Morphological Characterization of Greater Yam (Dioscorea alata L.) Landraces in Kerala

Yams belonging to Dioscoreaceae family are important climate resilient food security crops widely cultivated in India and Africa. In India, one of the major cultivated yam species is greater yam (Dioscorea alata L.). It provides a good source of dietary carbohydrates in tropical and subtropical regions. In the present study, 45 accessions conserved in the National repository of tuber crops germplasm at ICAR-CTCRI were characterized based on 25 qualitative and 13 quantitative traits including the major yield components and four biochemical characteristics. Traits like tuber shape, tuber flesh colour, tuber skin texture, tuber cortex colour, leaf shape and young leaf colour were all found to be of great importance in distinguishing the accessions. These traits were considered for Principal Component Analysis (PCA) with a measure of Sample Adequacy greater than 0.5. The first six principal components of data accounted for 50.12% of the total variance among accessions. The cluster dendrogram based on morphological data revealed that the D. alata accessions exhibited greater degree of genetic variation for the 42 different morphological traits observed. According to the morphological data, there were no duplicate accessions and Da 331, Da 390 and Da 340 were found be the highly divergent among the accessions studied.