Demand-Driven Technologies for Sustainable Maize ... - IITA

169Effects of sole cropping, intercropping androtation with legume trap-crops on Strigacontrol and maize grain yield in farmers’fields in the northern Guinea savannaI. Kureh 1 and A.Y. Kamara 21Department of Plant Science, Institute for Agricultural ResearchAhmadu Bello University, Zaria, Nigeria2IITA, Ibadan, NigeriaAbstractOn-farm trials were conducted in 2001 to 2003 in the northernGuinea savanna of Nigeria to evaluate integrated Striga hermonthicacontrol methods under farmer-managed conditions. These includedintercropping a Striga-resistant maize variety with cowpea (Vignaunguiculata L.) and also cropping this maize in rotation with legume trapcrops– soybean [Glycine max (L) Merr.] and cowpea. IntercroppingStriga-tolerant maize variety, Acr. 97 TZL Comp. 1-W, with cowpeaor rotating it with the soybean cultivar TGX1448-2E) or the cowpeacultivar IT93K452-1 proved effective in reducing Striga incidence andinfestation compared with three years of continuously cropped maizeas control. Striga incidence was reduced by 73% in intercropped maize,64% in maize after two years soybean, and by 68% in maize after twoyears of cowpea than in continuously cropped maize. However, maizegrain yield was considerably reduced when intercropped with cowpea,probably due to competition from the cowpea crop. Maize grain yieldwas 28% higher after one year of soybean and 21% higher after oneyear of cowpea than in the continuously cropped maize. Maize grainyield was 85% higher after two years of soybean, and 66% higher aftertwo years of cowpea than in the continuously cropped maize.RésuméDes tests en milieu paysan ont été conduits de 2001 à 2003 dans lenord de la savane guinéenne au Nigeria, pour évaluer les méthodes delutte intégrée de Striga hermonthica dans les conditions de gestion del’agriculteur. Ces conditions incluaient une variété de maïs résistanteà Striga, var. 97TZL Comp.1-W, cultivée en association avec le niébé[Vigne unguiculata L. (cultivar IT93K452-1)] et la rotation de culturede maïs avec le soja qui est une légumineuse - culture piège [Glycinemax (L) Merr. (cultivar TGX1448-2E)] ou le niébé. L’association de