Inter-relationships in Morphotypes of Greater Yam (Dioscorea alala L.)

The germplasm holding in greater yam (Dioscorea alata L.)consisting of 182 accessions belonging to 19 morphotypes collected from different agro-ecological situations of peninsular India were subjected to a detailed investigation on characterization of both above ground and below ground vegetative parts with respect to 49 qualitative and 22 quantitative traits. Seventy-six descriptor states were analyzed for pair-wise similarity coefticients by un-weighted pair-group method analysis (UPGMA) and also for single and complete linkage. The study revealed existence of 9 major arbitrary clusters indicating close resemblances between many of the morphotypes. Clustering pattern did not show any strict relationship between geographical distribution and morphotypes as the accessions from different geographic regions and ofdifferent morphotypes were grouped in most ofthe clusters. Based on these observations, an attempt is being made here tointerprettheextent ofsimilarity within andbetweenthe earlierdescribed morphotypes.