Genetic divergence was worked out in the new germplasm of apple (Malus × domestica Borkh.) including 42 genotypes. Mahalanobis's D2 statistics was applied for identifying the potential parents to be involved in the hybridization programme for trait specific improvement or selecting better segregants. On the basis of performance for various traits, genotypes were grouped into three clusters and maximum numbers of genotypes i.e. 28 were accommodated in cluster I , while 10 and 4 genotypes were arranged in cluster II and III respectively. The average intra cluster distance was maximum in cluster II (2.214) and minimum in cluster III (1.212). Inter cluster distance was maximum between cluster II and III (5.077) indicating that hybridization between genotypes from cluster II and III can be utilized for getting the superior recombinants in segregating generations. On the basis of cluster means for various characters , cluster II was found superior for shoot thickness (0.34cm), inter - nodal length (2.38cm), number of lenticels (62.10) and leaf blade length (8.79cm) whereas cluster III was found superior for leaf blade width (5.10cm), petiole length (2.64cm) and leaf blade ratio (3.62). Hence, hybridization between parents from cluster II and cluster III for these characters can produce better recombinants in segregating generations.
Apple, Cluster analysis, D2 statistic, Genetic divergence
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