Cover Crops for Natural Resource Management in West Africa (Book 5) by International Institute of Tropical Agriculture

Countryandnefwork repomlRapporlsnationauyet du lieseau 251

Tableau 3. Semences de plantes de ccuveriure disiribuees aux utiliiateurspoientieis en 1999. Producieurs ONGs Chercheurs Projet de Especes P I P2 P3 P4 0 1 02 0 3 CH9 CH2 dbeloppement -

C. ochroleuw S. rostrata Mucuna spp. Rajada Mucuna spp. Nagaland iWucuna spp. Ghana Mucuna cochinchinensis

x X

x x

NB: Les quantitk de semences distribuees par individu vont de quelques grammes a 1 kg selon la disponibiliie du produit.

Les semences sont distribdes aux paysans. Dans le Bassin Arachidier, 170 graines de Canavalia ensiformis,990 graines de Munrna spp. Rajada, 385 graines de Mvcvna cochinchinemis, et 125 p i n e s de DoIichos lablab sont pattagees enire les quatre paysans. En Moyenne Casamance, 40 graines de C. ensformis, 100 graines de Mucuna spp. Rajada, 80 p i n e s de Mucuna cochinchinensis, et 60 graines de Dolichos iabiab sont domdes au paysan de Marsassourn. Les tests sont effectuds sur des sols argilo sableux appelC Deck Dior au Centre et sur des sols argilo iimoneux au Sud. Les dcattements de semis sont 1 m sur Ia ligne et 1 rn e m les lipes a raison d'une A deux graines par poquet selon la grosseur de la graine. Dans les deux sites seules les espkces Mumu spp. Rajada et Doiichos iablab ont produit des graines. Mucuna spp. Rajada a fourni au Centre et au Sud du pays 1.200 kg et 2200 &. Doiichus Iabiab a produit respectivement au Centre et au Sud 0.300 kg et 0.200 kg. Les rendernents obtenus sont tres faibles surtout au Centre ou les pluies se soni hstallees tardivement. La divagation des animaux (petits ruminants au Centre et les boeufs au Snd) non con@6lbea fortement perturb6 ie developpement des cultures. Les cultures de Cunavaliaens@otjnis et Muma cochinchinemisen pleine floraison au sud, ont e d complkiernent brout4es par les baeufs. Les contrahies majeures renconbks en milieu paysan pour fe ddveloppement des cultures de couvertwe sont une saison des pluies incertaine (installation tardive, repartition non homog6ne, courte d d e ) , divagation des animaux. Des artaques d'insectes sont notees dans les cultures et les paysans sollicitent une aide en produiis phytosanihires. D'autre part les paysans s'interrogent sur l'avenir de M u m a et ses d~bouchbdans le mmhd. Pour la campage 1999, M. Dieme a pu mgmenter son CchantiIlon de paysans pilotes. II a =ens& au Centre du pays huit paysans et au Sud guatre paysans en attendant de recevoir des semences supplkmenwims. Les semences disponibles sont dejh distribuies.

252 Cover cmps fur natural resource managernenWlantesderouverture et gesiion 6ssr e m e s nalureflss

Propositiond'un projet de recherch~6el~ppernent Dans le but d'assurer la sCcuritC alimentaire des populations ntrales de la zone des Niayes par le maintien de la fertilite de leurs ptrimttres maraichers, une proposition de recherche-devzloppement intitult 'WGet de la culture de Mumna sur la fertilitd et sur I'infestation des sols en nematodes phyloparasites dans la zones des Niayes (SCnCgal)" a Cte Clabort par I'ISRA et soumis pour financement au CRDI. L'objectif gCnCral du projet est i'am6lioration de la productivird des systhes de culture maraicheres de la zone des Niayes par la culture de Mucuna. Cet objectif est sous tendu par trois objectifs specifiques qui visent A impliquer les agriculteun dans la mise au point et la diffision de ['innovation technologique, A amkliorer I'Ctat de fertilite des sols de la zone en vue de relever la productivitC agricole et a diminuer I'incidence de I'infestation des sols par les nematodes phytoparasites sur les cultures. La durke du projet est de quatre ans avec deux cultures de Mucuna en jachtre amelioree les deux premikres annees. Chaque culture de Mz4cuna est suivie d'une culture maraichere pour tvaluer I'effet de la jachere. La troisieme annee, la culhue de Muczrna ne sera pas egectuee, seules les cultures maraicheres seront mises en place B la mCme ptriode de I'annCe pour etudier I'arriere effet des cultures de Mucuna. Des prkl2vernents de sols et de plantes seront effeciues pour suivre l'kvolution de la population des nematodes sous les cultures. Les travaux sur le terrain dtmarreront avec un diagnostic pariicipatif du milieu par la Mkthode AccelCrke de Recherche Participative (MAW). Le projet est soumis pour financement au CRDI qui a dome un avis favorable aprb une premitre ktude. L'Ctude dCtailKe du projet est en cours au CRDI.

Les activitis conduites dans le cadre du ClEPCA ont permis de degager les conclusions ci-apr*s: Bonne initiation des activirds relatives 9 la diffision des plantes de couveme Sensibilisation des acteun de la recherche44veloppementet des baiHeurs de fonds sur I'importance des plantes de couvertures dans I'amClioration de la fertilitk des sots L'implication des utilisateuis (ONGS,producteurs) dans les activies de recherche dtveloppement. II s'agit maintenant de: Consolider les acquis par tous les intewenants Vulgariser A moyen teme e t a grande Cchelle I'utilisatiion des plams de couverbm initier des experiences d'adaptabilite d'espkces de- plantes de couverture pour chaque zone Ccologique.

Country and neiwork mporldRappwts nationawe?clu rbseau 253

Toutefois, quelques contraintes ont ite identifiCes (suivi sur ie terrain des semences distribdes, contact des acteurs du ddveloppement) pour lesguelles il est nkessaire pour la suite des activitds de CIEFCA de trouver des solutions approprides.

Habas. 1965. Le StizoIobium comme e s p h ameliorate de la jachere. Page 391 dum Sols Africains. Vol. X No2 et 3, OUAISTRC.

Activitks li6es 6 I'utilisation des legurnineuses herbacees au Mali-sud

DivisionD@kmet Resi~tondesSoWCompngnieM(~Iiermep~urIe~Ioppen!mfdes TextiIes. K~rrriofe Mati

Le rtile des Epnineuses herbades devient de plus en plus important en zone CMDT pour contribuer I 1'amClioration de la fedlitk des sols mais aussi a l'alimentation du bkail qui constitue m e cornposante indispensable au maintien du potentiel productif des terres cultivdes. ZRS 14gi.mineuses herbackes en m e CMDT sont cultivkes b travers des soles fomag8res pluri-mueelles avec S@losan?heshmda ou AescPlynomene kbtrk: et la culture fomag&e associde maiSaotique ou ni4bkhkaIes. Les systhes basks sur les IkgumheusesA mines (Doiichos lablab et Vigna anpiwlata) sont beaucoup plus adopt& que les soles plurimuelbs B base de ltsgumineuses StTictement fomgims. La superficie des soles pluria3]nuellesde Sfylmandheshamafa ou Aeschyaomene histrix implant4e chaque m 4 e est estimee 108 ha. Les semences de Sylosantkes hamafa sont produites I la ferme CMDT de Dalabani suite B m e forte ddgradation du sol par des c u k e s annuelles.

The role of herbaceous legumes is gaining importance in the CMDT zone in terns of soil f d l i t y improvement and fodder production which represent an essential component in the preservation of the productive potential of cultivated lands. In the CMDT zone, herbaceous legumes are produced with p l w k m u l plots of fodder crops Sfyfosanthes hamara or Aesctrynomene hisirk and the association of rnaiz+Dohoh fabdab or cowpea-cereak. Grain legume based systems (DoEichm fablab and Agna unguimiata) are better adapted than strictly pluFimua1 fodder legume plots. TRe Siy/osanSheshamafa or Aesc@nomene histrk pluriannual plots covered every year an area of 100h a Sfyiosanthes hamata seeds are produced at the CMDT farm in Dalabani following serious soil degradation by annual crops.

Cauntrjf and network repods/Rappartsnationauu st du &eau 255

Prbentatian du CMDT ef la tone La Cornpagnie Malieme pour le Dkveloppement des Textiles (CMDT)est une entreprise agro-industrielle de transformation et de commercialisation de la production cotonni5re (Fig-l); elle couvre une superficie de 151 050 IanZet la population concernde atteint 2.2 millions d'habitants. La CMDT encadre 170 690 exploitations agricoles dans 5400 villages et hameaux et est chargde de la mise en oeuvre du dkveloppement ma! intkgr.5 bask essentiellement sur les sys&mes de production du coton. La pmduction du coton-graine a atteint les 522 000 tonnes en 199711998. L'objectif est de produire le coton dans le cadre d'une diversification et d'une rotation agronorniquement et Bconomiquement equilib&. Le coton ne dkpasse pas 24% des superficies cu!tivdes. Les autres productions pour la campagne agricole 1997f 1998 sont: mais 392 799 tonnes; mil-sogho: 581 628 tonnes; riz: 90 643 tonnes; nidbe 44 345 tomes; arachide: 58 780 tonnes; ddx 652 tonnes; soja: 523 tonnes; fonio: 10 165 tonnes. Les rendements du wton tournent autour de 1100 a 1200 kgha. Le r5le des Ikgumineuses herbacdes devient de plus en pIus dkterminant en zone CMDT pour contribuer a I'dlioration de la fertilitk des sols mais aussi B l'alirnentation du betail qui constitue w e composante indispensable au maintien du potentiel productif des terres cultivkes. Les doses d'engrais utilisdes par les paysans sont encore en dessous de ce1les recommanddes par Ia CMDT.

Mali

Figure 1. Carte de la zone CMDT au Mali-sud.

256 Covercrops fornahrralresourcemanagemenPlantesde cowemre et geslion des ressourcesnaiurelles

Dbcription dm sysgmes de IQgumineusesherbac4es Les legumineuses herbactes en zone CMDT sont cultivt5es i~travers des soles fourrageres pluri-annuelles avec StyIosanthes hamara ou Aeschynomene histrix (Fig. 2) et la culture fourragere associCe maiis-dolique (DuIichos 1abIab) ou niibC (Kgna xmngaic~fl~fa)-cCrCales (Fig. 3). La sole fourrag6re pluriannuelle est une parcelle librement choisie par I'agriculteur pour la culture perenne de l6gumineuses qui produisent du fourrage et arnkliorent la fertilitt des sols. Les soles fourrageres pluriannuelles peuvent Stre r4alisCes sur les parcelles moins fertiles ou B mettre en jachere. L'insertion de la sole fourrag&redans I'assolement/rotation de I'exploitation est un objectif l atteindre. Les soles fourrag&es pluriannuelles viennent rarement en tete de rotation. Le semis en premiere annee (StyIosan&h&hamam, Aeschynomene hisfrrjc) doit s'effectuer avant la deuxierne decade d'aoiit pour assurer le resemis en deuxieme annte. L'utilisation du phosphate nature1 est recornmandie pour pallier a m carences en phosphore des sols.

Utilisation des syst6mes de l6gumineuses herbac6es Les donnees dans les Tableaux 1 et 2 monwent que les syst2rnes bases sur les legumineuses 8 graines sont beaucoup pbs adopt& que les soles pluriannuelles A base

Figure 2 Sale fourragim (Stytosanthes hamafa ou Aeschynomene h i m ) de Xmls am avec kcolhe de fourrage et graines.

J Figurn

Culture foumgBre associbe marsldoliqus [dolichrrs lablab) ou ni6M (Mpns

unguiw~ata).

Countryand network repoiWRapportsnationam et du &eau 957

Tableau 1. Estimation du nombre de paysans qui ont test6 le sysieme dans la zone CMDT : Campagne agriwle avrit 1996 a mars 1997. Systerne

SuperfIcie (ha)

Sole fourra@re pluriannuelles Avec S.hamata ou A. fristrix Cultures fourrageres pures Doligue ou niebe Cultures fourrageres associees Maisisldoliqueou mavslniebe

Villages

Exploitations

194

327

20.971

1705

9.814

24.986

2.306

9.738

Oolique = Dolichos lablab;nieb& = Wgna unguiculata.

Tableau 2. Estimation du nombre de paysans qui ont teste le systltme dans la zone CMDT: Campagne agricale avril1997 a mars 1998. Systeme

Supeficie (ha)

Sole iourrag8repluriannuelles Avec S. hamata ou A. histrix Cultures iourragerespures Dolique ou niebe Cultures burrageres associees Maisldolique ou ma'islniebe

Villages

Exploitations

5.143

1.196

8.984

8.822

'1.380

7.904

Dolique = DoliGhos labtab; ni8b6 = Wgna unguiculata.

Tableau 3. Production des semences de cufturesiourrageresen lrois campagnes agrimlessur la ferme de CMDT B Dalabani.

Stylosanthes hamata Panicurn maximum C1 Panicum maximum T58

1996197

1997198

199WQ9

31 50 455

2200

1675

a 5

115

1200 18

Tableau 4. Pouvoir germinatif des reliquats de stock de StyIosantheshamate en 1998. Annee

Taux de germination (%)

de Sty~osantheshawrata ou Aeschynomene hist~ix.Lvadoptiondes sole pluriannuelles est plus importante cSans les rigions de Koutiala, Fan& et Sikasso. En 1999, 54 parcelles fourrageres ont 6t6 installdes a Molobala (Region de Koutiala) avec m e superiicie de 65 ha. Un programme d'inskmination artificielle entrepris par la CMDT en 1999 a perrnis a Molobala dvaugmenterla rdalisation des soles fomgeres avec S@!osantheshamam. Onze exploitations agricoles ont rdalise ainsi la sole fourragere

258 Cover crops (arnahrml resome managementPlentes de couvemre et gestion des resources nahlrelles

en vue d'amtliorer I'alimentation des animaux retenus dans le programme d'insdmination artificiel. Signalons aussi que I'augmentation des rdalisations P Molobala s'explique par la prksence d'une mini laiterie A Koutiala approvisionnke par les exploitations agricoles de Molobala. Un programme de jach&reamCliorke est aussi entrepris par la recherche (l'lnstitut d'Economie Rurale: Programme Ressources Forestieres) dans cerhins villages de Molobala et il coaceme les parcelles de Srylosanches hamala avec le Giiricidia comme h i e vive. L'objectif est de lutter contre la baisse de fertilitC des sols et amkliorer I'ktat nutritionnel des bovins. Les visites inter paysannes favorisent beaucoup I'adoption des soles fourrageres.

Frogrts &lisb dans la disponibilitk de semences de I6gumineuses herbacki Les sernences sont produites B la ferme sernencikre de la CMDT a Dalabani dans la Region CMDT de Bougouni. La ferme a it6 cr&e initialement pour la production des semences de riz, de dah, et de mais pour satisfaire les besoins des paysans. La feme est situde sur un versant i 1.5 kilometres d'un fleuve. Apres sept ans de production continue de semences les rendements ont baissC maigre la rdalisation des mesures de luae contre I'erosion hydrique (ambagernent de fosses au niveau des parcelles, rblisation de lignes en cailloux .ou ctcordons pierrem) en amont des parcelles, mitemat des rigojes et des ravines, haies vives). Suite h ces constats, la ddcision de m m e ces parcelles en jach2re amCliort5e a 6% prise en 1992. Les especes fomg2res SfyIosanthes hamata (accessions verano et CiAT 236)et Panicurn mmirnum (cultivars C1 et T58) ont kt6 introduites sur 88.2 hectares. Les productions pour quelques campawes agricoles sont disponibks dans le Tableau 3. Les taw de gemination des reliquats de stock de Sfyiosantkes hamata ont dtd r n e s d s en 1998 (Tableau 41.).La dm& de stockage entra"ure m e baisse des tawc de gemhation. ZRS semeilces sont stockdes dans m magasin couvert de tdes ondulbes. Des possibilMs de vente de semac-es existent car tom la production a ' & pas utilisbe.

260 Covercrops for natvrat resourn managemenVPlantes&comrture etgestion des ressouces naturelles

mtritent d'etre poursuivis. Des travaux de criblage de variktds sont rGalist5s d m les zones Ouest et Est du Burkina Faso. Ce travail a egalement conmenct5 en 1998 et se poursuit en 1999. Parmi les nombreuses especes testtes le Mamna cochifichinensisei Mucuna pmriem se sont rrJvt5lCes adaptees au contexte climatique. L'utilisation du MZCICIIU et de la dolique pour I'alimentation des animaux a tit6 initid a I'MERA avec cornme objectif, l'amtliorer la pmductivite en lait des vaches. Le programme d'ktude sur les plantes de couvemes est iises debuts au Burkina Faso et il rencontre un ineret reqquable sCrieux des producteurs qu'il faut maintenir et utiliser pour developper pour promouvoir leur adoption.

Abstract The introduction of cover crops in farming systems is quite recent in Burkina Faso. Some work has been already done on the topic. It still seems very premature to assess the situation and the likelihood of a successful development of cover crops in Burkina Faso. It would be necessary to carry out some activities before paving the way for a concerted development of such activities on cover crops. The cost and availability of seeds seem to be major constraints for farmers and a limiting factors in the adoption of cover crops. institutions like MERA are already involved in the promotion of cover mops. Seeds are distributed to farmers for multiplication and tests. Farmers are using legume cover crops for soil improvement and animal feed production. In Burkina Faso, there is no control body for locally produced seeds. Given the high demand for seeds and advice, it would be more appropriate to involve farmers from the beginning of experiments on seed production and storage techniques. Research activities were carried out on the integration of cover crops in farming systems and they need to be continued. Varieties were screened in the West and East of Burkina Faso. This work started in 2998 and was continued in 1999. Among several species tested, Mucltna cochinchinensis and Macuna pruriens turned out to be adapted to the climatic environment. Activities on the utilization of Mz~cunaand DoEicttos labjab as animal feed were initiated at INERA and the objective was to improve the production of dairy cows. Although the program on cover crops is still recent in Burkina Faso, interest among fanners for cover crops is tremendous and should be maintained and used for the development and promotion of their adoption.

Introduction L'agriculture du Burkina Faso est caractkrisie par sa faible productivitd. Les faibles rendements des cultures s'expliquent entre autres par les conditions pluviomt5triques ddfavorables, la pauvretC originelle des sols en Cltrnents nnurritifs, la faible utilisation des enpis minCraux et organiques. t'agriculture est du type extensif utilisant la

Country and network reporiskap~rtsnatiOMUx et du r&eau 261

jachtre comme moyen de restauration de la fertilitd des sols. La forte croissance demographique augmente la demande en terre entrainant une forte pression foncDre dont I'une des consdquences immediate est le un raccourcissement de la dude des jacheres qui etaient les moyens traditionnels de restauration et de maintien de la fertiliti des sols. Les facteurs de degradation des sols comme l'drosion, la baisse de la matitre organique, I'acidification sont de plus en plus acceniub. I1 devient impdrieux de divelopper des techniques accessibles aux producteurs pour I'aider a protkger les sols contre la degradation. Dans cette optique, les plantes de couverture offrent une alternative intkressante. Cutilisation des plantes de couverhlre peut permettre de protdger les sols contre I'Crosion, augmenter la biomasse et la matiere organique et amdiorer la productivitk des systemes de culture. Un programme de travail a 6td rCalis6 au Burkina Faso pour iniroduire et valoriser les plantes de couverture dans les systkmes de culture. Le prksent rapport fait le bilan des principates activitCs.

Caracieristiques agroclimatiques du BurMna Fasa Le Burkina Faso est un pays sahklien situk au caur de I'Afrique de I'Ouest. La superficie totale est de 274 200 krnz avec une population totale estirnte B environ 20 millions d'habitants par le recensement de 1998. Le pays cornporte trois zones climatiques. L'extrEme Nord du pays est ddsertique avec un climat du type sahetien semi-aride. La pluviomCtrie annuelte varie entre 300 et 600 mm.Le plateau central a un climat Nord soudannien avec une pluviomdtrie annuelle variant de 600 a 800 mm. La pmie Sud et Sud Oust a un climat du type sud-soudannien dont la pluviomdtrie annuelle varie entre 800 et 1200 mm. La population est essentiellement agricole avec environ 90% des actifs dans ce secteur. Cependant, seulement 113 du territoire est exploite par I'griculture. Comme dans tous les pays de la sous region, la croissance dtmographique est tres forte entrainant du mCme coup augmentation de la demande alimentaire et une forte pression sur les ressources en terre.

Progrtk d'adoption des syst6rne.s de culturn de cauvetture L'introduction des plantes de couverture dans les syst&mesculture est assez rdcente au Burkina Faso. Les experimentations ont bt6 surtout concentrdes dans la partie ouest du pays oB on trouve des conditions pedoclirnatiques assez favorables. Les pratiques pysannes de gestion de la fertit itd des sols consistaient en une mise en jach2re assez profongee. La restauration de la fertilite n'est realisee que lorsque certaines espkes dominent la strate herbacte. I1 s'agit principalement des andropogon&s qui sont en m&metemps tfts appr6ciQ par les animaux. Aussi cette graminke est utilde par les producteurs pour plusieurs besoins domestiques telles que la toiture de certaines rnaisons et hangar et la protection des aires de sdchage et de maraichage. Afin

262 Covermps fornatural fesommanagemenVPIantssdecwmtlue 8tg8stion des rwssomes naluretles

d'intkgi-er la production de cette couvertme dans les systhes de production pour l'amdlioratim de la fertilitt5, la lutte contre l't5rosion et les utilisations domestiques dlffdrents services (wlgarisation et recherche) tentent la mise en place dans les parcelles des productem de p h t e s de couvemes B base d'A~&opogongayam. A cot6 de l'utilisation des essences locales dans l'am6lioration de la feItilit6 des sols certaines espkces htroduites sont en phase d'&e adoptdes par les producteurs pour des utilisations agticoles et pastorales. Le Mw.mm cochinc:hinensis et le Sty~osanthesont dt6 exp6rbentds avec les productem de pluskurs villages dans la p d e Ouest du Burkina Faso pour laalimentationdes animaux. Des tests d'adaptation du Munmn dans certaines zones de I'Ouest du Burkina, de m b e que l'amdnagement de soles f o m g h e s pow laalimentation des animaux (bovins p~cipalement)ont &d eEectuks par I'MERA soutenu financi8rement par Sasakawa Global 2000 en 1997. Trois sites ont 6t6 choisis en milieu paysan: Bama, N'DoroIa, et Yasso. L'objectif principal de ces tests &it d'identifier, sur la base des amntes des productcurs, des especes fou~fag8resbien appetdes, productives, rksistantes aux maladies et faciles eatretenir. Mucurza cochinchinensis a dtts 'cornpard au dolique (Lablab purpuretfs) servant de ttSmoin (Sidibd et al. 1998). Les productem, particutikrernent ceux de Bama ont apprkcit! positivemefit la culture et les rendemen&en foh du Mucuna qu'ils estirnent supkrieurs & ceux du dolique, avec m e app6tb'ilitd dquivalente et m e plus gande rksistance a u ~ p e a s (To6 et Segda 2998). Le stockage des fanes a dtd eRectu6 dans des fenils amhagds avec laaidede I'INERA. Ces agro dleveurs ddplorent ntanmoins le fait que la production de semences ait dtd thible, nais ils sons przts B poursuiwe les tests (Sidibb a al. 1998). Les r6sultats de recherche en station et en milieu rkel indiquent que I'exploitation d'une jach8re amdlior6e de ldgumineuses peut Ctre accornpagnde de plusieuts avantages pami lesquels (i) la restauration de la fertilite des sols: les feuilles qui tombent constituent m e matiere comparable tt la fumure organique pernettant plus tard de diminuer b rythme du ddEchement par une culture plus permanente des parcelles existantes (Segda et al. 1997, 1998 a et b, 1999); (ti) la production de fourrage bien appdt6 (Mucrmna cockinchinensis)par ies animaux est jug6e abondante, ce qui pemet de limiter la divagationdes anhaux (Sidibd et al. 2998) et d'amtliorer la production de la fumure organique; (iii) la lutte contre I'drosion {diminution) et le dentissement de l'appauvrissement chimique du sol.

Raisons du succh ou de la non-adoption I1 parait encore tr&st6t pour faire un bilan et &valuerles chances de succ8s des plantes de couverture au Burkina Faso. Beaucoup de travaux sont encore au stade experimental ou de tests chez quelques producteurs. On note cependant m e

motivation chez les producteurs pour l'utillation des plantes de couverture pour amhliorer les soh cdtivds, enrichir ies jacheres ou pour I'alimentation des animaux. I1 existe aussi des dlBrences au niveau de l'adoption. Les pmducteurs semblent prefkrer les gramindes qui se resstment toutes seules d'une campagne a une autre. Ils dvitent ainsi la p6nible opiration de collecte des semences. Ib se contentent de gdrer uniquement cette biomasse par la fauche ou en I'utilisant cornme aire de pgturage pour les animaux. I1 faut noter cependant que tres peu de travaux ont dtt3effectllds en milieu paysan par la recherche agricole. Seuls quelques novateurs l'ont adope dans la zone Ouest, avec pour objectif principal la production de fourrage et accessoirement pour l'amelioration de la fertilitd des sob. Piusieurs contraintes Treinent I'expansion de ces culttrres de c o u v e m , m a l e les dsultats promettern. Les principales contraintes Bvoqudes par les paysans sont (i) l'insertion difficile dans le calendrier agricole des cultures de couverture ou soles fomagbres; (ii) la divagation des anirnaux (Sidibe et al. 1998) et la protection m t r e les feux de (To6 et Kanwd 1998). Le problkme d'alimentation animale en saison skhe 6tant rune des raisons principales de la divagation, la sole fomgkre pourrait watribuer a crder les conditions qui hciliteront son adoption. D'autres contrainks telies que la prksence de serpents dans ceitains mulchs et les difficult& d'approvisionnement en semences de borne qualie (Sidib8 et al. 1998) dans la rkgloa de Samandeni au B u r h a Faso ont dtd signaldes. Le coiit et la disponibilitk des semences semblent Gtre m e forte contraink pour les producteurs et limite I'adoption des plantes de couverture. I1 s'agit essentielkment des semences des I~~pnineuses c o m e la dolique ou le Mucuna. La demande existe mais la production de semence n'est pas organis6e. Les producteurs intdressb n'ont pas souvent la sernpnce pour acheter. Tous Ies productews htkressCs n'ont pas souvent les ressources fmancieres pout acheter la semence. A.titre d'exemple la dolique est m e plante tr&sdemand6e mais dont la semence coiite 600 FCFUg.

Pmg& riialis9 dans la disponibilit4 des semences De nombrewc efforts sont iournis par les structures de vulgarisation et la recherche pour la mise a la disposition des paysans de semences de qualltd. ll s'aglt notamment de lVONGSG 2000 qui foment Ies producteurs en technique de production des semences. Cette structure travaille depuis 1996 au Burkina avec Ies producteurs de la zone. Elle met A la disposition de ces derniers des semences de Mwuna pow I'amdioration des jachkres de comes durdes. L'INERA est igalement fortement engage dans la promotion des plantes de pIantes de couvertures A bavers son programme GRNSP Ouest et Centre. Les semences sont fournies aux producteurs pour la multiplication et pour les tests. Quatre espkces de Id,gmineuses ont dte multiplides pour les productem. I1 s'agissait de M u m a cochinchifiensis,Cajunrrs C@QH, CtmmaIi~ ensformis, et Cahpogoni2(mmmnoides.

Certains p u p m e n t s de producteurs comme les Cleveurs de Beguedo d m le CentreEst du Burkma sont spdcialisds dans la production de semences de l6$umineuses, en parkiculier le DoIipe et le Siratro (Macroptilitm iThop#?'p~~~.eum). La station de recherche de Kou& dispose des semences suivantes qu'elle peut meme la disposition des demand:Mactlna cockinchinensis, Mumnapm~iens, Conavali~ensifomis, Cajonzrs cafan, ai6btS rl double usage (founager), Cdopogonttrm mltcumides, CrofaEariajttncea, et P3gna radiara.Des infrastructures exisent dans cette station pour produire 2t la demande certaines semences, en piuvial comme en irrigud (saison seche). Une petite quantitd de semetlces de plantes de couveme smt produites par la Sation de Farako-ba. Les semences sont foumies l'aan6e suivante aux producteurs qui les utilisent pour lYam6lbrationde leur parcelle ou l'alimentation des animaux. 11 n'existe pas au Burkina de service chm6 de l'inspection des semences produites ilocalernent. Seules les semences provenance de l'exs4rieur font I'objet d'une vMcatioa phytosanitzdre avant la mise la disposition des producteurs. La mise A la disposition des productem chaque am& de semences ne pemet pas m e reproductibilit6 de l'utilisation des plantes de plantes de couveme. car les productem semblent se plake dans un attentisme prolong&. Lorsqu'un productem resent la necessits5 de se procurer de la semence, il s'adresse au prdalable rl la s m m r e qui lui a octroy6 au dkpart. A par& de cette exp6ritnce il serait plus judicieux d'impliquer les productem d2s bs ddbuts des exptkbentations aux techniques de production et de consmation des semences. k u r s contn'butions financi&esou physiques sont indispensables pour assurer le d6veloppement d'un march6 intdriem. De nos jom au B m k h surtout dans sa pastie Ouest 03 la culture attelCe est assez d4veloppee, les productem s'accordent sur le principe de complbmentation de l'alimenhtion. des animaux de trait en saison skhe. Les sous produits ago-industriels sont chhres et hwouvables seubs les soles dbluxagllres sont mesure de rdsoudre la question.

EmIua#on sle /'impact des plantes de couverture dans un syst6me rotatif

maWcooton Ce travail est rMis6 par Traor-4et al. (meme ouwage) & la station de recherche agricok

de FadS-ba dans la partie Ouest du Burkiia Faso.

de c o m ~ m Dans la zone Est oh domine la cultme de s o d o dans IYbcosyst&me pluvial, bs eBets rtSsiduels des l6gmineuses de cmveme associant le Burkina phosphate sur le rendemat du sorgho en rotation sont entrain #&re ddtennin8s. En 1998, les

CR'Wagede plan-

Countryand neiwurk repo&Mappoiis naonaux et du rkeau265

traitements principaux etaient comgosds de jach2re naturelle, de jachkres annuelles amdliordes de Sfylosanthes pionensis, de Mucuna cochjnchinemis, de M u m a pruuiens, de Labhbpurpureus, de Mucuna spp. Kpalwala, de Cajanus cajan, de niBbe fourrager (JAR 71'180-45-11, de jachkre de C~otaiariacmicea + Tephrosia can&&, d'dvrdropogn gayonus, et une culture continue de sorgho. Les traitemenis secondaires ont trait B I'application ou non de phosphate nature1 du Burkina (0 kgha de BP et 400 kglha de BP). En 2999, les parcelles secondaires ont Cte subdivisdes (0 kglha de N et 60 kglha de N) pour rnieux faire ressortir i'eflet des legurnheuses dans la nutrition azotke du sorgbo. Les diflkrents rdsidus des legumineuses ont tte laissees sur place dans le champ. Le suivi de 1'evolution des rksidus a Ctt eflectud chaque mois & inZervalle regulier (IS de cfiaque mois) a partir du mois de novembre 1998jusqu'en mai 1999. Ces difFerentes plantes de couverture ont et6 enfouies en debut de saison pluvieuse 1999. Leur arri6re effet sera rSvaluC sur le sogho, en cornparaison aux pratiques paysannes (sorgho continu aprks la jachkre naturelle). Les rdsultats dkfuritifs seront obtenus la fin de la campagne humide 2999. Un criblage varietal est Bgalement en cows dans la zone Est, depuis la campagne humide 1998. Quarante-cinq (45) espkes de Idgumineuses de couverture sont en criblage dans le but d'dvaluer leurs performances dans les conditions agro pedoclirnatiques de la Station de Kouare. Les observationsprtliminaires montrent que plusieurs especes sont plus productives en ce qui concerne la biomasse aerieme totale 15 semaines apr2s le semis (SAS). Ce sont particulierement Cqjanziscajan (4.6 t/ha), CrotaIa~iacaricea (3.6 tlha), Labiabpurpuueus (3.3 tiha), Mucuna spp. Kpalwala (3.6 fia), Mucuna pruriens (2.6 tlha), Mucuna cochinchinensis (2.2 tha). Dans I1Ccosystkmebas-fond, la selection de ldgumineuses adaptdes aux conditions agropddoclimatiquesde ces zones est en cours, en milieu paysan. Le crblage se &it en contre-saison, en utilisant exclusivement I'hurnidite rdsiduelle. L'eEet rdsiduel des Ikgurnineuses les plus perfomantes sur la fertilitd des sols et le rendement du riz suivant sera apprdcie. Dans le bas-fonds irrigue d'ltengue situ6 en avaI d'm barrage alimentant la ville de Koupela en eau, des problemes lies B la disponibilite de l'eau pour toutes les parcelles se posent en saison skche; plusieurs producteurs sont dans I'impossibilitd de pratiquer des cultures maraicheres dans ce bas-fonds (les parcelles les plus Cloigndes du barrage). L'objectif principal de cette etude est de dkterminer Ies facteurs socio-dconorniques qui pomient influericer Isadoption des technologies d'utilisation des jacheres amdlion5es par les productem rizicoles. Un criblage de Iegumineuses de couverhrre est &@lenient en cours en vue d'apprdcier lew comportement au corn de la saison seche apr& la dciIte du riz;cette dvaluation devrait pernettre d'orienter le choix vers m e ou plusieurs Idgumheuses adaptkes utilisables apds le riz c o m e cultures de couverhrre en remplacement de la

jachdre naturelle. L'effet des rotations c u l ~ e ~ c l u a des m tcuMes maraichereset r et sw I'e5volution de la productivitts des sols B de c o w ~ u l'enherbement travers les effets hduits d'une culme sur l'autse sera appdcit5. Quatre productem ont choisis pour la conduite des tests avec comme I@mheuses de c o u v en ~ contre saison Mtccuna cochInckinemis,M~unmapmriemvan stilis,C @ mc@m,et Crotalariajmcea. Au c o w de la saison hmide 2999, des c ~ s d ' o b s m a t i o nont Btd hplantt5s dans les parce21es d'essai (dans celles ayant tstd O G C U ~ ~par ~ S les l5gumineuses et dans lesjachhs naturelles servant de thoin]. Un suivi des di&ents parm&es du rendement est en cours, ce qui permem de statuer sm lYeEktdes cultures de contre saison (ldgmineuses) sur le mdemmt du riz en rotation. Aussi, dans le cadre de CoverCropNet, I'DIEUA & initid m e activite5 de criblage pour b zone semi-aride du centre du.pays (Zaugmore, cet ouvrage). Huit especes de ltsgumineusesont f i t I'objet de test de comportemmt dans la zone centre du Burkina Faso (Saris, 800 mnr de pluie par an) en m e de dlectionner ce11.e~qui pourraient gtre intdgrtes dans un systhe de culture en association avec des ct5rdales.

Conclusion L'&vtSnementdes couvertures m4liordes est A ses ddbm au Burkina Faso cependant on note un engouement serieux des producteurs pour cette pratique. Les services de ddveloppement (senice d'agriculme], ies O W (SG 2000, Assistance agoBcologique) et de recherthe (INERA,IRD,CIRAD-IEMVT) sont fortement impliqu6s dans la mise B la dispositiondes productem de semences approprides et de techniques de gestion de ces couverhms. I1 reste cependant la mise en commun de l'ensemble de ces exp8riences pour constituer au niveau du pays un pool de travail m les plantes de couvmhire. De plus en plus ces relations sont entrain de se d e r @avers l'organisation de discussion. Plusieurs ames expkriences sont en c o m d'ext5cutian dans ie pays et la %f de la prbente campagne serait le moment indiquB pour fake le point de la situation.

Segda Z., V. Hien, E Lompo, J. Bayala, et M.Becker. 1997. Gestion amkliodede laj a c b k par I'utilisation de lâ&#x201A;Źgumineusesde couverture. Pages 233-139 drms La jach&re, lieu de production, C. Fbret @if.).CORAFnRD ex ORSTOMNE, Dakar. Segda, Z., V. Him, F. Lompo, et M. Eecker. 1998a Gestion amClioree de lajachgre par utilisatioa de lkgumineusesde muverture. Pages 189-199 dans Plmtes de cowerture en B q u e de I'Ouest: une contributionB 17@culmedurable, D. Buckles, A. Eteka, 0.Osiname, M. Galiba, et G. Galiano (eds), Centre de Recherche pour ie D6veloppement International, Bibliothkque Nationale du Canada. Segda Z., V. Hien, et M. Becker. 1998b. Conttibution de Mucum cmhinchinensis dans le mntrate des adventices et dans I'amtlioration des rendements de riz plwial. Communication

pksentde i la 8' confdrence de ['Association M c a i n e de la Fixation Biologique de I ' h t e (AAFBA), 23-27 novembre 1998, CapeTown, Afi-ique du Sud (B p d t r e ) . Segda Z. et h.I.3. Toe. 1998. L'amtlioration de la fertiliM du sol par les ltgumineuses de couverture.Pages 125-131 dnns Actes de ]'Atelier e i o n a l cccultures fourragbres et DCveloppement durable en zone sub-humiden, Korhogo (Gate d'ivoire), 26-29 mai 1997. CIRDES (Burkina Faso)flDESSA (CBte d'Ivoire)/CIW, Montpellier, France.

Segda Z., V. Hien, et M. Beckcr. 1999. MYCUM cochifiChiwnsis dare les s y s t h e s d'associations et de rotations culturales: cas de la zone wtonnikre du Burkina Faso. Communication pdsentke au stminaire international: ((La jachkTi: en Afrique Tropicafen, 13-16 aMil 1999, Dakar,Sâ&#x201A;Źnâ&#x201A;Źgal { I pdtre). Sidibe A.G., M.3. Toe, et 2. Segda 1998. Contribution du MUCUMet du dulique dans I'amtlioration de la production laitikre bovine. I. Productlvitb du MXCUM et du doiique en milieu paysan (cas de Bma, Kayao, et Yasso). Rapport d'activibis 1997. INERNSG 2000, D6partement Prodmtions animales, Bobo Dioulasso. 7pp.

M.B.et A.B. Kanwe. 1998. Contribution B I'amtlioration du dispnible forrager en m e subhwnide :syntfibe des tavaux de la recherche agronomique ay B w h Faso. Pages 117-124 dans Actes de I'Atelier &ional ctCultures f o w b ~ e et s DCveloppernent durable en zone subhumiden, Korhogo {Cdk d'Ivoire), 2 6 2 9 mai 1997. ClRDES ( B u r h a FasoyIDESSA (Ctite d'Ivoirej/CIRAD, Montpellier, France. Toe,

Country report on cover c r ~ p s activities in Ghana R Osei-B~mu Cmps Resemch Instirufe, Kumusi. Ghana

0 0

o 0 oa

Ghana

Abstract The year and mode of introduction of cover crop Zegmes into Ghana is uncertain. Since 1992, researchers, extension agents, &.men, and other stakeholdas h the agricultural sector have been actively working on improved fbllow systemsflegume cover crops as a soldon to weed and soil fertility problems. The major cropping system is therainfed mabMumcc intemopping/roationsystem. Anorher important system is dry-season vegetabb produ&*an. Each year an estimated 300 thmers t a r h e various coyer crop systems in vanvanous projects. Seed is produced by those fkmers and also 500 kg of Mnma swd is produced and sold by $he Atebubu eqmimental.farms amuaily. There are seyerd oqpaizatiom mvoIved in wark on coyer crop systems. Therefom the Ghana Cover Crop N W o k (GCCN) was established in 1999 to facilitate flow diaformation about woxk on coyer crops in Ghana

Rhm& L'am4e et le mode d'introduction des ptantes de m v e r m e de Z 6 p h m e s daas Ghana d m e m t incertains. Depuis 1991, ts chercheufs, les agents de vulgarisation, les agricuZtemet k s autres parties prenantes tramilient activementslrr bs sys#mes de

CountryandnelwoTk repo#Rappons ~tiomuv st du r&seau 269

jachkres am8liories/plantes de couverture de ltgumineuses wmme solution aux problkmes d'adventices et de fertilite du sol. Le systkme de production prbdominantassociation/rohtion m a r s - M u c u n ~ s tpluvial. La production maraichere en saisosn skche est un autre systeme important. Chaque annee, environ 300 agriculteurs testent les diffkrents systkmes de plantes de couverture dans le cadre de diffbrentsprojets. Ces agriculteurs produisent 6galement des semences et la ferme expCrimentate d'Atebubu a Cgalement produit et vend chaque annee 500 kg de semences de Mucuna. Plusieurs organisationspaiticipent aux activies relatives aux systemes de piantes de couverture. Par consequent, le Reseau sur les piantes de couverture du Ghana (GCCN) a etC mis en place en 1999 afin de faciliter la diffusion des informations sur les activitbs relatives A ces plantes au Ghana.

Inhducfion Many farmers in Ghana are confronted with serious problems of weeds and soil degradation. The traditional bush fallow system is practiced in many areas as a solution to these problems. However, pressure on land has forced farmers to reduce fallow periods to the extent that they are no longer effective in improving the soils. Since 1991, researchers, extension agents, fanners, and other stakeholders in the agricultural sector have been actively working on improved fallow systems/legurne cover crops as a solution to weed and soil fertility problems. Legumes such as Centrosema and Pueraria grow in the wild in many parts of the country. Others, particularly lima beans {Phmeolus vuigauis), Mucuna, and Canavaiin have been grown as lraditibnal food crops for several centuries (Osei-Bonsu et al. 1996). Seed (dry or fresh in the pods) of tl?ese legumes are even sold in markets in some villages and t o m s for food.

Pad work on legume cover crops The year and made of introduction of these legumes into the country is uncertain. Some fanners however indicate that the Europeans introduced the legumes as an intercrop in plantation crops (personal communication with fatmers). There has also been research work on legume cover crops in the past, particularly in the universities. However, activities in this area had virtually, if not totally, halted before 1990. The main catalyst of renewed interest was scientists' involvement in work of the Collaborative Group on Maize-based Systems Research. Though this project, scientists, extension agents, and frymers in the country interacted and shared experiences and information (COMBS 1992) with cover crop experts and farmers in other countries in the subregion, especially in the Republic of Benin and Cameroon.

210 Oovernops for n-I

r e s o w rnanagemenrmtantesde muv81Wr8 eigastlon des ressaurces naWe!Ies

Institutionsinvohred in wver crop activitiesl in 1991, work on cover crops was limited mainly to Maccuna (Mumapruriens vat-" 1cfiCis).The Crops Research Institute in collaboration with the Ministry of Food and Agriculture were the main institutions involved in the work, which was conducted onstation and on-farm. Following progress made in this work, many organizations became interested in the technology and currently more than ten organizations and institutions are implementing cover crop programs. These include: Land and Water Management Project of the Ministry of Food and Agriculture sponsored by DANZDA. The project has for the past 3 years offered training on cover crops as part of the Land and Water Management course that is organized each year to extension agents. it also conducts o n - f m research on Mucuna cover crop technology. The Sedentary Farming System project in the Brong Ahafo Region sponsored by GTZ is also involved in on-farm research on cover crops mainly Mucuna, pigon pea, and Cmavalin. The main systems being tested are maize-Muma relay/ rotation systems and Canavalfa+assava intercropping systems. The Integrated Food Crop Systems Project (IFCSP) of the Ministry of Food and Agriculture and the Natural Resources Institute, UK. The project is looking at ways to improve soil and water management for vegetable production and is working with farmers to evaluate different green manure for their e e c t on vegetable growth. Mtrcuna and Canavaiia are studied for dry-season vegetable production. The Kumasi Natural Resources Management Project managed by the Natural Resources Wtute,UK im collaboration with the University of Science and Technology. The project is working o n - f m in the periurban areas to improve soil fertility and the yield of dry-season vegetables through mulch farming. Sources sf mulch being studied are Mucma and grass. * The Crops Research Institute>the Soil Research Institute, the universities, and ihe Savanna AgFicultura1 Research Institute also carry out cover crop research activities. Cover crops being tested include Mucana, Canavczlia, Cafopogonim, Stylosanthes, Centrosema, and Puermia. Other projects involved are the Ghana Organic Agricultural Network (GOAN) and World Vision International.

Promising cover crop systems Maize-Mucuna intercroppingfrotation system The most promising covet crop technoloy that has been developed is the maizeM m a intercropping system followedby mabe as a rotation crop. Thf:system is used

for the control of noxious weeds ancUor improvement of soil fertility. In this system, Mwmna is relay intemroppedwith make in the major season and lefi as a Hlow in the minor season. This is followed again by maize, which is planted, directly into the accumulated mulch in the following major season (Fig. I). Two varieties of Mt(c11na (Mumapruriem var. ufiIisr)are wed: one with a Mack seed coat and the other with an ash color. h y farmers 'however prefer the black-seeded M t c m a because it matures late and is more effective in weed control.

Green rnakeldry-seasanvegetable production Dry-season vegetable farming is a major s o w of income for fanners tiving in tbe periurban areas in Ghma The vegetables are normally gown in valley bottoms in rotation as shorn ia Figure 2. The major constmhts limiting yield during this period are low soil fertility and stress resulting i?om heat and inadequate soil moisture. Currently, an alternative

J F M A M J J A S O N D J F M A M J J A S O N D Pigue 1. Calendar of maize-Mucuna relay intercropping (southern Ghana).

1 1 1 1 1 1 1 1 1 1 1 1 1 -1 ~a~uralfa!tow//

1 1 1 1 1 1 1 1 1 1 1

Vegaw i

Mwna

-V

1 1

Fig2 Cropping calendar for periurban vegetable produdon in inland valleys in Ghana showing e mtation of green maize ioUowed by natural fallow or Mucuna and dtpeasan vegetables.

272 CoVprcmpsfornaturalresourn managemeW1ante.sde cowerture etgestlon des ressomes na mreles

system of rotation (system 3) has been developed and is being tested by farmers. 'Ilzis system involves planting the vegetables on the flat or on n'dgs with M1ccuna mulch. Vegetable yields have been significantly increased through moisture conservation and reduced taperame.

Progress in seed supply In Ghana, kmers who grow Mzccma for weed control or soil fertiliq improvement are the main suppliers of seed to interested fanners and organizations. ApaFt from these some 500 kg of Mtmma seed is produced and sold by the Atebuh experimental f m s mually. The station grows Mucuna as a cover crop for maize production and sells the excess seed to interested organizations. Seed is nomdly stored in sacks after threshing and is sold at the farmgate. The major problem associated with seed production is burning by bush fires before harvesting. Apart f b m Mtlczm~seed,the Ministry of Food and Agriculture had been involved in the production and sale of limited quantitiesof seed of Stydosanihes to livestock farmers. farmers,

Examples of cover crop training materials Enhanchg research on Mucxna as cover crop (Osei-Bonsu and Asibuo 1995) Cover crops in sustainable cropping systems (Osei-Bonsu and Ennin-Kwabiah 1993) Grow more maize with Mucuna cover crop (Osei-Bonsu 1998) Traditional food uses of Mucunapruriens and Canmatia ensgormis in Ghana (Osei Bonsu et 1 . 1995.

Adoption No formal studies have been conducted to determine the rate of adoption of cover crop systems in the country. Each year an estimated 300 farmers test the various cover crop systems. The rate of adoption is low due to two main reasons. F i there is no specific project for promotion of the technology in the country. The next problem is the numerous bush fires that destroy the dry cover crop mulch. Burning reduces the benefits that could be derived from the cover crop and discoutages adoption. Seed availability bas also played a major role in extending the technology. Many farmers who plant cover crops lose their seed through burning so they are unable to replant the following season.

National nehnrork on cover cmps On 29 August 2999, a one-day nmional workshop on cover crops was held at.the Crops

Research Institute conference cater at Kumasi with the following objectives: To bring stakeholdersinvolved or interested in cover crop techno lo^ development and promotion together

To exchange experienceand COOfirture activities on cover crops To f a c i infarmdon ~ ~ flow and seed a v W d i t y To develop a strategy to enhance adoption ofthe technology. The workshop was organized aad cosponsored by the b p s Research Institute and the Sedentary Farming Systems h j e c t (SFSP) of GTZ. During the workshop two technical papers were presented on the topics: Current status of cover crop research at the Crops Research Institute &Ghana Experience an cover crops within SFSR At the end of the workshop, a national network on cover mops cded the Ghana Cover Crop Network ( G C W was fomed with the following executive members. Chirperson: Dr C. Yamoah, Soil Research Institute, Kumasi Secrefmy:

E-mail: cha.yam@ugtcc.a~caodine.com.~ Mr F! Osei-Bonsu, Crops Research Institute, Kumasi

E-mail: poboosu@ghaaa.com Mr J. Anthofer, DED-SFSP,Stmymi Email: gtzsm@ncs.com.gh Mr Loos, GTZ-SFSP, Smyani Dr B.Asumady Oops Research lristihte, Kumasi, Ghana The aim of the network is to facilitate work and promotion on cover crops and members will ineet between January and February each year to share experiences and information and plan activities for that year. It was recognized that international and regional netwoh such as CEPCA could play a vital mle with regardsto i n f o d o n Assistants:

needs of GCCN.

References CollaborativeGroup on Maize-based SystemsResearch (COMBS).1991. Soil F d q improvement and weed suppression stIuough legume-based technologies (An appmach to techno1ogy targeting). CollaborativeResearch Paper No. 1. IITA, Ibadan, Nigeria Osei-Bonsu, P., D. Buckles, F.R Soza and J.Y. Asibw. 1996. EdibIe cover crops. ZLEIANewsletter for Ecologically Sound Agriculture 12(2): 30-31. Osei-Bonsu, P. and J.Y. Asibuo. 1995. Enhancing research on Mwxria as wver m p . Pages7782 in Organic and sedentary agriculture, edited by V. Akita, P. Schroder, and S.K. Bemile. Proceedings of Seminar on Organic and Sedentary Agricultwe, 1-3 November 1995, Science and Technology Policy Research Institute, Accra, Ghana Ministry of Food and Agriculture and Deutsche Gesellschaft Fur Technische Zusammenarbeit (GTZ), Accm, Ghana Osei-Bonsu, P.and S. Ennin-Kwabiah, 1993. Cover crops in sustainable cropping systems. CRi Crop Management Research Tsaining Guide No. 37. CRI, Ghana

274 CBvmmp k?rnafural msomn manapmmVPlantssde cauv~rfurt)Bf QeStion des wssou~es natureIIes

Osei-Bonsu, P. 1998. Grow more maize with Murum cover crop. Training manual for the Land and water management training course, April 1997 and Mmh 1998, Soil Research In&tute Conference Center, Kumasi, Ghana Chgmized by MOFA and DANTDA. 7pp.

Osei-Bonrm,P.,D. Buckles ER Soza, and I.Y. Asibuo. 1995. Traditional food uses of M z w m Mexico, D.E:CZMMYT.

pnvienr and Cammalia enrtfomis in Ghana. CZMMYT internal Document.

Les plantes de couverture au Togo :

un bref resumi?d'activites LK.Fanidrede Inr~irurdeConseiIet dlAppui Techniq~h . 6 , Togo

La promotion des ldgumineuses a eid notablement rCalis& autour du Leucaenu, du C+w ccajan, k soja, et du Mucunu. L'introduction du Mucuna au Togo a Ctd effective avec I'avenement de Sasakawa Global 2000 des 1994. 11y a eu une diffusion des semences au niveau des paysans de la +*ion marltime surtout Mucwa spp. Rajada et M. cochinchinensis. L'engouement manifeste des producteurs du sud-est du Togo iait que des paysans convaincus des effets du M u c m et qui ont les moyens n'hesitent pas 8 en acheter auprks de leurs homologues producteurs oh les prix varient entre 250 et 400 FCFA le kilogramme. Beaucoup d'organisations de vulgarisation et de promotion des technologiessimples et durables s7int6ressentaux plantes de couverture suttout pour le relevement de la fertilitd des sols ddpdes. Une br&vedescription de ces acteurs monlre la possibilit4 d'etablir un riseau national.

Leucaena, Cajanvs cujan, soybean, and Mucum were used for the promotion of legumes. The introduction of Mucum in Togo was effective through Sasakawa Global 2000 in 1994. Mainly seeds of Mucunu spp. Rajada and M. cochinchinensis were distributedto farmers in the maritime region. In the southeast of Togo, farmers were so endmiastic about Mucuna that those who were convinced about the effect of the crop and could afford it did not hesitate to buy seeds from other farmers at a price of FCFA 25W00kg. Many extension agencies and simple and sustainable technology promotion organizations are interested in cover crops especially for their potential in terms of soil fertility restoration in degraded lands. A brief description of the stakeholders highlights the possibility of networking at national level.

P&en&tion des manisations s'int6ressan.t. am plants de couverture Des organisations de vulgarisation et de promotion des technologies simples et durables a k i quc: des ONG (organisations non gouvemementales) s7int4ressentaux plantes de C O ~ surtout Y ~pour ce qui c o n m e le rel&vementde la fertilite!des sols d6grades. On c']tern mtres autres: Le PUDY (Projet &Organisation et de Developperneat Villageois) B travers sa division de promotion et d'appui Vagroforesterie et gestion de la fedlite des sols. Le P O W couwe 6 p r 4 f e m s toutes daas la dgion maritime au sud du Togo. ONG-FID (Femme Initiatives D6veloppement) intenrient dans la zone pbriurbaine au nord de Land et dans bs villages situds dans au sad-est de la zone la m e d'qloitation des phosphates de Hahotoe. ACVR (Association des Communae Viageoises Responsabks) dont la zone d'intmention couvre les pn5fectms de Yoto et de Vo. Sasakawa Global 2000 ayant appuyb le service national de vulgarisation agiwb. LX ' CAT mstitut de Conseil et d'Appui Technique) cow~antI'ensemble du itmitoire Togolais et charg6 de la promotion dss technologies simples et 6prou~des. XTRA (indtut Togolais de Recherche Agronomique) par le biais de la recherche theSmatique dans le cadre des systemes de cultures. EDC-A (Inmational F d W r Development Center-Africa) ssur les essais d'utilisation du phosphate nature1 togolais et du mucuna pour le relhernent de la fertilitt5 des sols daas la d g o n maritime. CFAE-SOS(Centre de Formation Ago-bconornique) dans la rdgion de la Kara au nord Togo. AVOTODE (Association des Volontaires Togolais pour le Dbveloppement) dans la prdfecture des Lacs au sud du Togo. L'Eglise Baptiste de M o r W dans la rdgion des plateaux au nord-est d'Atakpme! GARED (Groupe &Action et de Reflexion sur 1"Enviromement et le Ddveloppement) bas6 A Lome.

Progds d'adoption des systernes de culture de phntes de couverture La promotion des plantes de couverhwe a dte notablement tdaliske autour du Lelccaena, du Cojanus cajan, b soja, et du M t m n a Larcaena et Cw4unuscajan ont kt6 utilisds dans les systkaes de culture en couloirs dans le sud et le nord Togo dans le cadre des programmes d'agroforesteiie r4alis8s par les paysms avec l'appui des ONG

Countiyandnetwork repwWRapp0rtsriationam et du r h e a 277

(Care International, GTZ,Peace Corps, etc.) et des services publics.de vulgarisation agricole. Le soja a ktd developpd dans le nord Togo avec l'appui de GTZ pour l'am6lioration de !a fertilitd des sols d'une part et I'alimentation humaine d'autre part. Cintroduction du Mucuna au Togo a dtb effective avec I'avhnement de Sasakawa Global 2000 d&s 1994 i partu des parceIles test de production sewant d'unitds de d6monstration et de conviction des paysans sw l'amdlioration du rendernent de Ia parcelle et la lutte contre les mauvaises herbes telles que le striga et l'lmpercita cyIin&ic~(chiendent). Pr4.s de 1000 paysans ont dalise ces patcelles test. Ces I6gumineuses aussi Wen avec d'autres telles que CrotaImr'a spp., Aeschynom&e hispix, Stylosanthes, et Dolichos iabIab sont iomrnent appibks par les animam et developphs au niveau des piturages des ranches et centre de recherche zootechnique (Av6ionou, Addld, Namiild). Avec la iEn des projets ayant wlgarisd ces Mguminmes, le suivi de ces paysans s'impose pour apprdcier leur niveau d'appropriation et legr &&raiion continue dans les syst&mesde cuIture. N6anmoins il y a eu m e d3hion des wmences au niveau des paysans de la dgion maritime surtout pour M u m a spp. hjada et M.c o c ~ i ~ h i ~ i s pour la zone d'encadrernent de PODV et FD.Des Sbiestaux de levee dus it une perk de pouvoir geminatif des semences sont souvent signal& par les pays-. Selon ces deders les conditionsde "stockage, d'emballage (plastiqiie) et parfois la qualie de la parcelle" peuvent en &re la cause. Des jaunissernenis des feuilles sont dglement constatds (Zone PODV). Dans la &$on m a r l h e (sud-est du Togo), la diffusion du Mvcvna se trouve Sirnit& par des disponibilitr5s foncieres t& rdduites qui affectent au nlveau de ceadzns pmduciews la pomuite de ette techaologk. On sigaalera e m autres que dans le cadru: de la promotion des plantes de couverture et la valorkd0~1du phosphate nature! togolais, le PODV et I'ITRA en colIaboration avec I'IFDC-A ont initid des actions de vulgarisation de ceiie techologie. Des contacts avec ces diEhntes institutions sont n6cessdws pour app&ier le niveau d'adoption et de diffusion de cetk tecbnologie en rapport avec I"e~1vhmement du paysaa. Notons que la baisse de la iertditk des sols et les moyens d'y remMer constituent cemhes des prt5occupations exprimks par les productem au cours des diagnostics p a r t i c i p e &alisds par I'ICAT dans le cadre de I'identification des besoins d'appuicomeils. Ceux qui ont 6. d6jB en contact avec des plantes de couverture notamment le ont ernoigne des effets de cette Idguminewe srussi bien dans le relevement de la f e a t k - des sols que dans la Iu#e con& les mauvaises herbes mais n'ont pas le m&riel vBgdtal et des informations n6cessakessurtout sur la consommation humaine de cette Idgumheuse pour me r6elle appropriation. Dans le cadre de h mission de I'ICAT, la promotion des plantes de couverture et des en@ verb sont des opporhmitks de mises a la &position des producteurs des

278 Covarc~ops fwnahrm! resouras managemenVPlantesde cauvemfe 13 gestian des resumes nalurelles

technologies simples, CprouvCes et adaptdes B l'environnement a m e l des syst&mesde production pour I'amClioration de la fertilite des sols, la lutte conhe les mauvaises herbes, la gestion de la jackre et I'alimentation du bktail. Ainsi I'ZCAT reprksente sur

toute Mendue du temtoire national constitue un canal de promotion des plantes de couverture.

Progrb r4alish dans la disponibilitb des semenDans le cadre des appuis pour la promotion des plantes de couverture par les ONG et ies services publics de vulgarisation, les semences ktaiem foumies gramitement aux eandidats mtte Lchnologie et les productions rachetees et distributes aux autres productern pour pennettre sa diffusion. Pour le Muelma, SG 2000 a prockdC ainsi A @avers Z'installation et la multiplication des parcelles tests. Les effets convainquants du Mzrnma surtout sur ie rekvement de la fertilitd des sols et le conhcile du chiendent amhent parFois des paysans du sud-est du Togo dvolumt sur des sols de terre de barre d6grades et kpuisds A s'en approvisionner aux prix variant de 250 B 400 FCFA le kilo aupr&sde leurs homologues producteurs. En I998 il a 6td rkceptionnk du Cootdonnateur du ClEPCA cent trente six (136) kilogamines de semences des plantes de couverhue dont: ZOO kg de Muczma spp. Rajada 20 kg de M z m a spp. Beta 5 kg de CmtoImia oc~obeuca' 1 kg de Aesthynomene hispix ZO kg de Mamaprtrriens var. =tiffs. Toutes les semences ont Btd mises la disposition des institutions telles que PODV, OM-FID (&mine Initiatives Dhetoppement), ACVR (Association des communautt5s Viageoises Responsables) et des paysans prdcddemment encadrCs par Sasakawa Global 2000.

Suid des parcelles des paysans et bmation Ces aphtions dtaient effectivement rdalisees dans le cadre du projet SasakawaGlobal 2000. Mais la fin de ce projet qui a egalement co'incid6 avec le processus de

remwturation des services agicoles au Togo n'a pas permis de poursuiwe ces activitds. Toutefois avec les partenaires (FID,PODV,ACVR, CFAE-SOS et autres), des contacts sont en corn en vue de i'organisation des visites de terrain pour apprecier la situation d'appropriation de ces Lchnologies par les paysans d les difficultds renconees.

Persp&"va La situation de I'utilisation des plantes de csuverhm et des engrais vem est A apjxdcier au niveau d'une part des institutions les vulgarisant et de I'autre des paysans se les appropriant. L'identification des utilisateurs de plates de couvewe est & realiser aux fins d'envisager la mise en place d'un kseau national. ~a-participationA. la production des fiches techniques d'utilisation des plantes de couverture par I'ICAT et A la formation des Twhniciens Spicialist5set productem de semences dans le cadre des actions de promotion et de transfert des technologies sont a poursuivre.

sont lides B m e inggation plus diroite de l'agricultutu: et de I'elevage. On s9a&ndti ce que la &habilitation des rkserves de piiturages actuelles e n w e une utilisation accrue des 16gumineusesfourragd~sdans le nord du Nigeria.

Nigeria is endowed with a good tropical climate and abundant potentially Lrtile land, capable of sustaining the production of food and cash crops to meet the needs ofthe growing population. However, agcicultutaI production is almost entirely in the hands of smallholders employing a low level of technology and productive efficiency. The typical productive unif is a M y farm dabout 1-3 ha Farming operations depend almost entirely on family labor using traditional band took. In Nigeria, as in most parts of tropical Africa, there were traditionally two distinct types of fanning systems: pastoral and atable. The pastoral system relies on wetseason and dry-seasoa grazing lands and people and a n W move back and forth between them. Similarly, the arable system originally relied entirely on shifkg cultivation: the fanner moved on to a new area when the fertility ofthe soil declined and when the weeds on the farmland became unmanageable. However, increasing population pressure has caused some changes in these systems. For example, the length of &Uow period has shortened and around urban areas, land is more or less under continuous cultivation. This often leads to soil nutrient depletion and degradation of the soils for wEch rest periods are deemed necessay (Young and Wright 1980). Furthermore, the rapid expansion of farmlands since the Green Revolution campaigns of the 1960s has encroached on the &aditional grazing Imds ofthe pastoralists. The consequence is the evolution ofa mixed fanning system, whkh is the natural meeting point ofthe two systems. in Nigeria, especially in the subhumid zone (Fig. I), the separation between the pastoral and arable systems is n m w i d g and most systems now include livestock. The relationship is mutually beneficial because crop residues play a major role in the dsy season feeding of livestock whilst animals provide traction and manure. The important role of forage legumes in crop a d animal productio~~ is no longer questioned. Rather, the inclusion of herbaceous forage legumes in the h i n g systems ofTers a unique opportunity for solving the many-faceted problems of smd-scale agriculture in terms of: declining soil fertility invasion of farmlands by noxious weeds lack and poor quality of dry-season forage for livestock.

282 Cover craps fomaluwIresomemanagementPlantes decouvs&r. et gestion des ressources natmfles

The major pressing issues are therefore: How can such interventionsbe made? What level of modification to the present systems is needed? Which are the appropriate legumes to use?

Forage legume production in Nigeria The need for good quality forage plants for improved livestock production created an interest in research in forage production. Forage evaluation therefore has a rdatively long history in Nigeria, especially in northern Nigeria where forage species were fitst introduced in 1935 (Agishi 1983). Between 1956 and 1961, about272 pasture species were evaluated at various centers in the subhurnid zone. At the National Animal Production Research Institute (NAPRI), Shika Farm, 97 legume species were evaiuated between 1956 and 2977. Fifty-four of the species were found to be adapted to the different zones of the Nigerian savanna and 18 species were recommended for largescale production and use [Table 1) (Agishi 1983). Several of these forage ligume species initially meant for pasme improvement also meet requirements as cover crops. Examples are heraria phaseoboides, Cabopogonim mumoidar; Muczrna pnuiens, and Lablab purptrreus.

Seed production and distribution Seed production is of vital importance in agricultural development be it for food crops or pasture crops. Unfortunately, successive Nigerian governments have tended to accord low priority to pasture seed production. There are no incentives for

Nigeria

Figure 1. The subhumid zone of Nigeria.

Country and nefworkrepoWRappr& nationaux et du rBseau 283

-fable 1. Forage legumesrecammendedby W R l for various ecologicalzones. Eoologiwl zone

Species

SQS

NGS

Afachis hypogaea Cajanvs wjan Calopogoniurnmucunoides Centrosemapubescwns Desmodium intorturn Glycine maw GIycins wightii Lablab puwureus Leucaena {euwoeptraia MaciwptiIium aimpurpureum Mucuna pmriens Puelm'a phaseoloides Stylosanthes guyanensis cv. Cook S. guyanensis cv. Endeavour S, guyanensis a.Schofield S. hamata a.Wrano S. humjhs Vigna sienensis Source: Agishi.1983. SGS = southern Guinea savanna; NGS = norlhem Guinea savanna; SS = Sudan SaMtIM

entrepteneurs to go into commercial production of pasture seeds, so forage seed production is mostly limited to government farms and research institutes. Consequently, utilization of both selected and adapted species is usually constrained by lack of seed. In 1977, a seed production promoramwas started in Kachia (in the northern Guinea savanna) by the Federal Livestock Department (FLD) of the Ministry ofA@cultwe and Natural Resources. The objective of the program was to multiply adapted forage species and disttibute the seeds to state governments. Among the legume species included in the program were Siyilosanthes hamata, S. guyanensis, S. hm.zir'is, Centrosema pslbescens, Desmodium intorrum, and Lablab pzrrpurem. The few existing commercial producers do not adhere to proper seed quality standards, and there is a tack appropriate production, curative, and storage hcilities. Moreover, the available tow quality seeds (Table 2) are often marketed at a prohibitive cost. At NAPFU, production of forage seeds commenced over twenty years ago. The Institute remains the major seed producer of most forageicover crops in the country. The eight cover crops which have received most attention are Lab1ab cv. puvpureus (Lablab), M u m a pruriem (Mumnu), Sty!osanthes hamuta cv. Verano (Verano stylo), Centrosema spp. (Cenb-o), Chamaecrista rotundfolia 10918 (Wynn cassia), Macro@iorna unvomm (horsegram), Calopogoniwn aumnoides (calopo), and Pueraria phaseoiloides (hero).

284 Covercrops for nahrml resource managemenWlantes de corn-

etgestion des rsssourcesnaturi?IIes

Table 2. Quality of commercially supplied stylo seeds for fodder bank establishment

Stylo type

Compositionby weight (O/o) Styto Sand Weed

S.hamats EY. Verano

S guyanensis cv, Cook

Germinability

Trash 4 1

r/.) 60 69

Verano stylo was the species initially produced and is still available in NAPW in larger quantities than other species (Table 3). The increased production between 1985 and 1987 was in response to requests from some government agencies. Lablab ranks next in quantity of seeds available (Table 3). As a dual-purpose legume, the production of seed and forage has gained wider acceptance than other cover crops. The two cultivars, Rongai (white and brown seeded) and Highwoflh @lack seeded) are produced but there is preference for the white-seeded cultivarar Mwcuna was the first forage to be used as fodder at NAPRI but seed production has not been significant (Table 3). With increases in demand for use as cover crop by international and national agencies, the production of both the black and white-seeded cultivars is expected to increase. Seed production of C.pubescens dates back to 1976. The quantity of seeds produced varied with time but not more than 100 kg annually. Stakiig was found to improve seed production. Within the last 5 years, there has been a shifi in emphasis to C.pascomm cv. Cavalcade (an annual) which is faster growing and more suitable to the semiarid zone. Wynn cassia gained prominence with the introduction of higher yielding accessions. Its forage value appears low but its use as a cover cropigreen manure is on the increase. Seeds of horsegram, calopo, and puero are produced in small quantities. With them being used more as cover crops, the seed production of these species is being intensified. The major institutions presently involved in seed production and multiplication in Nigeria are: The National Animal Produdon institute (NAPRZ), Shika The institute for Agricultural Research (iAR), Samaru The international Livestock Research Institute (lLRÂŁ), ibadan The International Institute of Tropical Agriculture (IITA), ibadan. Aftes the multiplication stage, the production of more seeds involves the joint efloxts of NAPRI, IAR, nongovernmental organizations (NGOs), government extension services (GBS), and some organized farmer groups.

Table 3. Quantities (kg) of =vet crop seeds produced at W R I , 1493-1998. Species

1993

1994

1995

1991

1997

1998

Labiab

170

811 296 219

570 100 1000

960 200 1290

600 150 1800

300

Muma Verano Slylo Centro Wynn Cassia

150

890 241

Seed storage and distribution Seeds are normally packed in paper bags/envelopes, cloth, or polyethylene bags of various sizes (5-100 kg). The ideal type of storage, in conditioned rooms (where optimum relative humidity and temperature are maintained), is available mainly at lITA in badan, ihe National Centre for Genetic Resources and Biotechnology (NACGTCCLB) in Ilradan, and a few commercial seed enterprisessuch as Premier Seeds and the United Africa Company WAC). At NAPRI, cover crop seeds are stored on wooden pallets in rooms which are subject to changes in environmental conditions, however a conditioned seed store is almost completed through the support of a World Bank assisted project, the National Agricultural Research Project WARP). Wgth respect to seed distribution, seeds obtained fiom the national agricultural research institutes, government extension services, ILRI, and IlTA are multiplied by the recipients (NGOs, educationai centers, farmer groups, and individuals) and distributed in small quantities to other users. Usually no reference to the original sources is made except when seeds are required in large quantities. The distribution of some cover-crop seeds made by NAPRI from 1995 to 1998 is presented in Table 4.

Inspection of fields and stores for disease incidence This activity is part of the mandate of the National Seed Service @SS) but it has not commenced for cover crops. At NAPM, field inspections (on-farm and on-station) are canied out by experienced staff, Diseased plants are rogued during the vegetative and flowering stages. hsecticides are sprayed to control insect pests. At present there is no monitoring of incidence of diseases and pests on stored seeds.

Pmbiems associated with seed produdanof cover crops Among the constraints to the development of a viable forage seed industry, the following may be listed:

286 Covercmps for naturalmom managemenf/Pantesde wwertureef gesliondes ressourcesnamfles

Table 4. Quantities (kg] of cover crop seeds distniuted by NAPRI (199S1998). Species

1995

1996

1997

1998

Lablab Verano Mumna Total

310

635

3895

730

Inconsistent and unsustained government policies Lack of technological support for forage seed production. Equipment for seed harvesting and cleaning are not available and facilities for training technicians in seed production are lacking. Manual harvesting of legume seeds is labor intensive, time consuming, and wastehl. Investigations showed that it required about 180 man-days to hasvest seeds from one hectare of S&ylosanthesI?amata and seed recovery was about 30% (Agishi 1985). Poor yield of seed, loss of viability in a humid environment, and law seed retention (shattering) of some specks.

Adoption of cover cropping Even though the beneficial role of forage legumes in farming systems is no bnger in doubt, their adoption rate has been chronically low. Apart from the use of cover-crop legumes in tree plantations, adoption of forage legumes by crop f m e r s is virtually nil even though recommendations for fitting forage legumes into cropping systems are available (Mohamed-Saleem 1984b). As reported by Norman et a l (1982), intercropping is more labor intensive and therefore the chances of the farmer adopting a cereal-forage legume intercropping system is probably not high unless he can derive some other tangible benefit at the same time. For example, it would be far easier to convince a farmer to intermop his cereals with edible legumes. in fact the practice of intercropping of cereals with grain legumes such as cqwpea and groundnut, is widespread in the subhwnid zone of Nigeria. Therefore the use of dual-purpose legumes (such as Lablab purpurars) as intercrops with cereals should be explored. One objective of intercropping forage legumes with cereals is to produce crop resihres of better quality for livestock However, one would note that agropastoralists are not likely to adopt such a system. The agropastoralists mainly cultivate sole crop cereals since their main aim is to produce enough grain for home consumption and there is usually strong competition for labor beween livestock and crop enterprises (Powell 1984). The adoption of forage legumes in farming systems has made the highest impact so far in the area of fodder banks. The fodder bank concept was developed by ERI

(ILCA) scientists of the subhumid zone pro=-, Kaduna in the late 2970s. It was designed to ease shortage of livestock feeds during the long (5-7 months) dry season. A land area of about 4 ha is cleared, fenced, prepared, and sown with a forage legume, usually Sty1osanthes spp. (Mohamed-Saleem 1984a). The resulting pasture of styld grass mixture provides more and better quality fodder than crop residue alternatives during the dry season. The system had some appeal to agropastoralists and there was a spontaneous adoption of the intervention (Elbasha et a l 1999). It was found that adding phosphate fertilizerwas necessary to achieve maximum growth of the legumes.. For example, maximum dry-matter yields of various species of Stylosanthes ranged fiom 5.5 to 9 f i a after application of 55 to 70 kg Pha (Agishi 1983). The fodder bank formulation was developed into an extension package administered by the National Livestock Projects Division (NLPD) of the Ministry of Agriculture and Natural Resources. The beneficiaries were mostly agropastoralkts who were to incur all costs. Credit was extended to the agropastoralistsby the NLPD to pay for the fencing materials, seeds, and fertilizers. The fodder bank project was vigorously promoted by NLPD and by 1990, the number of agropastoralists that had adopted the intervention exceeded 500. There were many constraints in the implementation of the new technology and thus the fodder bank program could not be sustained. Some of the problems encountered were (Taylor-Powell and Suleiman 1984). Lack of policy commitment and budgetary provisions for long-term development Hierarchical organization and s ~ crigidity ~ lof the administering government agencies Ad hoc planning with inadequate implementation procedures Limiting,or irregular supply, and Egh cost of.essentia1 inputs Inexperienced and untrained extension staff, resulting in ineffective field-level superrision. These problems have demonstratedthe need for more focused and realistic research that addresses itself to fmding solutions that are practical and that can be sustained. Perhaps the most urgent task is to identi9 the most relevant legume technology for each target zone and getting farmers to test and evenmlly adopt them.

Prospects for forage legume adoption Dramatic changes in W e r s ' attitudes towards legume adoption into the c m n t farming systems are not expected in the foreseeable future. The brightest prospects for forage-legume adoption lies in the closer integration of crop and livestock production systems and for this the subhumid zone offers the best environment. Most areas of-the zone are relatively h e of tsetse fly which is still prevalent in the humid zone whilst environmental constraints on agriculture are less severe than the semiaridlSahelian zone further north.

Country and network repaM&pporfs natimawr at du &eau 2$9

Taylor-Powell, E. and H. Suleiman. 1984. Extension implication of LCA's interventions: Dry season supplementation and fodder banks. Pages 382-390 in Livestock systems research in Nigeria's subhumid w ~ eedited , by R. Von Kaihmn, S. Chater, and R Blench. [LC& Addii Ababa, Ethiopia Young, A. and A.C.S. Wright. 1980. Rest period requirements of tropical and subtropical soils under annual crops. Pages 197-268 in Land resources for populations of the future. FAO, Rome, Italy.

Cover crop research activities in southeast Nigeria 1-EG. IReorgri National Root Cmps Resenrch I n s t i ~ eUmudike, , h t a h i q Nigeria

Abstract Very high population density has resulted in intense pressure on native vegetation in southeastern Nigeria. Cover cropping with herbaceous legumes is one way in which r e s e q e r s hope to protect the environment while still helping farmers to make a living. The bulk of the research is located in the National Root Crops Research Institute, Umudike, Abia State. A listing of researchers working actively on cover crops systems is given.

La forte densit6 ddrnographique a entrain6 une pression intense sur la vCgAation naturelle dans le sud-est du Nigeria. La production de 16gumineusesherbackes comme plantes de couverture est une m6thode que les chercheurs esperent pouvoir utiliser afin de protkger I'environnement et d'aider les agriculteurs A gkntrer des revenus. La plupart de ces activites de recherche sont menCes A 1'Institut national de recherche sur les plantes A racines et tubercules Umudike, Etat d' Abia. La liste des chercheurs qui travaillent activement sur ces systernes de plantes de couverture est jointe.

Location National Root Crops Research institute, Umudike (5027'N;7'32'E) is a zonal research institute for the southeasternagroecological zone of Nigeria. It is located in me middle of the humid rainforests and has an annual rainfall of b e m e n 1900 and 2200 mm (20 years average). NRCRl, Urnudike as a zonal research institute, is responsible for improving the total farming systems of farmers in the zone by developing and extending to them, appropriate, affordable, and acceptable food production technologies capable of improving their livelihood and well being. Southeast Nigeria (between 8 and 9" E, 4" and 7 O N)has a total land mass of78 6 12 km2,and has a population of over 18.9 million according to the 1991 census. The population density in this area is one of the highest in the world as some mas like h o

Cocv~tfyand network repoWRapports nafiunauxet du r&eau 291

State have as many as 404 p e r s o n h " m e pressure on agricultural land is so high

that the original forest vegetation has been removed in most places leaving wild oil palrns and secondary vegetation. Shifting cultivation witb long fallow periods was the dominant h h g practice until some 3 4 decades ago. At that time, land-use intensity consisted of 10-12 years of fallow to regenerate soil fer&ility,but today, fallow periods hardly exceed 3-4 years. The obvious result of this mustainable land-use system is soil degradation and soil erosion. Soil fertility is poor and the soil is acid (pH = 3.8-5.2). Some yam landraces have become extiuct because the soil no longer provides the type of fertility they require. The major starch staple now is cassava, which tolerates marginal soils. That is why the major research h t in this zone is soil fertility regeneration and improved land-use systems. The use of organic fertilizers is being emphasized such as the use ofIe,@minous cover crops, shrubs, and trees for soil: fertility regeneration as welt as multistrata cropping systems that ensure complete soil cover to control erosion and reduce weeds.

Cover crop workers in southeastern Nigeria At the end of 1998, the active cover crop workers were as follows: Dr J.E.G. keorgu, Agronomist, NRCFU, Umudike - Evaluation of leguminouscover crops for soil fertility regeneration and weed suppression in the degraded forests of SE Nigeria. - CCropnet Trial title& Evaluation of the suitability oftwo Mumnu varieties for soil:fertility regeneration and weed suppression in the degraded forest ecology of SE Nigeria. Dr A.O. Ano, Soil Scientist, NRCRI, Umudike Evaluation of the contribution of leguminous and cover crops to the conservation of the soil resource base and the productivity of cassava-based cropping systems - EiTect of vegetablecowpea population on the conservation of the soil resource base and seed yam yield in yam minisettlcowpea intercrop. Dr DA. Okpara (Federal University of Agricdtwe, Umudike), M i J..Njoku (NRCRI, Umudike) and ProE J.E. Aslegbu (University of Nigeria, Nsukka, Agronomists) Studies on cover crops in the lowland humid forest zone of SE Nigeria Growth and yield response of four mabe varieties to green manure sources - Response of two sweet potato varieties to green manure sources - Evaluation of the duration ofMumna fallow on growth and yield ofmaize - Effects of duration of Mucma fdlow on growth and yield'of two varieties of sweet potato

292 Cover crop br natural resource managemenl/Pantes de couvenureer gestion des ressources natueiles

Mr Anselm Udealor, Agronomist, NRCRI, Umudike Contribution of vegetable cowpea cover crop in nutrient recycling in cassavabased systems. This work is centered on the contribution of decomposing leaf litter from vegetable cowpea to soil nutrients. Mr Lawrence Owoeye, Soil Scientist, IlTA Onne (PhD student) Use of leguminous shrubs and cover crops for soil fertility regeneration in the degraded forests of SE Nigeria.

A regional experiment to test green manure cover crops and evaluate the role of Internet-based networkingq 'lntem~lional~mtihue o/71opimt~griaikw, i&a&n,Nigeria li~ntwnatid inrtituteof ~ i ~ i cA@a* l &on04 Benin

Land degra&&on in the West A6icm subregion is threatening the food security and Live~oodsof both n d and urban populations. Green manwe cover crops have the potential ofreversing such trends.A wide m g e of stakeholdeishave been involved h the promotion ofthesetechnologies and it became apparent that a network was needed to provide a common f o m whew these cover crop enthusiasts could discuss their problems and identify oppomrnities for synergy* With the advancement of-ICT (hfiormation Communication Techn010gy) it was also conceived that the use d hernet-based technologies would enhance such a sustainable research atid development program. It was against this backgmund that CCROFMX (Cover Crops Network) was formed in January 1999 b test these novel concepts. Funds for this network were provided by USAID. As part of this exercise, researchers are testing the contri'bution of two cover-crop species to s u s W 1 e agriculture and simultaneowIy evaluating the effectiveness of the Znternet in conductingsrrch a trial. Results so fixhave show &at ICThas potentid in promoting the quality ofresearch in the region, but some constraints have arisen, including technical and financial probtems with connectivity and unfamiliarity with h e use of e-mail sohva~e,ek. Continued efforts to alleviate these c 0 1 1 s ~ t and s encouwge exchange of i n f o d o a , especidy amongst peers, are recommended.

D m la sous-rdgion d'mque occidentale7 la d6grahtion des terra menace la skurib5 alimentdre et les moyens d'existence des populations aussi bien nzrales qu'urbaines. Les plantes de couverture utilisdes c o m e e n p i s vert ont Za capacitt! de reaverser cette tendance. Une vaste gamme de parties prenantes p d c i p e B la promotion de ces technologies et il est devenu evident que la mise en place d'un rkseau Tlris is IlTA manuscript number HTA/OO/CP/O4.

s'impose a& de disposer d'un cadre commun 03 les enthousiastes des plantes de couvertwe pourraient discuter de leurs problemes et identifier les opporhdtBs d y n e synergie dans ce domahe. Gdce aux progres de la techologie de communication et d'infomation (TCI), la possibilitd d'utiliser les technologies li6es A IY'lntern&a 6% perpe en w e de d o r c e r un programme de recherche et de ddveloppment durable. C'est dans ce contern que le Rdseau sur bs plantes de couvmme (CCROPNET)a W mis en place en janvier 1999 afin de tester ces nouveaux concepts. L'USAID a alloue les fonds pour ce reseau. Au titre de cet exercice, k s chercheurs menent achlellemeat des tests sur la contribution de ces dew especes de piaates de,couverhse A la dmbilitd de l'agriculture et &alum simultanBment lYefficacit6de l'hternet dans la realisation de ces essais. Les dsultats obkmsjusqu'ici ont montr5 que la TCI prdsente un potentiel de promotion de la qualit6 de la recherche dms la rt5gion, mais quelques contraintes oat dt6 identifides, notamment les problhes techniques et f%anciers lids aux possibilitds de comexion et au manque d'expt5rience en matiere d'utiZisatio11 des logiciels de c o d e r dlectronique. Il est reconmandB de continuer h fomir des efforts en w e de juguler ces contraintes et d'encomager un Cchange d'iaformations, out en* les coU8gues.

Land degradation is threateningthe ecological and economicsustaiaabii ofnatural resource lai1'mtioa throughout &Saharan AEria (Tian et aL 1995, Sanchez et al. 1997, Schm 1999). Direct implicatiox~sinclude a decline in crop and livestock productiv@, which thxeatms the food seam@ of both nnal and usban populatias (Jayne 1989, FA0 1998). Green mmme cover crops (GMCC) are among the most promising technologies to meet and reverse such challenges of land hpoveFishment for the n d pool: Research bas shorn &at these crops can be efficient sources of nitrogen, improve soil physical and biological propexties (Hulugalle et al. 2986, OseiBonsu and Buckles 1993, Saaghga et al. 1996, Carsky d al. 19983,he$ control pests and weeds (Akobmdu and Pokrt 1984, Versteeg and Koudokpon 1990, Eemer et al. 1996, Web= et al. 1995, MerkeE et al. 1999, Galiba et al. 1998)' and provide livestock feed (Mohamed-Saleem and Suleiman 1986, Wwa1i 2995, h e g b u et al. 2996, Tarawali et al. 1999b, Yai 1998) and additional income tbt.ough seed production ( T m a l i 1994, Agounke et al. 2996). The rise in adoption trends of cover crops in many West African corntries is a clear indication of their potential to contribute to the sustainabilityofA&ican agriculture(Manyonget al. 1996,Vissoh et al. 1998,Twwali et al. 1999a).

Many diverse entities including international and national research and extension organizations, universities, NGOs (nongovernmental ogaaktions), CBOs (community-based organizations), and f m e r groups are already involved in the effort to evaluate the various GMCCs ,and promote their use (Buckles et al. 1998, Elbasha et al. 2999). However, the very diversity of the people and organizations involved implies that these potential p m e r s need a common fonua within which to share problems and opportunities for synergy arising from the introduction of this promising option in sustainable agriculture. Such networking can he@ partners, who conhnt many similar problems and who can contribute complementary sldls, to achieve a common goal more quickly and effectively. Recent advances in information and communication technology (KT) oEer the promise of using Internet-based networking to help solve research and development problems b t e r and more efficiently (James and Rykert 1998). However, there is so far little experience k how this new technology can best be used in deveIoping comaies,where the idhstmcture is oRen we& and indeed, whether such a technology is at all appmpriate for such circumstances. h order to test these novel concepts, the I n t e d o n a l Institute of Tropical Agriculture @TA) with financial support h m USAID-Aficdink established the Cover Crops Network (CCROPNET) experiment in Januaty 1999 with the seaior author as its F ~ i t i t a t o r / C o o ~The r . Network and its experiment operate w i t h the h n e w o r k of CIEPCA (Cover Crops Infomation and Seed Exchange Centre fhr Afika), which aims to improve the eficiency of research and development act4vities of workers through information exchange md seed dkki'bution and by assisting in providing advanced information technoIogy hilities (emdhternet). The research agenda is implemented within the short f a o w systems(former Project 1, now Projects 1 1 and 12) of BTA's Resource and Crop Management Division (RCP6D). The idea was to set up by a group of researchers from NARES (National Agiculttd Research and Extension Systems), NGOs, TARCs (hternational Agricultural Research Centers), universities, etc. to test two Mumgprwiens varieties for theit abity to contribute b various s13stakhle nahrral resource management needs and simultaneously evaluate the use of Internet technologies in underpinning this networking effort The p m m t article reports the progress made during the first 6 months ofthe experiment.

Materials and methods CCROPEJET consists of two interlocking experiments, one in agronomy and one in. information technology, with a parallel purpose of evaluating methodologies tow& a common goal of promoting sustainable agricultural development,

Agronomic aspects Agronomic hypothesis (individualtrials}: Suitably selected species and varieties of green manure cover crops contri%utemore to restoration of degraded land than natural fdlows as measured by: - enhanced soil fertility (total and available N, soil organic m-, and subsequent crop yield) - suppression of noxious weeds (nuinbedbiomass of total weeds; estimates of Sniga seedbank, counts dImperata rhiimes) - production of high quality animal feed (total biomass; m d e protein content) Agronomic hypothesis (regional level): A model of cover crop phenology (driven by climatic data; Aiming et al. 2999) can describe the growth of M u c m planted across a wide diversity of sites in West N c a . Summary of methodology for agronomic trial. A summary of the experimental design proposed to network participants includes 5 m x 5 m experimental plots established on farmers' fields (or research station, if necessary), with thee to four replicates and at least I m spacing between plots 1). Land was tilled and the following treatments established: Mumna species Z ( M x c m p ~ ~ ~ r i va.. e i z sutr'li's} Munma species 2 (Mucunacochinchhenris) Control {natural fallow, i.e., weeds allowed to colonize).

Data to be recorded at each site Site characterization: latitude, longitude, altitude. Climate: daily rainfall, max./nin. temperature during year of experiment (normally available from nearby meteorological station). Phenolom: planting date, percent germination. Stand count and percent cover after 4,8, and I2 weeks. T i e to floweriag (50% plants flowering) Time to pod set (50% have set seed) Germination count and soil cover were measured by counting seedlings within a 1 inZquadrat and estimating soil cover. Pests/diseases: identie and assess incidmce/se~eFityof any major pest or disease ontbreaks observed. Incidence = the % of plants witbin the quadrat showing symptoms; severity = % of the infected plants that are damaged. Biomasslforage: plants withiin each of two I m2 quadrats within each subplot should be cut at a height of 20-1 5 cm and the Besh material weighed immediately. A subsampb of fresh material (150-200 g) will be accurakly weighed and oven dried to estimate dry matter production.

29m

< 0

19m

Sampling area (3 m x 3 m) for every plot Treatments: Mu = Mumna pntriens var. &is; Mc = Muwna wchinchinensis;Nf = Natural MOW

Figure 1. Experimentat layout The experiment should be established either on-stakion, or an farmers' fields. Farmen may well be preparedto set up and manage the plots themselvesif the objectives of the trial are arefully explainedto them and iftheya a able to bene@(e.g., by keeping the seed end fodder produced, beyond that required as samples, for their own use). Note that blocks do not need to be adjacent to one another (as shown in &e diagram) but m n even be on separate farms. Treatments (i.e., the two wver crops and the natural ;fallow)need to be assigned randomlyto plob within blocks. Do not simply follow the plan provided as a prescriptivepattern ar &is will invalidate the underlying statistical assumptions ofthe proposed analysis.

F o q e quality: determine total mde protein for biomass samples. Soil improvement:estimate total soil organic matter, total N,and available P and K ikom each plot. Wmd growth: biomass d weeds should be measured towards the end of the Wal period by cutting and weighing all the material within two il m2quadrats in each plot. Efforts should be made to i d m e the dominant weed species and to estimate the number of seeds of Striga (separatiodflaatation procedure) or rhizomes of speargrass in the soil in areas where these weeds are predominant.

298 C m r cmps (oralum1resource m a n a g e m e ~ l a nde t ~cowertu~ etgesiion des ressourees nahrrdles

Data analysis At the level of individual sites, records 1-4 are purely descriptive (see below for analysis). Variables 48 involve replicated estimates fiom each subplot and can therefore be subjected to ANOVA.

Networking trial Networking hypothesis: the capacity of researchers to contribute to the agreed goals of an agricultural development network can be enhanced (in a cost-effective manner) by the provision of Internet-based tools for information exchange. Methodology for electronic networking trial: experimenter members of the network (i.e., aose who will ac&aIly attempt to plant the field trial) are divided into three groups, according to their access to e-mail: - Group 1 (GI)comprises established users with access to e-mail [with an additional subcategorization, depending on whether the network member has their own e-mail facility (G 1/P)or only access to a shared computer and mailbox (GZ/S)J. - Group 2 (G2) comprises those newly connected (assisted by the project). - Group 3 (G3) comprises those having no e-mail access. A fourth group (G4) comprises network members who are either nonexperimenting expert resource persons or 0bse~ers. Analysis will be based on comparing various measures of "erfomance" of experimenters between groups, especially basing the assessment on the completeness of the damet reported at the end of the triaYseason. (The several variables will allow a gxaded assessment of response). Criteria will include not just the number of data sets but also "quality control". For instance, was there adequate replication? Was data analysis performed correctly? Evidently, there is a danger of "compounding" of factors. Experimenters in Group 1 may not only differ &omthe others shp1y h theiremail facilities, but there may be other factors. For example, they may have better resources in general taan those: in Groups 2 and 3. However, careful description and analysis of information and site visits will he$ to ensure that the comparison is still valid. Supplementary data will be collected on members' use of netvrork resources. For instance, pests sent for identification, queries posted to more experienced cover-crop experts, and their contribution to $he group, such as in terms of responses posted to the enquiries of otbea. The network hilitaior will dso attempt to document more openended measures of particwon: how did experimenters assess pest and disease outbreaks? Did they seek advice on how to assess the severity of such outbreaks or seek help in identification of xhe orgaaisms concerned? Did they seek advice on sampling or statistical procedures? +

CountryandnetwwkrepmiMapports natratrmauxef du r&ea 299

Did they contribute advice, reports, and responses to the electronicdiscussion f o m or communicate with other network members by m i l ?

Cost &dveness Among those experimenters deemed to have "completed" the field experiment in a "satlsfactoryv' manner (exact measures to be decided, but based on reporting of a useful data set), the fac5iator will attempt to compare the costs of providing technical support by Internet-based and conventioaal means. In other words, those who completed the experiment will be wnsidered to have received "adequate" support fiom the network: how much did it cost to provide this support by conventional or ICT-assisted means?

User pemptions Structured questionnaires wiU be used to assess the reaction of the experimenters to their participation in the neiwork, e.g., did they feel that participation in the network had contributed significantly to their eEectiveness as researchers? What, if anything had they learnt? Were they satisfied with the nature of support provided by resource ~encountered? t This aspect s is persons andlor by their peers? '#hat were the ~ very important because c e W members of the network have had direct contacts with other colleaguedexperts who are not members of the network but have identified similar areas of research interest through CCROPNET.

By the end of January, a workplan with a specitic time M e was developed. Also, hvitation letters, a concept note, and membership forms were despatched to over 80 potential members and by March, over SO researchers (serislc lafo)had accepted the invitation to participate in the network. A provisional design for the agronomic experiment was developed in MarcWAppril 2999, including testing of two M u m a prwiem varieties against a natural fallow control in replicated field plots. The experhenid protocol, modified according to comments made m a y electronically by participants, was finalized by the end of June 2999. In MaylJune the Facilitator undertook a tour of West Aiiica involving Benin, Bdciina Faso, Ghana, and Togo, to supply Muc2u1a seeds (seeds had to be delivered to ensure they all had comparable material) in readiness for planting, to evaluate email fkcillties, and encourage members to play an active role in the network

300 Coverdropsfor na~mlresa~~~~managemenVPIantes de wwertumetgesb'mdes mourcef na?mRes

discussion. A similar exercisewas conducted for Cameroon, C6te d'lwoire, Guinea, Mali, and Senegal. The major activities included supply of materials, discussion of the experimental protocol, and encouraging participants to freely participate in the network discussions Rehctance to conduct the trial without a formal agreement between IITA and some NARS was also expressed by some co'ilaborators but the issue was partially resolved by following-up with appropriate letters to our national counterparts. Lnability to conduct the &id was hsome cases due to the fact that all h d s had been committed by the N k R S and there was no extra money to establish another activity* An informal assessment suggests that a large number of trials have been planted (about 30, Table 1) by as many network members as possible across a wide range of sites in West Aftica (Figure 4). Preliminary experimental data from 4 locations is given in Table 2 as an example of a comparison of Mucuna varieties across sites and countries for some parameters. The results show that the gemination of the Mxcuno varieties in ail tbe 4 sites was very good (> 80%) and the % cover, even 8 weeks after planting, was very high. The number of days to 50% flowering at all the sites was more than 87 days (Table 2). Except for Burkina Faso, Mamna cochinchinemis seems to have an edge over M~mnapmriensvar. utilis in terms of rate of establishment. Some of the pests and diseases observed included virus mottling (Nigeria-Ibadan), bud damage (NigeriaOnne), flower abortion (Ghana), and locusts in Bwkina Faso. It was interesting to note that while there was complete weed suppression at ibadan (Nigeria), Pcminrm became the most persistent weed at Onne (Nigeria) and Accra (Ghana). It is as yet too early to discuss the reasons for the similarities and differences in observations amongst the sites but this could be related to the agroecologicai zones represented in the trial.

Progress on electronic nehorking trial The connectivity status, needs, and potential of network members were assessed and each member was provisionally assigned to the groups previously mentioned [i.e., already have access to e-mail (50), newly connected (31, unconnected (I4), and resource persons (2913 (Figure 3). During April, both tbe network Facilitator and the AfiicaLink Advisor (Dr Jeff Cochrane) visited some key network sites in Nigeria and individually visited various network members elsewhere to assess connectivity needs and progress to date. At the conclusion of the Advisor's visit, revised project documents were drafted in discussion with IITA staff (activity coordinated for IITA by the second author). By April 1999, the West African Cover Crops Network {CCROPNET) List-Server

nationam et du meau 301

Country and nefwork1 e - m

Table q. Total number of participants and trials in each country.

Country Benin Burkina Faso Cameroon C B k d'lvoire Gabon Ghana Guinea Mali Nigeria Senegal Toso Total

Confirmed number of trials

Expected number of ivials

No. of participants

in brackets ( ) are additional to trials established by internationat centers (C Wh).

M -

Table 2. Cross crruntry comparison of the performance of Mucuna using selecied parameters. LaiiiudULongitude Date of planting

% Germination

Days to 50% flowering InadenceofpesW diseases

Weeds

Nigeria (lkdan) 7%)' N. 3-54.E

Nigeria (Onne) 4 9 N. 793' E

14/06/99

07/07/99

Ghana (a) Burklna Fasa (Saria) 12"16' N. 209' E 02107199

558' N. OD18' E 24/06199

100

>90

>I24 >124

s87

>87

Virus mottling

Bird damage

(24%)

- CompIeb

suppressionof weeds

Mostweeds suppressed. except P m m

Morefbwering abortion

Mastweeds suppressed except Paruarucllm

Locusts

Few

(25%) l~cusis

Nf = Natural fallow; Mc = Mucuna caehinchinensis; Mu = Mucma p ~ f l e n svar. utilis.

was setup with CGNET.Twenty-eight participants were subscribed on I 1/04/99and this list had risen to over 60 by October 1999(Figure 2). A welcome message was sent to aU participants and this was followed up by the posting of the proposed experimental design on the network for discussion on 26/04/

99. Useful suggestions/interventionswere immediately contri'buted, leading to some modification of the experimental design. Participants with access to e-mail have begun to report p h t i n g of ihe 21&h over the network as well as some prebinary data (gemhation rates, stand establishment etc., Table 2). It was encouraging to note that the electronic discussion, which started with about 16 messages in May, has currently risen to 107and about 40% of the con&'trutions: have

302 Cover m p s for natural resource managemenVPkntes Ue cauvetiur~et gestion des ressoums naturelies

members in 0 1 wfih accessto

Ii n d ' i a ! e-ma8 faeil'i Figure2 Cumulative number of subscribers to CCROPNET 4 t h time.

Figure3. Connectivity status of CCROPNET . participants.

come ticom NARS and NGOs (Figure 5). The higher intervention(about 60%) &om IARCs could p d y be related to the &ct that most of them have personal e-mail boxes. Our objectivein thistrial was to provide improved communicationfacilitiesfor less privileged participants but ody a few new comections were made before the commencement of the trial d electronic discussions. Out of the 25 participants that w m earmarked for connection, ody 3 have obtained e-mail facilities &rough CCROPNET.Twelve are awaiting funddequipment and 10 are yet to submit their profomas to the CCROPNET facilitator (Table 3). According to the agreement with out donor partners, a participant &omNARS is supposed to moderate the discussions. We have identified a moderator but he has so far not been able to take up an active role because of technical problems. h the meantime, the moderator's hction is peifonned by the network Facilitator to ensure &at active information exchange is sustained

Discussion From the above r d t s , there are very positive indications that the use of information techotogy to promote research on sustainable agriculture in the West African subregion has tremendous potential, even though some constrahts have been encouatered

Some of the positive aspects ofthis study are as follows: The establishment of a f o m q bringing together a wide range of research and development organhtiom and empowering their staff with facilities to participate,

Figure 4. Dishibutionof experimental sites in West and Central Mca.

has given an opportunity for trials conducted by well-reputed researchers to be validated (in collaboration with farmers) or exlrapolated into a wider domain, thereby increasing the chances of adoptidimpact. Although it is too early to make rapid conclusions, it appears (Table 2) that the results &om this exercise will assist in verifying some issues such as whether Mucwza establishes well in a wide range of environments (Smginga et al. 1996). Not much can be said about validating the M z m n phenology model at this stage because the plants at many sites have not yet reached the 50% flowerhg stage. It was encouraging to note that betureen January and April 1999, about 85 members completed and returned their membership forms as evidence of reatering their support for the network. On the same note, it was satiseing to ackuowMge that out of the proposed 55 fMs, researchers have confirmed the e s t a b b e n t of 28 experiments and more than 80% of these we= by NARSMGOs using thek own ~ e s o u meven s when most participants did not make provision for this in their 2 999 Table 3. Actions tdken towards connecting CCROPNFT members. Attian

Number

Awaiting Pmbrma

Awaiting fundslequipment

New conneetees (assistance varied from supplying modem to completeequipment) TOW

3 25

3W Covercrop br natural rwource managemenfllanfesde cpmrtrrreetgestion Ues ressoun:es nafureIIes

Figure 8. Contributions by NARSNGOs and IARCs in CCROPNFF electronic discussions.

budget allocations. T?&s high number of trials could not be achieved with one growing session iu a conventional network. The planning, discussion, and finalization of the experimental desiga and the implementation of the trial all took place without having to hold fxe-to-face meetings typical of a conventional network. This has definitely saved time/ resources and is a new development in conducting research in West Afkica. Before the commencement ofthe trial, some observers anticipated that there would be no need for the involvement of e-mail wtil the reporting of data after the final harvest, making this forum similar to a conventional network. Hawever, issues developed during the planning, discussions, and course of the trial that required immediate clarification. For instance, planting distance, the easiest way of making gemination counts, cutting height, and whether the experiment should include an established or new fallow were all issues that were quickly resolved over the e-maiL It is obvious that if such u n c d t i e s can be resolved through e-mail, this could bad to a more dunifom Isidand hence more reliable results. Experimenters without access to quick means of commuaication are obliged to use their discretion, perhaps making modifications that could lead to a high degree of variation. Finally, there were a lot of participants who gained either directly or indirectly from the network discussion, through the exchange of information, matwials, and establishment of linkages with other scientists: one even gained admission to a British university through links established on-line. A non-CCROPNET researcher who h o w s about our activitiesthrough a network enthusiast, offered his 4 years of Mumna data to be included in the phenology model.

Some of the underiying constdnts encountered include the following: Project impIemeniaiion is still constrained by lack of a formal agreement between the project implementation partners QITA and USAID) which has prevented DTA from committing adequate resources to the project. No further progress on connecting new network members or establishing a web site can be anticipateduntil this basic agreement is in place. A direct effect ofthis slow rate ofrecruiting newly connected members is that the number ofparticipantsin this group may not be large enough to justify their inclusion in the statistical analysis. Potential experimenters in two national research organizations in West Africa cited the hck ofa f o d Memorandum ofUnderstanding(Mow between IITA and their respective governments, specifically covering the CCROPNET experiment, as a constraint preventing them from planting the field trial. Attempts are being made to remove this cons-t, but any progress is likely to come ioo late to allow these particular trials to be planted in ihe current season (Table 1). An additional factor is that responses from network members, either though e-mail or other means, io requests made by the network facititator have sometimes been very slow, leading to delayed action in w e n t matters. As shown in Table 3, many participants are yet to send their proforma invoices in order to address their e-mail requirements. The constraints preventing the agreed (NAB-based) moderator fronz taking on his responsibility in reelation to the electronic conference are not., at this h e , fulIy understood. Overall, network members have expressed and demonstrated great enthusiasm for partkipation in the C C R O P W experiment. However, in most cases, elecmnic communication with other network members has been very limited. Techical and fmncial problems with connectivity appear to be a constmint in most cases. However, it seems that another major problem is unfamiliarity with the e-mail medium and its informal communication culture. Efforts will continue to be made in order to remove these constraints and encourage the free exchange of i n f o d o n including further discussion at the current workshop. In accordance with the agreement with the donors, an interim report has been submitted and a web site will soon be developed. The development of a web site has been delayed by available staff time/resources. The faciIitator will attempt to gather the results ofthe trial into a publishable form--effectively workshop proceedingswith individual papers from each experimental site, authored by the responsible network participants, and joint papers describing the electronic networking experiment and the model validation. The proceedings will be published on tfie network's web-site and (if h d s permit) in printed form. if suEcient participants contribute a usell data set, the model validation and/or resuits of the networking

experiment may be published in r e k e d journals. Other results will be reported through the normal in-house publications of USAD and mA. Lastly,and not in any way the least, dissemination of useful technologies should reach grassroots farmers through various extension channels such as NGOs. la this regard, publications such as leaflets, audio-visual materials, manuals in several languages, and other extension materials will be useful. iiTA could assist in the production of the extension materials.

Conclusions Promotion of cover crops through networking aided by ZCT has tremendous potential in boosting sustainable agricultural production In sub-Saharan A f k a Areas to be emphasized in &re w l l include the creation of more awareness of the advantages of cover crops amongst NGOs, network members, i%rmers, and policy makers. Also, for effective communication through e-mail, more effort should be made in improving the facilitiesof most aeWor2Emembers. Finally, collaboratonhave to be encouraged to get used to the idea of cornmicaXing through the e-mail hfomally and exchanging i d o m d o n freely in order tct klly expiok the benefits associated with this technology and especially the peer-to-peer networking &at it can ideally facilitate.

References Agounke, D.M.Ossekou, G. Kolani, A. Ehlo, #. Bossou, and K Fantchede. 1996. Rapport dyexperiment&ionessai cornparatif de production de gmines de Mumno. Campagne 19951996. Station expmimmtale de DW-Davie, Lame,Togo. Aiming, Q., RH. Ellis, I.D.H.Keatinge, T.R Wheeler, SA. Tzwawali, and R.J. Summerfield 1999.DiEaences inthe effects oftemperatureand photoperiod on progress to floweringamong diverse Ikfumnaspp. Journal of Agnmomy and Crop Science 182: 24S258. Akobundu, 10.and 3.A. Poku. 1984. Control of lmpmta cyfindrica Pages 175-176 in DTA Annual Report, 1983. IITA, Ibadan, Nigeria

Bemer, D.K.,RJ. Carsky, K.E. DashieH, 3. Kliog, and V.M. Manyong. 1996. A land-management based approach to inkgrated Shiga hemonBica control in sub-Saharan Africa Outlook on Agriculture 25: 157-164. Buckles, B., A Eteka, 0. Osiname, M. Galiba, and N. Galiano. 1998. Cover crops in West Africa: contributing to sustainable @culture. lDRC (International Development Research Centre), Ottawa, Canada; IITA Ibadan, Nigeria and Sasakawa Global 2000, Cotonou, Benin. 29 1pp. Carsky, RI., S.A. Tarawali, M. Becker, DO. Chikoye, G. Tian, andN. Sangins 1998. Mucuna-

herbaceous cover legume with potential for multiple uses Resource and Crop Management Research Monogmph No. 25. IITA, Ibadan, Nigeria. 52pp.

398 W r c r o p sf o r n ~resource l rnanagmnenVPIantesde couwrtureagesfion des resources namnes

Tamwali, G.,YM. Manyong, RJ. Carsky, E? Vissoh, P. Osebbnsy and M. Galiba 2999a Adoption of improved fallows in West AEca: lessons leamed from the velvet bean and styio case studies. Agroforestry Systems 47: 93-122.

Tarawali, S. A. 1994. Small-scale forage legume seed production with options for limited resources. Pnoceedings of the RABAOC (Recherche en Alimentation du Betail en &we Omidentale et Centrale) workshop April 1994, Conakry, Guinea Tarawali, S.A. 1995. Selecting and testing Stylosantks hamafa accessions for livestock and crop production enterprises in subhumid Nigeria. Australian Journal of Experimental Agriculture 32: 375-379. TarawaIi, S.A, M. Peters, and R. Schultze-Kr&. 2999b. Selecting and testing forage legumes for sudnable agriculture and livestock production in subhumid West N c a . ILRlProjed Repo* ILW, Nairobi, Kenya 132pp. Tian, G., B.T. Kmg, 1.0. Akobundy and V.M. Manyong. 1995. Food pmducrion in moist savannas of West Africa. Pages 107-127 in Moist SavannasofAi3ca: potentials and constmints

for crop production, edited by B.T. Kang, I.O. Akobundy Y.M. Manyong, RJ.Carsky, N. Sanginga, and E.Kueneman. IITA, Ibadan, Nigeria, in c o o p d o n with FAQ, Rome, Italy. Veisteeg, M. and V. Koudopkon. 1990.Munrna helps control Imperlitli in Southern Benin. West &fan Farming Systems Research Network Bulletin No.7: 7-8. Vlssoh, P., V.M. Manyong, RJ. Carsky, P.Osei-Bonsu, and M. Galiba 1998. Experiences with M m n n in West a c a . Pages 2-32 in Covm crops in West Africa: contributing to sustainable agriculture, edited by D. Buckles, k Eteka, 0. Qsiname, M. Galiba, and N. Gatiana. D R C (International Development Research Centre), Ottawa, Canada; IITA, ibadaa, Nigeria; and S&wa Global ZOOO, Cotonoy Benin. Wetter, G., K. Elmo, A. Awaro, S.T.O. tagoke, and S. O i h . 1995. Shiga hermonrhica @el.) Benth. inthe croppingsystemsofthe northem Guinea savanna Resource and Crop Management Division Monograph No. 19. In&madm Nigeria

Yai, ?A. 1998. Experiences du projet de developpement de I'elevage du Borgou-est (PDEBE) sur les plantes de couvature. Page 239 in Cover Crops in West Africa: contributing to sustainable agricuiture, edited by D. Buckles, A. Eteka, 0. Osiname, M. Galiba, and N. Galiano, IDRC (International Deveiopment Research Centre), Ottawa, Canada; frTA, fiadan, Nigeria; and SasakawaGlobal 2000, Cotonou, Benin.

List of participantslliste des participants Firmh Amadji hg6niew Agronome

Wale Adekunle Public Awatertess Publications Coordinator IITA, PMB 5320 badan

MRAB BP 226 Bohicon Republique du B6nin

% ?! (229)510005

Nigeria

8 (229)510005

B(234-2)2412626 8 (234-2)24 12221 w.adekunb@cgiar.org

fadegon@syfedbj.refer.org Jiirgen Anthofer

Kingsley Adeoye Soil Scientist Dept. of Soil Science, ABU,Zaria Nigeria ccropiar@rcl.nig.com

SFSP c/o GTZ PO Box 473 Sunyani Ghm B00233-61-27376

Kokou Ahomton Ingdnieur Agronome 08 BP 0932 Tri Postid CIEPCAIEIA cotonou Rdpublique dtr B6nh 7% (229) 350i88 (229)350556 @ciepca@cgiar.org

James Y. Asibuo Agronomist CRi PO BOX3785;Kumasi Ghana 233-051-60242 =Jpobonsu@phana.com

IAR

Kouessi K i o u hg6nieur Agronome CRA-NiaoulBP 03 Attogon Republique du Benin (229)371 I50/371250 8 (229)300736 ~3 imabdg4@bow.intnet.bj ~ u e ~ IngBnieur Agronome INMJ.3 BP 584 Catonou R6pubIique du Benin B(229) 371150 8 (229) 300736 J& $ *habdg4@bow.hbet.bj

Maria Ayodele Co~ultant,GHU Unit

11x4

PMB 5320, badan Nigeria

B(234-2)24 12626 (234-2) 2412221 $ S J m.ayodele@cgiar.o~

Viceat Boubid Bado Agronomist INERA-Farakoba BP:910 Bobo Diouhso Bmkina Faso B973378

8 970960 vbado@fasonet.bf

Robert J. Cmky Agmomist ZITA

OS BP 0932 Tri POW Cotonou R+ublique du B e ?!?? (229) 350188 8 (229) 350556 ecarsky@cgiar.org

David Chikoye IITA PMB 5320, Tbadm Nigeria B(234)-2-24 12626 B (234)-2-24 12221 gd.chikoye@cgiar.org

Elie DembtSltS CrnT AgropastoDivision Dkfmst: et Restauration des Sois BP 1 Kodala Mali ???(223) 640103 8 (223) 640155 g CMDT-Koutial@spider.tooh&-org Seydou D i h k Agroforestier ADT-GERT BP: 416 mes Sknkgal =Adt-g&@mda.sn

Friday Ekeleme Research Associate

Albert Chabi Etkka Inghieur Agmome 08 BP 0932 Tri Postal Cotonou Rdpublique du BtSnin '?% (229) 350288 8 (229) 350556 ac.eteka@cgiar.org Ambroise Fantchddk ingenieur Agronome ICAT BP 20804, Lome Togo (228) 253773 8 (228) 254249 frnbreyBO@hotmail.com

Frands A. TUOF Weed Scientist SARI, Box 52, Tamale Ghana (233)-71-23251 (233)-7 2 -23483 S J SARI~caonline.com.gh

Fatou Gueye Assistante phytotecbnie ISRAICDH BP 3 120 Dakar Skn6gal e ( 2 2 1 ) 8350610 B (221) 8350620 S J fatgueye@son&el.srnet.net

XITA PMB 5320, badan Nigeria B(234)-2-24 12626 8 (234)-2-241222 1 f.ekeleme@egiar.org

John E.G.Ikeorgu NRCRI, Umudike Nigeria '?%(234)-082-44047 2/473 Hephfa@aol.com, qhta@iou.eb.abs.net

Em.mnuel N.0.Iwwfor Soil Scientist Soil Science Department IAR, M U ,Zaria Nigeria E-mail:eiwUafor@abu.edu.ng

Dyno Keatinge Agronomist DTA P ? B 5320, %adan Nigeria T!? (2341-2-24 12626 & (234)-2-24 12221

@d.keaibge@cgiar.ors.org Albert C. Koloboe hgenieur Agrmme

CARDER-.%acorn BP 32 Natithgou RGpublique du B6nin

%(229) 822006/80 & (229) 821200 Richard Markham P M Coord.imWr UTA PMB 5320,Ibadan Nigeria B(234)-2-2412626 8 (2341-2-241222 1

ffZJr.markham@cgiar,org

Jean-We Mewou hg. Agmeconomist GREPTG-ON(; BP 33 1 Cotonou Republique du Bdnin

'??f303303 Anne Mooahead IlTA PMB 5320, I b a h Nigeria

B'(234)-2-2412626 GA (2341-2-24 2 2221

~amoorheaa@c~~org

Joseph O m a Ecologiste IRAD-Garom BP. 42 5 Garoua Camerom B(2371 273171 8 (237) 272139

Olufemi S. Onifade Forage Agronomist NAPEu, ABU PMB 1096, Zaria Nigeria (2341469-550446

aonifade@abu.edu.ng

Patterson Osei-Bonsu Agronomist

CR? Box 3785, K w w i

Ghana

F?(233)-5 160282 & (233)

5160412

=a pobwsu@gha.com B a b m d e Oyewole Research Associate ITA PMB 5320 badan Nigeria

ST (234)-2-24 12626 18 (234)-2-24 I222 1 @t.oyewole(@cgiar.org

312 Cawrmps for nafutalresource managemsntrPlantes de camrtureet gestion des ressomes nalurelles

Jean Mianikpo Sogbedji Post doctoral Res. Assoc. MOISTICornell 1005Bradfield Cornell University Ithaca, w USA B(607) 277-4279/255-1706 (607) 255-861 5 Hms72@Comell.edu

Gbassey Tarawali CCROPNET Facilitator IITA PMB 5320 ibadan Nigeria (234)-2-24 1-2626 B (234)-2-24 1-2221 ~g.tarawali@cgiar.org

Olivier Vigan hgknbur Ago-Zoothecnicien IbRAB Bohicon BP 226 Bohicon Rdpublique du Bknin %(229).5 10005 Piere V. Xssoh Agronome SG2000 04 BP 209 Cotonou R&publique du BBnin B(229) 300459 &% (229) 300637 ~sg2OOOb@mtaet.bj

Guanglong Tian IITA PMB 5320, h d a n Nigeria B (234)-2-24 1-2626 (234)-2-24 1-2221 Hg.tian@cgiar.org

Jean K. Totongnon IngtSnieur Agronome CARDER-Atlantique Recherche-D6veloppementat BP: 22 Zmvi6 R&pubiiquedu Benin ???(229) 360072 mcardatl@inmet.bj Bernard Yanlauwe Soil Scientist IITA PMB 5320, Ibadan Nigeria B(234)-2-24 12626 B (234)-2-24 12221 ~b.vanlauwe@cgiar.org

Alphonse Youri Agronorne IRAD-Garoua IRAD, BP 4 15 G m u a Cameron f?? (237) 273 171 B (237) 272333 Robert B. Zougmod Agronome INERA 03 BP. 7 192 Ouagadougou 03 Burkina Faso '?%(226) 440042 (226) 34027 1 rob~zougmore@mess~~.gov.bf

Mensah Komouho Agbemelo-Tsomafo VeterinairPZootechnicien Universitc5 du BBnin

ESAfOB BP 1515 Lome Togo ?%(228)254 197/268624/220342

& (228) 218595 ?@?komagbe@syfed.Q.refer.org

h a d u Bello University,Zaria

Association pout le promotion de lYElevageau Sahel et en Savanne ARI. Animal Research Institute (Ghana) Association des Volontaires Togolais pow le D6veloppement AVOTODE CARDER Centres d'Actions Rbgionales pow le DBveloppment Rural CBOs community-based organizations Comitd dr: Conemtion CC CCROPNET Cover Crops Network Centre de Formation Ago-economique CFAE-SOS CGNET C G M Network Centro International de Agriculaua Tropical ClAT CIEPCA Centre d'hformation et d'echanges sur les plantes de couverhre en AEque (Center for information and exchange on cover crops in Africa) Centro Intemacional de Mejomiento de Maiz y Trigo (hternational Maize and Wheat Improvement Center) Centre de Coopet.ation Intermationale en Recherche Agtotlomique pour b Dhelappement (France) La Compagnie Malieme pour le Ddveloppment des Textibs CMDT Centre National de Recherche Agronomique (CGte d'Ivoire) cmw Centre de Recherche Agriwle Littoral CRAL CRC Catholic Resource Gem (Nigeria) CRI Crops Research institute (Ghana) DrnP Diocesan Agricultural Devebpment Project (Nigeria) DDRS, CMDT Division de dkfense et restamtion des sols, Cornpagnie malieme de d6veloppement de coton (Mali) DDS Diocesan Development Services (Nigeria) DMY dry matter yield ESANNB Ecob Superieurt: d'Agronomie/Univm&&du B W (Togo) ESPGRN Equip progrimme q*es da production d g d o n des resources natmelles (Mali) Groupe dyActionet de Rdflexion sur L'Environement et Ze DBwloppment Gemplasm Health Unit APESS

GIC GMCC GMT GREPID

u c s ICAT

KT IER FDC-A IlTA ILRI MERA

lSRA

ITIUI JAS LEXSYS MOW NAFCQN NAOCL NAPRVABU

Groupes dYInitiativesCommunes Green manure cover crops Greenwich mean time Groupe de Recherche et de Promotion des Innov&om de Developpement Durable (Benin) Deutsche GeseIlschait Air Technische Zusammenarbeit ( G e m Agency for TecMical Coopedon) Heifer Project International (Cameroon) Whzte for Agricultural R e s w h l M u Bello University (Nigeria) international a g i - i d d research centers M t u t de Conseil et d9ApprriTechnique Momation and Communication Technology Znstitut d'economie male (Mali) International Fertilizer Development Center-AfErica Laternational Institute of Tropical Agriculture (Nigeria and Benin) Znte&onal Livestock Research M M e M t u t de 1'Environnement et de Recherches Agricoles (Btdsha Faso) InstiM National de la k c h e n h e Agricole du Bdnln (Benin) Institut de Rechenks Agronomique pour le Ddveloppement (Came~y~on) Mtut des Recherche Agriwle de Guhee (Guinea) Mtut de Recherche pow le D6veloppement (France) h&ut SdnPlgdais de Recherche AgricoldCentce pour le D6veloppement de I'Hortlcuh Institut S6t16gdais de Recherche Agricole Lnstitut Togolaise de Recherches Agronomique jour ap& semis Legume Expert System Memorandum of Undemding National Fertilizer Compaay ofNigeria (Nigeria) N i g e h Agip Oil Company Limited (Nigeria) National Animal Production Research Mtute/Ahmadu Belk University (Nigeria) National AgricuIhd Research Project National Agriculaval Research Systems nongovernmental organkatom

m C R T

National Root C~opsResearch Institute migeria) O@ce 'National de D6veloppement R d ONGs organisations non gouvememen~les ONGFID Femmes initiatives Developpment OOAi3P Oyo-Osogbo Diocesm AAgridtrna1 Programme (Nigeria) PAT Potential AgrodEznopphique des Terres PJAE Projet httsgration A~'~ltureiE1evage de I'Extr&rne-Nmd m A FVogmme Nationd de Vulgarisation Agricoles PODV Projet &Organisation et de DB~eIoppementVillages pogo) PRASAC P8k Rdgional de Rechmches Agricoles Appliques a m S a v m e d9A&jueCenmle RAMAR Recherche AppIiqutSe en Milieu Reel Resource and Crop Management Division @TA) RCMD m M Y root dty matter yield RSUST Rivm State University of Science and Techology (Nigeria) $ A m Senrice d'Appui aux hitiatives Locales de DdveloppementApe (Cammoon) SARI Savanna Agriculture Research Institute (Ghana) SODECOTON Societd de Developpmetlt du Coton SG 2000 Sasakawa Global 2000 @enin) SPDC Shell Petroleum DeveIqment Company Wigeria) SUM Sudan United Mission (Nigeria] UDS University for Development Studies (Ghana) UNAAB University of Agriculture, Abeokuta (Nigeria) UNB Wnivemit6 Nationale du BeSnin pogo) wnive~sityof norin (~i'geria) UNILoRm USAD United States Agency for International Developmmt WARDA Wea AErica Itice DevelopmenE AssociaEion (C6te d'Ivoire)

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