GERMPLASM CHARACTERIZATION OF AFRICAN YAM BEAN FROM SOUTHWEST NIGERIA

Thirty-two African yam bean collections from Southwest Nigeria were evaluated for 16 morphological characters at the Research Farm of the Institute of Agricultural Research and Training, Ibadan, Nigeria in 2006. The purpose of the study was to characterize African yam bean germplasm to identify genotypes with desirable attributes such as seed yield. Data collected were subjected to principal component (PC) and K-means non hierarchical clustering analyses. The collections were significantly different for most of the characters evaluated with the greatest variation in pod and seed yields per plant. The first five PCs explained 70% of the total variation with PC1 and PC2 being responsible for 23 and 17% of the variance respectively. Specific grouping of the collections into five showed that members of clusters 1 and 3 were low yielding. The only member of cluster 2 had the highest seed yield but, it was late flowering. Members of cluster 4 were high yielding and early flowering while the collections in cluster 5 had the highest values for vegetative characters.