Siriga seeds a rc sterilized and p reco nclili o ncd for seve n d ays o n mo ist fibre g lass filter paper in Pctr i d ishcs o r p iasl ic g row th bags befo re pre-germin a ted l11 <1 izc seed s a rc introdu ced . Ge rmin a ted Slr(ga seeds co u ld be o bs(Tved within thrce da ys. TIll' g rowth bag tec hniqu c is ma rc effic iellt because it is easier to ha ndle . ~lI1d ge rmi natio n can be exa min ed using a ha nd lens as o pposed to loo kin g in th e Pc tri dishcs und er the stereosco pi c mi crosco pe. This ma kes it poss ible to exa mine mo re materia ls in a rela ti vel y s ho rln limC' . Screenin g in th e g reen ho usc is co mpiL\"m cl1I a ry 1O O b SlTva Li o ns mad e in th e la bo ra to r y_ f\\ laize genotypes a rc o bser ved ro r nOIl -o r low-sti mulant prod uce rs over a longer pe riod o r cro p g row th in vc: rmi culile. Seeds o rthe parasite o n filte r pa per a t t he bOllo m of th e po t a re exam ined ro r gtTll1in a ti on. In additio n, li nes w hi ch support Siriga a ttachment a nd c mergence nu\\ ~' 1 )(' iclt:nlificci . Th t., screen house rn ethod has bee n mod ifi ed to In a ke it ma rc eITi cicIll and ras ter to evalu a te a la rge number of m ~li ze ge rmp las m. The method in vo lves th e use o r ji fly POts (6 cm card board pots) wit h vermiculi te rep lacing soil. Thf' looscness of th e ve rmi cu li te pelle L s ma kes it e~\\s i l' r L a 84 Left , germ .illlllioll of Strigfl seeds ill \"esp o m,'e to maize root eX1td ate ; \"ight, reac timl of Inaize leaves to .~trig(/ toxic extrac t : one o n left s usceptible, ce\"te r res.:stant. (Co nh-o l on the \";g ht inject ed with briffe ,'') R edflowered Slr(If(l ( S. (lfilllira ) has k i lle d t hese maize plants in the fie ld. "},{"text":" rn;sllml. 5 = liiglt(l' slIJ'rr/lliMr.     "},{"text":" o r ri ce lines a nd d cvising app ro pria te managc1l1cJ1( practices fo r the m aj or ri ce-g rowing ecologies of Afri ca cOillinlic w be thl' ma in thrust Oflhis resea rch progra m . Rice is m a inl y g rown in r:1 in fcd upla nd , r<1 in ftcl low la nd (h yd ro 111o rphi c ) a nd lowla nd /swa mp eco logies in 3 1 ri ce g rowing countries in su b-Sa hara n Afri ca. In som e coun tries the per capi l::t consump tio n is eSI il11cllCci a t mo re than 100 kg /yea r. De mand (' O r r ice is i nc rcasi ng a nd g rl' C:l l e I' prod u c ti o ll is need l'd to fecel mo rc peop le a !lel reel uce costl y i 111 ports A few countri es (N igeri a , fo r exa m pit) ha ve ba nn ed ri ce impo rt s as ,I m ea ns of encou raging loca l produc ti o n. "},{"text":" Requests for seeds of elite 'r£ce varieties f1•0111 [ITA continue to inc1\"ease. In 1983 n ea rl y 860 kg of seeds w e re sen t to sevcra l na ti o na l p rogra ms (o r ex pe rime nt a l p u rposes a n as initia l seed stoc k for fu rth er multipli catio n. In 1984 and 1985, the su p pl y was 1183 a n I ~l->-1•2 kg. respl\"Cl ivci y. Bt'caw;c o f t he in c reasing d ema nd. liT. \\ 's ca pa b ilit y to prod uce goo qu a li ty seed for na l io n a l p rogra ms is b eing s tcp ped u p. To i111prov e the efficiency of rice technology transfe1' in Africa, an internationa testing netw ork began to function in 1985. Ca ll ed t h t' Intc rn a ti o na l Ri ce T esti n Program fo r Africa ( IRTP-A fri ca l. it is ,. coope ra ti ve progra m in\\'oh-i ng IRRI , W A RDA a nd liT A. T his ne two r k dis! ribu tl'S spec ific ricl\" nu rse ri es fo r ta rge t ecologies a nd b ri ngs ric sc ie n tis ts toge th e r fro m seve ra l Il at io n a l p rogra ms 10 int e ra c t a nd p arti c ip at e in th a ssess m e nt o f les t lines . "},{"text":"20° 0 T in trials by resea l'c hers in th e-Na tio na l C('fca is R esca rch a nd Ex tensio n P roj ec t (Ta ble 32). \\ Iult ilocati o ll tria ls ill Eunwrs' fidds in th e COllntry co nfin l1 (:ci this resu lt. Rig ht, r£ce v a ,.,:e ty I T A 306 pe ,/o rms w e ll unde r hy dro m o rp hic a nd \" \"'lgated soil c ondit io ns ; n ow un derg oing Im'ge -scale testing in Ca ,ne r oo n . ab le 30. A v e rag e y ie ld, days t o m at u r ity , an d plaut height o/t wo IITA rice v a rie ties I T A 222 and I TA 306 a t  "},{"text":"~ yield ed 7.8 t/ha. a nd is being in creasin g ly grown o n r. : \" l.rms in va rio LI S pa rtS o f' th e co un try. ITA 222 is a scl('cl io n from the progcnyof lhe cross i\\ lahsuri /TET 1444 a nd IT !\\ 306 from TO, 49+ Sci /TO, 711 /BG 6832. The parrnt varic ti es in thl'sc crosses, na mel y i\\ la hsuri , l ET 1444. and BG 6832 show di rIcl\"cTll favo rable traits. the co mbi na ti o ns of w hi ch h,ln' res ult ed in th c su perio r perfo rm a nce of ITA 222 a nd ITA 306 un der African lowla nd co nditi o ns. TO, 494 Sci and TO, 711 arc I ITA lincs. . ... -::\"\"'\"-........ -:-,.. .-.-Lo ng slendeJ' gnlins of the high-yielding rice v ariety ITA 306. "},{"text":"• SOl/rrr: . \\ •a/ jollfl/ Cereals RI!Sf'llrrllIllstitlllr. 1985.    Tab le 31. EntJ-ies with the highest. y ields in the Coo' rdinated Rice Evaluation Trial conduc te d at eight locations in Nige1•ia.* "},{"text":" Figure 13. Mean rr:ceyield at different s ites in a hyd,•o111.0rph,:c v alley at UTA iu }905. (Tlte v alue is the m.ean oj e ight rice lines ; experinle nt co\"dllc t ed w ithout ferti lize1',) "},{"text":". • :~t~f•~;•!:~~.:5',~t~:~~;.:~r~~\":'6•.~:;•~;5;\"~ * Upper Hydromorphic * Lower Hydromorphic One of t he bas£c p ,-ob le m s affec t£ng rice p rodu c t ion in lowe,. hy d r o m o ,.ph ic lands: ox£dize d iron (,-ed c olOJ-) in s eepage w at e'-. "},{"text":" Severa l fun gi arc in cr imin a lcd in lhissy nclro m c, lhe IllOS l common o nes being species of Sllroc/adium, ClmJUlflr;(l, a nd Fusarium. Gra in-Sli cking insects a re a lso know n LO pred ispose lh e g rai ns fo r infection by th cse o rga nisms.T o idenlifyso urccs of res ista nce to this disease problem. IITA scie nti sts tested several tho usand exotic a nd m a n y loca l rice v(lri cti cs from Africa in th e Institute's hig h rai nfa ll statio n a t O nn e. : in Ri vers Sta te, Nige ria. Sc reening of progeny of crosses of breed ing ma te rials und er severe disease press ure there showed th a t ma ny proge ni es fo und res ista nt ca me fro m l ll rrsisl{l1I110 gmill discQlomliol/ ul/d blusl. "},{"text":" Thl' \\'irus ca uses yellowing a lld stunting orrin ' piallls lead in g In in co mp le te l'T1lCTgc nc(' o f panicles wi th sttTile g ra ins. '\\'rllow mo tlie ca n be transmiu cd to hrailh y plali Lli b~ sa p in• oc ulali o n and by insec ts. bUI no seed tra ns-milSs ion has bccn obscrn'cI in l 'x lJt'ril1lf'11ls with m ' lT 5.000 stxd s liTJI11 infec ted piants. Also, th t' \\' irll ~ has bec n puriri t'd at (I TA :lnd a h ig h titre <llll is(TUIll prepared . Va ri o lls slTol ogica l tec hniques. illt: lud illg till' ~e ll ~i l i\\'l ' E II 7.Y II H•-linked Immullosorl )(' llt , \\ SStl~• EL ISA ). ha ve b ('(' n sLi ccessfully applied with this anli ~erum . . \\ co mbin;1tion o f it \\' i s u ~d a s~(' ~s rn e n t of\" s~ mplollls ::Ind rd.ll i\\'l' virus a ntigen co nCentration in tiss llt's as d l' tnminl'd h y E LI SA havl' proven useful to diffl'r<. 'llt ia le resis ta nt / tol e rant lilli'S. \\,\"i lh Ih.: fonnn mtlhod. sc ien tists ha \\'{' l' liminatcd hi g-hl y s uscept ible lin t'S su c h as IJC 90-2, I R 5, I R 8, and I R 20. LAC 23. ~I o robc rckall, a nd OS 6 \\\\'I'n ' hi g hl y LOi eram but cO llla illl'd the \\'irus as dt'termined by EL IS,\\ . , \\mong Lil l'S{, rice \\'aril,ti es. LA C 23 had th e leas t am o ullt of \"irlls a ntige n . I'\\ o ne of th e O. sfllil'alincs ll's ltd W{TC imlllune. I n th e dev('lopml'11l o f virus-fh,t lin es) th l' sc ie lltists havc found it difficult to obtain desirabk geno typ es from cross('s invol ving O. glllberrima and O. satir'a, A lso. 0, glaberrilllll and 0, bar'hii hav(' man y und cs irabk' characHTs th a l r('s ul! in low yields, Recog niz in g ilw ('a.sr or tra nsfe rrin g tht , gcn e(s ) lo r resistan ce [i'om O. salim as an im111 l'd ia tc goal. th ey int ensified 96 RYM V-t olercw .t donor Mm'obe rkall and t he se mi-dwa ,j I TA 230 w hic h is s usceptible to th e v ints but. h igh y ie lding 'l\"o t. infected ; th e middle plant. -(I (.\"'OS8 betwee\" lhe tw o -ha .... tole rall ce plus v igo r , A ll three we l'e artific ially iuu()c lliate d w it h th e v irus at lhe seedling stage, th eir c[fons LO inco rpora te tolerance to th e virus rrom O. saliva into bn'eding lines intcnded for irriga ted, hydromo rph ic, and sha llow swa mp ecologies. Va ri c li ('s id entified in earlier sc ree ning tria ls as to lera nt we re used as donors. "},{"text":" Th l. ~Y have icicll lifj(,ci an ,\\ rr ic<l n-o ri g in all'd shru b Sesb(luia mstrata a S H POll' llli a l nitroge n suppli e r 10 rice crops grow il o n hydromorphi c la nd. ,\\ Iso l fidd tests ha \\' ~' shown Iha t it ca n thrivl' \\wll undt'r flooded co nditio ns. \\ Vhell pla il lcd with rice in a spac ingor200crn x 40 el11, S. I'Ollmlfl r idded 2,465 kg/ha o rfi'('sh matte r o r +31 kg/ ha or dry malter wit h :I nilrog('n co ncnllration or2.6°o. The 1985 field expe rim cnts showed a sub-Sl<Illlial ~ il'ld inCrl'::l Sl' in low la nd ri n' w h l'n S. /'O.lIralo cutti ngs (bu t Il l) nit rogl'J1 f(; rti lizer) \\\\'C IT add l'd LO lhl' soil as rn u<. :h as 42. 1 a nd Sl'sb(/l/ifl rIIJlmln -afast growing Africanoriginate d leguminous s lu'ub -is a poten tial nitrogen s upplier fo'r lowla 'td rice. (Show n he n at an early g row th stage in aflooded rice c rop') 60.3(1 0 with th e a pplicat ion o f\"t wo and ro ul\" tons or S. ros/rata c lillings, res p l'c ti vl'! y, a 1 rOllr wee ks a rt cr tra nspl a nting (T ah le 34) . This co ntri-bUli on or S. rostra/a L O lh l' ri c(, yield ) however)was nOt sig n ifi c<J n t wh l' n so il fe rti lit y was hig h with lh{' add it'iOIl arGO kg N/ha. "},{"text":" ya illS , S\\v cc t pota toes, a nd aroids ~ m ajo r so urces offoeel energy {or millio ns o f people in the humid and sublllllnid tropics -received priorit y a llcntion in that o rd er during 1985. Scientists concentra ted their c(fo n s in fo ur direc tio ns : (1 ) im proving lin es and populations Oflh csc root a nd tuber cro ps to ob ta in hig h sta ble yields, resistance to majo r diseases a nd pes ts, and prod uc t qua lit y acceptable to prin cipa ll y Africa n consum ers;(2) con trolling cassava mca ly bu g (CM) and g recn spid cr mitc (CGM ) thro ug h bio logical contro l ; (3) coopennjn g close ly w ith na ti ona l programs and tran sferring impro ved techno logies to the m ; and (4) tra ining naLi o na l scientists. "},{"text":" ntist.s int erac t w ith sta ff members of o th er progra ms (suc h as the Farming S ys tC' ms Program) in th e im p rove menl of c ullUral p ra c ti ces a nd in co ndu ct.in g on -fa rm tri a ls and the Vi ro logy U nit in slUci ics o n viruses a nd virus indexing. Also, II TA coopera tes wi th th e l nter naLi o nal Cent er fo r Tro pica l Agric ulture (C I AT) in Co lo m bia , Sout h A m eri ca in cassava im p rove m ent a nd bio logica l contro l, a nd the Asia n V cgc la b le R esea rc h a nd Development Ccnter (A V RDC) in Tai wa n in swce t pota to im provem cnt th roug h exchange ofma tcria l, tec hn ica l info rma ti o n , and inter acti o n of sla n' m em bers. During the year, scien tist.s tes ted their selec ted and improved materia ls under specific enviro n m ental conditio ns in cooperatio n with na ti onal programs, including Prog ra m Natio na l i Vra nioc (PRONAM) in Za ire, Ca m eroon Na tio na l R oot C ro p Improvc m ent Progra m (CNR C IP), R wandan N a tio na l R oot C rop Improve mclll Prog ra m (R N R C TP) , a nd J a maica Nati o na l Roo t C rop I mprovem ent Program (JN R C IP) . Th e P rog ra m Na Li o na l Nl anioc m a rk ed its tellth ann ive rsar y a nd 10 years o f TI TA 's in vo lvc m cnt in cassava improve m ent in Za ire. Nlajo r improvem ents made in 1985 include elecu•iflcat io n , insta lla ti o n of a waler system , a nd co nstruc tio n of a tra ining ccnter at PRO NA ~/r's headquarte rs in~/I ' Vll az i . PRONAM has becom e a il e o f th e bes t natio na l prog rams wo r kin g solel y on cassa va wi th morc than 10 natio na l sci entifi c sta frh o lding M .Sc. degr ees <: l ndlh rec ho lding Ph.D. d egrces. Severa I ma rc staffare und ergoi ng lVr .Sc. a nd Ph .D . courses. "},{"text":" SW('C't pOtalO weL'v ils are vcry destructive pes ts ofs\\Vc('t potatoes in the tropics. Indi vidual con tro llt'chn iq ues . such as modera tel ), \"\"e('v i I rcsista n t varieti es a nd so me cui tu ra I practices, ha \\\"C' shown sO l11 e pro mise bu t to a Ii Jl1 i tcd degree. 1 n tegra lion of I hesc con tro l Ill t'asu res ga vt' the best ovcra ll results.In the following pages, notable ,-esearch highlights during the year are briefly described. More complete information on these topics and those mentioned in this Executive Summary can be obtained by ,-equesting the Annual Report of the Root and Tuber Improvement Program _ Distribution o/imp1'oved CaSS(lVll planting materia l is in c J-easitlg but the de m ,alul/oJ' plantable sl,em c u ttings/al' exceeds the supp ly.Impact of IITA Cassava Varieties F armers in Oyo State -one of 19 states in Nigeria -grow cassava on s hghtly more tha half of their cultivated land and IITA cassava varieties now cover from 30,000 t 40,000 hectares or about onewfifth of the land planted to this crop. These figures ar based on a 1985 survey of farme r acceptance of IITA varieties in the state over the pas decade (Figure15).Tre nds in th e ado pti on of thesl' improvt'd varic:ties l-c fi ec t a n inc reasing suppl y of pla ntable ste m C llt Lings a nd th e grad ua I rcplacc ll1 enl ofalcasl 40 traditional va ri eties. The National Seed Service afN igeria. O yo S tate 1 \\l in islry of Agricll lill re~ and TEXAGR I fa rms £II Opcj i a rc lhe main saurces afplantabk ste ms fa r farmlTs. "},{"text":" Figure 15. Local governme nt areas in Oyo State, Nigeria s how ing cu lt ivation inte n.s ity of IlTA cassav a v arie ties in / 985. "},{"text":" palmkern el slulrt. .. m d SLyrofoam ) held by LIl(' Adv anced teclwologyfo r (l hig h a\"d stable produc tion of IllItural e nenlies aftlte c assa va m e alybug . "},{"text":" Fig ure 16. A low-cos t unit /0\" 'ma ss rearing 0/ natural e ne u'1ie s a/the cassav a 111ea ly bug. (Designe d/a )' u se by national biolog ical co n h -ol proj e c ts w he r e e lec t\"ic al po w e ,' may be irregulat-01' unav ailable.) "},{"text":" E. /ojJu.i  as a new hosl. "},{"text":" This ad a ptation to t he newly imrodu ced parasilOid pron'd 10 be vn y bst. On n umero us occasions hYP('rparasitoids 'vcn' already pres-(' III in th e firs t sa mple taken Qllt'to a ft'w mOlll.hs a f'lCT thl' rt'l casl' or E. lujJe?,;, At TEXAGR I ra I'm Il ca r Abl'ok uta, Nigeria, h ypel'parasiLOicis reached 52. 1 0 0 four mOlllhs a fte r the re lease (Figure (7 ) . f arther away li'om tlw rel ease Si lC, E. IOjJeei arrived la lc r an d by M a rc h 1983 h ypnparasiLOid s had 1l0l Y(, I built up Ih eir popuhllions to thl' same: hig h levd as o n 'rE XAG RI f~lrm. H ype rparasitism did not prevc nl rapid di spe rsa l or E. /ojJui and f' ITiciellt biological control o r th l' cassanl mea lyb ug in the area. "},{"text":" Thesc figures werc used to ca lculall' the number or insec ts per 100 random l y collected cassa va (ips. T a b le 35 shows lhe reciuClion in bunch tOP d ensity an d lhe accompany ing c hange in l ht' abund a nce or E. topczi.Bt:cause or lhe diminishing pa rasiwici dl' nsiti rs, th e h yperpa rasito icl s were unabk to mainlain their perccl1 lagl' hyperpa ras ilism be twl't' ll l \\l arch 1983 and Dl'cl'lllber 1984.The res ult d e monstrates a positive d ensit ydependent rela ti ons hip in lime between hyperparasitoid and E.lopezi popula ti ons.The sa me result \\vas obta ined when rhe pcrcenragc hyp erparasitism of one sa mpling period (March 1983) was registe red se pa rately for diffe ren t E. loped d e nsiti es in d ifferent loca liti es (Figu re 19). The higher th e !lumber or E. lopez; emerging from a given sa mple of 10 bunch LOpS r\"om on e fi eld , t he hi g her the percentage hyperpa ras itism. Only a t the hi ghes t hos t densities wcrc th e hyper paras ilO ids unable LO calch up with th eir host. The co n-c1usion? I n a give n pe ri od, th e hyperparasi toids reac t in a positive d ensity-depend ent \\vay to host popu la ti on in differen t loca liti es.\\'Vh ere E. lopezi sll cceeds in kee ping cassava mea lybug popU lations low, its ow n popula ti ons do not reach th e same high iL-ve ls th ey often had shortl y after esta blishment. In view or th eir density-dependenl. behav ior, hyperparasitoids are expected to p laya less important role 110\\V tha n during the establishment phase of E.lopezi.Based on fi eld obsC ITations so ra r, HTA scientists d o 110l ex pec t the m to pose a da nge r to th e future progress orthe Afri can biologica l control program .T a ble 35 a lso shows the vcry marked collapse of the indigenous predalOn; a nd es peciall y the coccin cl lid popu lations. Like coccinellids on man y Ol her c rop pests, th ese beetles a rc ma in ly active on hi gh host de nsit ies. Beca use E. /ojJu.i redu ced their food supp ly, th eir me mbers beca me reduced. All oth er predatOrs a re Illllch less CO llllll o n a nd ha ve a li mited impac t. "},{"text":"Figure 17 (Figure 19 . Figure 17 (Left): Mean nu mber of Epidillowrsis loped (w hite colw'nll) and its hyperparasitoids (g rey) ( + ~ SE) rearedfrom /0 bunch tops and p e r centage hyperpa rasitism at different distallcesfrom the \"elease site. (Sa mples take n in March 1983.) Figure 18 (Right) : Mean percentage hy p e rparasitism. in south w es tern Nigeria during four s u rvey periods. N per 10 tips Hyperparasitism (%) 60 "},{"text":" , screening crop germplasm for tolerance to environmental stress makes special demands on land or glasshouse space, labor, expensive equipment, and the time of scientists and technicians. However, experiments indicate that the tissue culture method can be used for the first step in screening of cassava germplasm for tolerance to acid soil. This could assist plant breeders by eliminating a large portion of susceptible germplasm before field or glasshouse screening takes place. "},{"text":"Figure 20 . Figure 20. Number of cassava clones among 10 varieties that had more than a 40 °6 survival rate at different pH leve ls in the culture medium (five weeks after inoculation). "},{"text":"Figure 21 . Figure 21 . Cassava mosaic virus (CMV) score of three cassava varieties two to 12 months after planting. "},{"text":" Figure 22. Relatio'lship between number of 7-gram white yam microsetts per hectare~ tuber weight, and tuber yield (' Iha). "},{"text":" g work began at lIT A a d ecad e ago, sele c t ion of new promi~in g water yam cultivars from seedlings oflill1ited amounts aftrue seeds have not b een s u cessful in produc ing genotypes with acceptable tuber s hapes. But sustained efforts at sexual s eed produ c ti on and itn.proved nursery evaluation are beg inning to p a y off. ' Va ter yam D iosrorf'fl a/ala ) co mes a ft er whitt' and ye llow yams in lCl'ms o f spatia l spread. in tcnsit y o f c uhi v~tli o n l a nd prcrcrl'll c('s in consumptio n. Previo u. s breeding cnon s with this impo na ll t food ya m species ha ve b('cn co nstrain ed b y : • Poo r sy nc hron iza lio n of flowering p(Ti od s or ea rly Illalt and late female pl a nls. plus a ge nerall y lo w il1l('nsil Y of flowering among parcntal cionl.'s. • A lon g vegclative ph'ls(' fro m secd glTminat io n lO f1 uwc.:ring co upled with a lo ng secd fo rmatio n period so that th (' secds had LO 1113 tU I\"{' under unf;\\\\'orab ly dry seaso n condit io ns. • Breedin g c10ncs large ly susceptible to tear necrosis. resulting in cO lnplt:te die bac k bt'-Ian: flowcring. ~ la ture seeds rro m croSS{'S betwee n nu Inc ro us Wa lCl\" ya m pa r(' nlCll clo nes were grown in nursery beds in th e 1 98•~ season. a nd resu lting tu be rs n:pla nrcd in th e fi eld in 1985 . Or56 c lo nt's tes tl'dthere. 12 wi t h accl'pta bIt t 1I bel' shl! pes a nd yields \"' line se lec ted. \\\"' hen sco red fo r disease reaction 10 the mos t impo rtant pa thogens o f wa leI' ya m {shOOl necrosis and vir us} lh eir perform ance was promising.\" ' ilh funher ge neti c reco mbina ti o n rro ln crosses using th ese Ill'W clones rrom seeds. th l' reWater ya Hl breed ing clo w ith d esirab tube r co nfonl1utio1 is now a g retl l('I' pOIl'nti nl II)!' \\\\'aler ya m im pro\\'(' mcnt by illco rpo ra ling necros is res istanc and profusc flo wering charac Lt \"Ts. Also. th l'S ac hi eve m ent!'! will permit int e rn a ti o nal l'X c hange ofw31cr ya m ge netic stocks in sl'('d fo rm -a n opporlllnil y whi ch did no t ('x isl befon•. "},{"text":"* Average of 16 replicaliolls. "},{"text":"July  "},{"text":"C onsumers in West Africa consider the sweet taste in sweet potatoes an undesirabl characteristic and prefer non-sweet varieties called staple sweet potatoes. Stapl lines in UTA's germplasm collection, consisting of almost 600 clones, have bee selected by determining total soluble sugar and reducing sugar concentrations in the flou prepared from raw and baked tubers. "},{"text":" Fift y-nin e more lin cs in th e coll cctio n were id cmifi ed as nOIl-sw('l't. A few, such as 'r IS 8267 a nd TIS 9 19 1, did not show an in crcase in suga r cOIlCl' ntra ti o n ann baking , slIgg<'s ting abse ncc o f a m ylase acti vit y. I n a preliminary lasu\" pa nel ('va lu a tion o f baked and boi!t:d SWt'l' t po ta tocs, Ihe lin e TIS 8504 wilh a li'cs h rool yield or 23.6 tl ha was never rat ed swee t. M o rc breeding work usin g no n-swcet till l's produce SWl' ct potatoes similar to white ya m deg ree of SW(.'l' tn ess, texture. a nd colo r w increasl' till' pOl('l1(i a l o f this luber c rop as sta ple food in \\• V{'st Afri ca.Tot a l so luble suga rs (°0) "},{"text":"E xperiments show that a combination of several methods are necessary if weevils (Cylas spp. ) -the most destructive pests of s weet potatoes both in the fi eld and in storage -are t o be controlled effectively. No single m ethod has a cco mplished this. Studi es of indi vidu a l contro l ((-c hniqu cs ha vl~ shown t ha t so mc im proved sweTt potato va rieti es sustain less weevil damage in th e fi eld tha n no n-im proved o n('s. Ea rl y p la nti ng a nd ha rves ti ng a rc a lso impo rt a n t beca use th e \\vceviis a re d r y S('~lso n pests a nd th eir popula ti on b u ilds lip o nl y during tha t peri od o f the yea r. Furthermore, th e weev ils loca t(, a nd d a mage the crop b y fo llowing cra cks in th e soi l around grow in g tu bers. Ea nhin g u p th e pia 11ls o r p lacin g a n additi on a l la ye r o f so il o n th e rid ge (IT-ridgin g) ma kes it difficult for th e weevils to loca te th e tubers.Aft er the har ves t, pUlling the swee t po tatOes in und erg round storage ad vlTse ly a ffcc LS weev il d evel op mCIll, a nd putting plalll ma teria ls wilh insec ti c id a l o r insec t repe ll en t pro p erli es in und ergroun d stOrage p its may further redu ce weevil d a m age.One phase o f a n exp erim en t to co ll ect dat a fo r the d evcio pmcIH o f a n in tegra ted weevil ma nage ment prog ra m in vo lved two improved swee t pO la to lin es w ith mod erat e resista nce to th e weevils (T I S 2532 a nd T IS 70357) a nd a loca l susce pti ble one (Tlb II ) . T he)' we repl a n ted inJun e (ea rl y plan ting ) a nd Se pte mber (la te pl a nting ) a nd ha rves ted in O ctober a nd D ece m ber. At ha r ves t time record s werc kep t o f tht\" number of pl a nts w ith d a maged tubers (hill 122 A co,nbination 0/ control rneasures are needed to reduce weev il dantage to s w ee t potatoes ; s how n he \"e is an e nlarged close-up a/the weev il lind its damage . infes ta ti o n ), weev il feedin g ho les o n tu be rs, th e number o f weevils, a nd th e number o r tubers w hi c h wou ld nOt b e ma rke ted beca use of weevil da m age. "},{"text":". Close linkages aJ-efoste red be twee n personnel £llllTA 's In te,-,zat£ona l Cooperation and Tra£ning Progr a1n and representatives of nationa l prog,-ams_ (One group £s show n he ,-e o n afield trip.) 1 ~a ti o n a l R OOl C rops l lllprove lll cll t Progra m lor ano th er three yea rs. "},{"text":" Assistan.ce to Ghana in 1985 mad r it poss ible for scientists there LO streng then the c leg ume breeding program lo r the development of specifi c high yielding vari e ti es of co a nd soy bea ns. Activities in Kenya were d esigned to streng the n colla boratio n \",ri th the I ntern Centre fo r Insect Ph ysiologv a nd Ecologv P CIPE) a nd to complem ent its research a nd thost'of lfT'A in th e areas of cowpea improvement and intcgra tcd pest ma nage m IITA intensified its efforts in Niger in th e id entifi cation, sti ecLion, a nd tes Ling o f c c ulti vars suitab le for mill ct-based cropping syste ms fo r the Sa hel ia n region o f Africa . "},{"text":" On e o f th e mos t co mpre hensive and long-running tra ining progra ms for assisting th development of nati onal ma npower ca pab ili ties is in Za ire. O ve r the past 10 yca rs, ITTA systematica ll y o rgani zed a nd deli ve red tra ining se rvices that ha ve ensured the es ta blishmen ofa full-fl ed ged Zaire Nati ona l Cassava Program. A tota l o f 153 Zaire na ti ona ls at va riou Irve ls a nd in various disc4) lin es received training. Notable a mong these a rc 19 M.Sc and 1 Ph .D. degree holders who have now ass umed res ponsibilities for leadership In a maj or natio nal thrust in cassava production. More complete information on the topics mentione d in this Executive Summary can be obtained by re ques ting the Annual Report of the International Cooperati on and Training Prog ram. "},{"text":" scicnLific info rmatio n a mo ng th e interna tion a l centers. During 1985, a new computerized mailing list was developed using BASIS. The old compuler progra m was limited and clumsy to usc. The new mailing list database can be searched via numerous categori es: [or example, by name ,job title, discipline, orga niza Li oll , publication (s) required , la nguage, a nd subj ects of interest. All entries in the ma iling list were indi vidua ll y chcckcd a nd corrected as necessary. Altho ug h so me add resses were dropped , th e re was a nc t in crease of abollt 600 eluring 1985, bring in g th e tOl a l to 4,600. M os t o f th e additions were libra ries to facilit a te the imple mentation of a Deposit Libra ry Scheme in whic h libraries of key institutions in Africa and donor countries arc designated IITA D eposit Libra ries. They receive a ll IITA pub lica ti ons gratis and a re requ ested to ma ke them readil y available to anyone seekin g information abou t the I nstitutc's work . Publications produced during the year includ ed: IITA Annual Report 1984; llT A Research Highlights 1984; Le Point de la Recherche 1984; Varietal 1mprovement oj Cowpea/ L'ameiioration varietale dll niebe (C rop P roduction Training Seri es No. I) ; T ropical Root Crops: T heir Improvement and Utilization; A Bibliograph), of rams ill the Genus Dioscorea, vol. 2, 1975-1983; A Case Study ~f On-Farm Adaptive Research in Bida Agricultural Development Project (OFR Bulletin No. I) ; a nd Report on Exploratory Survey of !jarye IlIZini Pilot Reseanh Area , Oyo State, Nigeria (OFR Bulletin No. 2). R eprints of the Research Highlights for 1981 -1984 were compiled a nd published for each of the fi ve research progra ms. The audiovisual staffinitiated video recordings of Institu te activi ties a nd produced an entirely new 17-minu te , three-proj ector audio/slid e' presenta tion giving an overview of th e Institute's researc h and training acti vities. M ass media coverage of IITA 's work (particularly thro ugh newspapers a nd magazin es) was frequent a nd wid espread during 1985. R esearch accomplishments were displayed at a week-long Farm T ech '85 Exhibition in Kingstoll , J amaica. More than 20,000 visitors, including J a maica's Prime Minister, toured the lITA exhibit. The Institute was a lso represented a t both the Zimbabwe a nd Fra nkfurt Book Fa irs. "},{"text":" Sem.inars were conducted fa r va ri o us audiences in N igeri a a nd at the Uni versit y of Bon in \\,Vcs t Germa ny a nd the I ntcrna Liona l Deve lopment R esea rch Centre in Onawa , Ca nad a nd sta ffm cm bers colla bora ted with scien tists to organi ze many field d ays \"on-site\", as we as at variolls loca tions off-ca mpus. These (-ield d ays a ttractcd thousands offarmcrs, ex tensio workers, gove rnment orTicials, a nd resea rchers or o ther institutions. Two open-house da hrld on the ca mpus a ttracted members o f' the Nigerian C ha mber of Commerce a nd i di vidua l prospecti vl' in ves tors in agri c ultulT.Virology UnitV irology research in 1985 focused on the etiology of unknown d iseases, refining ind exing techniques, resistance screening, studies on pathogenic variabi lity, and ecology of viruses. To faci litate control of virus diseases causing economic losses in crops under inves tiga tion at IITA, virologists continu ed studies on virus diseases in cassava, yams, sweet potatoes, cocoyams, cowpeas, soybeans, rice, and maize. They collaborated with pa thologists, breed ers, and entomologists of crop improvement programs to screen for resistance against importan t virus diseases. "},{"text":" Sllm.tnary can be obtained by requesting the Annual Report of the Virology Unit.Genetic Resources Unit P iant explora ti on and a cquisiti on acti vities cOillinucd during the yea r 'with 42 1 sample of scccis of\" cowpcas, ri ce, and o ther c rops collected in the Centra l African Republic and add ed to liT A's la rge gcrmpias rn \" ha nk. n I n this a nd O(h e1' collection expeditions, I h Institute secks o ut bo th culti\\\"ated a nd wild species ,,\"hi ch become the source of geneti di\\-c rsity lIsed by scientists to d evelop new insL'c I-a nd d isease-resista nt a nd high yieldin va ri e ti es. Na tion a l progra ms a nd l iT/\\, 's n'sl'a rc hcrs provided a no ther 502 sa mples in 1985 Part of the \" bank's \" stock -12,497 samples -was sent to 29 countries ror liSt' in thei pla nt breed ing progra ms, a nd during lh l' year sn Tra i thousa nd gcrmpl as m acc('ssio ns wer g rown at rITA 's headquarters ror seed in clT<1se or rejun'nation. The sta ff a lso d ocumente d a ta o n morpho logica l and agrono mi c cha rac teristics a nd other f~t c LOrs for ma rc tha n 3,00 accessions, a nd this process continlH:s, as d oes upda ting of the gl'rmplas m informa tion b computer. Th ese d a ta speed up the ra te ofscicntists' findin g of specific genetic ma teri a ls the want fo r their resea rc h. "},{"text":"Table 1 . Dry  "},{"text":"Table 2 . Ef  "},{"text":"Table 3 . Per  G round G round  covel\" covel\" Lcgurnillous spccies ((1 0) Lcgurnillous spccies((1 0)  87.5 87.5  61.3 61.3  52.5 52.5 Sl'shllllia srshml 16.3 Sl'shllllia srshml16.3  "},{"text":" , AFG RAD progr;•lm, two vcrsio ns of the ti cridging impknwlll ,,'tTl' cit:signl..\"d one lor d o nk cy POWCL th e.' ot her fOI'oxt'n, Thl' desig n is based o n a \" tripping shove l d c'v ice ' by Lyle and Dixon, I t has four flat shO\\,t!s that roll o n an ax is, The ro lling is controlit'd by a calch mec hanism th at is activated by a bi cycle break I('vl'l\"  on th e handle o f th c rid geI', \\\\' hen th e dl..'\\'icl' is attached behind a ridger, o ne of t11l' sho\\'(.' ls pulls loose soil a long the' furrow ullti l the.' OptT::ltor relc-ases Ihe catc h mechanism, \\Vhen hc d ol'S this. thc ncxt s ho\\'cl ro lls on'l\" and the process begins aga in,The donke y model wh ich weig hs II kg has -+0 CI11 wid e shovels a t th e base, tap erin g to 16 c m a t the o utsid e, (Comparabk fi g ures lo r the oxe n model : 17 kg, 55 em , and 20 c m,  "},{"text":" Agricole manll(~I C tlll'(' d 75 d O ll kt,~ and 60 oxe n models for Ihe eos l o f materials and l:lbor. Sc\\'{'ral research institutions (lC R ISAT, FSR-SAFG RAD . IRAT-C IR AD. \"nd .he II'orld Bank Pilo t Pr~j(,cl for .\\ gric uitura l Dn'ciop-mCIH ) are co ndu ctillg indepl'nd,•nl I'c!H'tll\"ch a nd !cs lin g Wil h 36 d o nk('Y and ~ll oxe n m od~' ls , and sc\\'cn dn'e!opml'nt o rga ni za ti ons a n ' The Cl'IlII'{' Nalionak-d ' Equipt'mt'nl The Cl'IlII'{'Nalionak-d ' Equipt'mt'nl t(,\"' ling 30 d o nk cy ,lI1d S('\\'('n oxel1 mod els in t(,\"' ling 30 d o nk cy ,lI1d S('\\'('n oxel1 mod els in coopna ti o n with fa rm ers fro m 15 \\'illagl's coopna ti o n with fa rm ers fro m 15 \\'illagl's within a 60 km radius of Ouaga d o ugou, A within a 60 km radius of Ouaga d o ugou, A majority ofl h(' participa ting fannlTs an' in th e majority ofl h(' participa ting fannlTs an' in th e PrOj(,C L d l' ValoriS::ltion d es Sill'S .\\n ti -Ermi[;,; PrOj(,C L d l' ValoriS::ltion d es Sill'S .\\n ti -Ermi[;,; co ndu ctcd by Fonds de rEau lot Equipl'lllt•nt co ndu ctcd by Fonds de rEau lot Equipl'lllt•nt Ru nde FEER )'  Ru nde FEER )' Preliminary tCStS showed that til(' d o nk ey Preliminary tCStS showed that til(' d o nk ey model could m a ke 13 e m (\\(ocp li ed ridges in model could m a ke 13 e m (\\(ocp li ed ridges in rows 50 em a part and the oxe n model 16 c m rows 50 em a part and the oxe n model 16 c m d l'e p tied ridges in rowS 70--80 el11 apart. Once d l'e p tied ridges in rowS 70--80 el11 apart. Once thl' ridges a1\"l: made. it takes tilt' f ~lI'mcr abo ut 72 thl' ridges a1\"l: made. it takes tilt' f ~lI'mcr abo ut 72 mun-hours pLT hec tare to prepare li cs b ~ hane\\. mun-hours pLT hec tare to prepare li cs b ~ hane\\. This tinll\" is red uced to 32 m ~lI1-hours by lIsing This tinll\" is red uced to 32 m ~lI1-hours by lIsing th e d o nkey ri dge-ril' r model. th e d o nkey ri dge-ril' r model.  "},{"text":" ers pla lll so rg hum, mi llct, ground nUl ma ize, and melons oft en u nd er illlercro sys tems. Ra infa ll d istri bu Li on and a fa rmer crop calenda r a re shown in Figu re 2.  7 7  7 7  7 7  Rice Rice  Rice Rice  Rice Rice  Rice Rice 300 f-  300 f- 200 f-  200 f- • • 0 1 .. • • • • 0 1 ..• •  "},{"text":" Nige ria. H edge rows were succcss(u ll y esta blished by lra nspla nting 2~ l11o nth-o ld seedlings rro m plots w here th ey were g rown in associat io n with ma iz e a nd cow peas o n sa nd y a nd d egraded land infes ted with the noxi o us weed Im/Jernla c),lilldriw.    A lley c t\"opping w ith two w oody s p ec ies  A lley c t\"opping w ith two w oody s p ec ies    1...eIl((Ulln and (;liricidin and cowp ea s on a  1...eIl((Ulln and (;liricidin and cowp ea s on a    degraded Entisol iPi the deriv e d savmwa of  degraded Entisol iPi the deriv e d savmwa of    southe rn Nigeria.    southe rn Nigeria. Maize groin yield ( kg/ ho )       Maize groin yield ( kg/ ho )  LSD(5 %)       LSD(5 %) 4.0        4.0     Fig ure 3. Effec t of long -  Fig ure 3. Effec t of long -     term alley c \" opping w ith  term alley c \" opping w ith 3.0    four weedy species and tlitp'ogen rates o u grain  3.0four weedy species and tlitp'ogen rates o u grain   Dr} matter  yield of pna ize v arie tJI  Dr} matteryield of pna ize v arie tJI 2.0 Specit.' S pruninb\"S (t fhtt /Yl'a r ) N TZPB g row n ItIlder no NU lrielll yidd (kg/ haht•a r P K C:I t illage in d eg raded i\\ lg 2.0Specit.' Spruninb\"S (t fhtt /Yl'a r )NTZPB g row n ItIlder no NU lrielll yidd (kg/ haht•a r P K C:I t illage in d eg radedi\\ lg  Acioa barli'rii AIr/IOn/tO rordijolia 3.0 '.0 40.5 8\"-8 3.6 Alfiso l ;fifth c ropping 20A-14.7 6.4 48.0 41.6 year. SA 8.0 Acioa barli'rii AIr/IOn/tO rordijolia3.0 '.040.5 8\"-83.6 Alfiso l ;fifth c ropping 20A-14.7 6.4 48.0 41.6 year.SA 8.0 1. 0 (.'liriridia Ji'/ lIIlIIl 5.5 169.4 1 1.0 11 9.1 66.0 17.6 1. 0(.'liriridia Ji'/ lIIlIIl5.5169.41 1.011 9.166.017.6  UlIrfltlla Ii'uroaphala 7.4 :247.2 19.9 185.0 98.1 16.3 UlIrfltlla Ii'uroaphala7.4:247.219.9185.098.116.3 o        o  "},{"text":"Table 6 . On 31.500 2+.300 33.200 25.700 31.5002+.30033.20025.700 19.300 16.800 22.000 18. 100 19.30016.80022.00018. 100 62 69 Gi, 71 6269Gi,71 .UB .065 .Uij .065 .UB.065.Uij.065 1,5;}() 1.090 I. 7{')(\\ 1.180 1,5;}()1.090I. 7{')(\\1.180  "},{"text":"Table 8 . PercolatioPlJprofile  "},{"text":"Table 9 . Runoff   Yidd tl ha Yidd tl ha   Grain 511\";1\\\\ Grain511\";1\\\\ Rict, Soil .11 11\"0 on'n Rict,Soil.11 11\"0on'n   2.0 1.2 2.01.2  BunH'd :UJ 4.7 BunH'd:UJ4.7 ISA6 :'\\01 bunH'd 2.0 3.3 ISA6:'\\01 bunH'd2.03.3  Hurtll'ci 2.6 3.B Hurtll'ci2.63.B ITA 11« ~ot bunwd 1.5 2.h ITA 11«~ot bunwd1.52.h IR 52 \\;01 hunl('d 0 . .5 2.u IR 52\\;01 hunl('d0 . .52.u  "},{"text":"Table 12 . Number of plantain sucke ,'s produced per stool in ,-esponse to different  "},{"text":"Table 13 , Yie l00Sn•d l00Sn•d weighl weighl 11 11 21 21 20 20 III III 1:2 1:2 13 13  "},{"text":"Table 16 , Reaction  "},{"text":"Table 19 , Perforrnance of cowpea line CNCx 252-1E  "},{"text":"Table 24 . G r'ai\" yie ld 2.7 I.Q-IA 2.7I.Q-IA 1. 6 0.5 3.3 1. 60.5 3.3  "},{"text":"Table 25 . Damage  "},{"text":"Table 26 . Maize varieties and parental populations being converted to streak resistance.  "},{"text":"Table 27 . Yie ld and streak resistance level of four maize streak resistant (SR) materials(1985).  "},{"text":"Table 28 . Stalk  "},{"text":"Table 29 . Summary  "},{"text":"Table 32 . Performance  "},{"text":"Table 33 . Perfo  "},{"text":"Table 34 . Grai\" yie ld oj  No lIitrogl'n 60 kg N/ha  No lIitrogl'n60 kg N/ha St'~hania cuuings C rain r idd Yield incn•:L' >I' Gra in yidd Yidd increase rice v(H'iety ITA 306 St'~hania cuuingsC rain r iddYield incn•:L' >I'Gra in yiddYidd increaserice v(H'iety ITA 306 (t/ha l (kg/ha) (°0 ) (kg/ha) (o {))  (t/ha l(kg/ha)(°0 )(kg/ha)(o {)) 2 4.327 42. 1 •1.645 3.80  24.32742. 1•1.6453.80  "},{"text":"Table 38 . Ware yam yield yam yield with and without plastic with and without plastic mulch; different times of mulch; different times of planting and Nove mber planting and Nove mber harvest. harvest.  "},{"text":"Table 39 . Ware y am. production using alternative m.anagem.ent m et hods.-cos ts and income (Nigerian Naira).  "},{"text":"Table 40 . Memt y ie ld and stability index oj elite sweet potato lines tested in six environments in Rwanda .  : ' -o lean  : ' -o lean  yield Rcgn:ssion yieldRcgn:ssion Line «/hal coefficient Line«/hal coefficient DV 16/820 12.8 1.28 DV 16/82012.81.28 T IS 2544- 9.6 1.3i T IS 2544-9.61.3i Serura 9.3 1.02 Serura9.31.02 Rutam bir:t 9.2 .96 Rutam bir:t9.2.96 Bukarasa 812 9.1 1.00 Bukarasa 8129.11.00 \\Vadada 7.6 .91 \\Vadada7.6.91 Rcscnya (loca l check) 6.3 .71 Rcscnya (loca l check)6.3.71 N),jra muju na 5.1 . i I N),jra muju na5.1. i I ~I ean 8.6  ~I ean8.6 SE 2.3  SE2.3  "},{"text":"Table 41 , Yield an.d total Non-Swat Non-Swat  "}],"sieverID":"a1783c60-377c-4b35-9607-95701ce7a76a","abstract":"A t the initia ti ve of the Wo rld Ba nk, the United Nations Food and Agriculture O rganiza tion (FAa), a nd the U nitcd Na tions Development Progra mme (U. DP), a n info rmal associa tion of governm ents, internatio nal and regiona l organizations, and private fo undatio ns was set up in 197 1 dedicatcd to supporting a sys te m o f agri culLUra l resea rc h centers around the world. II was na m ed the Consultative Group o n In ternational"}
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