Evaluation of genetic diversity for yield and quality parameters of different potato (Solanum tuberosum L.) germplasm

An investigation was carried out at Vegetable Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar during spring-summer season 2011 and 2012 to study the genetic diversity using Mahalanobis’s D2 – technique among thirty five potato (Solanum tuberosum L.) germplasm for important yield attributing and quality traits. The D2 values were calculated and thirty five potato genotypes were grouped into nine clusters for growth characters and ten clusters for quality traits respectively. All the genotypes included in the present investigation, were indigenous, but their grouping in different clusters, suggested that genotypes did not follow the geographic distribution. The cluster I contained the maximum number of genotypes with respect to both yield attributing and quality traits. The inter cluster distance in most of the cases were higher than the intra-cluster distance indicating wider genetic diversity among the genotypes of different groups. Average tuber weight of potato plant contributed maximum (31.76%), followed by number of tuber per plant (27.56%), internodal length (14.45%) and plant dry matter content (13.61%) for growth characters. For quality characters, ascorbic acid content (24.70%), protein content of tuber (20.84%) and TSS of tuber (20.00%) contributed effectively towards genetic divergence. So, these traits will offer a good scope for improvement of yield and quality through rational selection of parental genotypes for future potato breeding. The findings indicated that use of parents selected from the same cross or from a cross involving a common parent should be avoided in hybridization. The results broadly showed there was no parallelism between geographical and genetic divergence.