Evaluating the Effects of Staking and Planting Dates on the Yields of African Yam Bean, Sphenostylis stenocarpa in Nigeria

Field experiments were conducted at Ebonyi State University, Faculty of Agriculture Research Farm Abakaliki, Nigeria during 2009/10 growing seasons to evaluate the effects of staking and planting dates on the grain/tuber yields of seven accessions of African yam bean (Sphenostylis stenocarpa, Hochst. Ex. A. Rich). The results indicated that all the African yam bean accessions performed better when they were staked and planted earlier in May of each season with greater grain/tuber yields, which differed significantly (P < 0.05) from those that were not staked and planted later either in June or July of each season. Of all the accessions assessed, TSs86 was the most productive with the highest grain yield and differed significantly (P < 0.05) from the rest of the accessions, while TSs84 had the least grain yields. Results on the tuber yields showed the same trend in relation to the treatments. The tuber yield showed that some accession could produce above 2 tons of tubers per hectare; however tuber yield showed inverse relationship to that of the grain yield across the accessions with the highest tuber yield was recorded in TSs93 and least in TSs86. In conclusion, for increased grain/tuber yields of African yam bean in Nigeria, it has to be staked and planted early in the season.