The Asiatic Dioscorea alata yam species is an important food crop, especially in Cote d'lvoire. It has high yield and stores longer than Dioscorea cayenensis/rotundata yam and therefore fills the hunger gap created w...The Asiatic Dioscorea alata yam species is an important food crop, especially in Cote d'lvoire. It has high yield and stores longer than Dioscorea cayenensis/rotundata yam and therefore fills the hunger gap created when other yam types arc not available. However, very little research has been done on it. Several cultivars are susceptible to pests and diseases and lack the aesthetic values of smooth skin and elegant tuber shape ofDioscorea rotundata that appeal to consumers in the market. This study therefore sought to establish the genetic variability and relationships among 35 accessions of Ghanaian Dioscorea alata together with 14 accessions introduced from International Institute of Tropical Agriculture in Nigeria. Morphological variation was studied to establish genetic relationship among 49 accessions assembled as Dioscorea alata in Ghana. Principal component analysis (PCA) indicated that the first two principal components accounted for 25.27% of total variation from accessions with PCA1 and PCA2, contributing 13.92% and 11.35%, respectively. Cluster analysis performed clearly separated the 49 accessions into three main groupings using unweighted neighbour-joining method. Morphological descriptors were able to group the accessions into distinct clusters independent of place of collection.展开更多
文摘The Asiatic Dioscorea alata yam species is an important food crop, especially in Cote d'lvoire. It has high yield and stores longer than Dioscorea cayenensis/rotundata yam and therefore fills the hunger gap created when other yam types arc not available. However, very little research has been done on it. Several cultivars are susceptible to pests and diseases and lack the aesthetic values of smooth skin and elegant tuber shape ofDioscorea rotundata that appeal to consumers in the market. This study therefore sought to establish the genetic variability and relationships among 35 accessions of Ghanaian Dioscorea alata together with 14 accessions introduced from International Institute of Tropical Agriculture in Nigeria. Morphological variation was studied to establish genetic relationship among 49 accessions assembled as Dioscorea alata in Ghana. Principal component analysis (PCA) indicated that the first two principal components accounted for 25.27% of total variation from accessions with PCA1 and PCA2, contributing 13.92% and 11.35%, respectively. Cluster analysis performed clearly separated the 49 accessions into three main groupings using unweighted neighbour-joining method. Morphological descriptors were able to group the accessions into distinct clusters independent of place of collection.