Assessment of Genetic Variability of Wild Apple (Malus spps) Genotypes in Kashmir Valley

Abstract

The present investigation was carried out in order to survey, document and characterize available germplasm of wild apple to obtain information on the variability and genetic divergence with respect to various traits. 33 genotypes of wild apple were collected. A significant difference in various fruit and leaf traits was observed although maximum range was observed for fruit weight i.e. 1.06 g in Selection 3 and 81.34 g in selection 20 followed by TSS (6.70°Brix in Selection 10 and 16.30 °Brix in Selection 4). Estimates of divergence among 33 wild apple genotypes revealed that significant divergence existed among them. The genotypes under study were grouped into 8 clusters as per Mahalanobis D2 analysis with maximum number of genotypes in cluster I (17 genotypes) followed by cluster III (8 genotypes), cluster II (3 genotypes) and rest were monogenotypic.  The maximum intra cluster distance was observed in cluster III (139.24) followed by cluster I (67.77) where as the inter cluster distance was maximum between cluster II and V (5213.52) followed by cluster II and IV (4895.20). Cluster means also showed significant differences in terms of various observed traits with maximum range in fruit weight (1.34 g in cluster IV to 79.19 g in cluster II) followed by TSS (6.70 °Brix in cluster IV to 16.30 °Brix in cluster V). The crosses between the genotypes of cluster II with V and II with IV and cluster I with II are likely to exhibit high heterosis and produce recombinants with desired traits in segregating generations. Besides this, principle component analysis (PCA) was performed to study correlation and to interpret relationship among genotypes. Results revealed that PC1 variation observed was 88.19% while from PC2 variation was observed as 8.84%.