Genetic diversity of ber (Ziziphus mauritiana L.) cultivars using physico-chemical characteristics
The present experiment was conducted to estimate the physico-chemical diversity of twelve Indian jujube cultivars. A sum of fifteen quantitative characters were explored and subjected to multivariate analyses. Significant variability was observed across the ber cultivars under study. Pearson’s correlation analysis identified days to first flower initiation, a higher number of flowers per cluster and a higher number of retained fruits per cluster which could be used as the basis of selection for identification of high yielding ber cultivars. The principal component analysis (PCA) estimates 60.2% of the total variability in ber cultivars is contributed by PC1 and PC2. The scatter plot of the first two components highlights the number of retained fruits per cluster, yield per tree, pulp weight, fruit width, stone weight and number of flowers per cluster as principal characters that played a significant role in the total variability. Further, PCA also helped to identify Mehrun, Manuki and Chhuhara as superior ber cultivars which performed well with respect to the PC1 and PC2. The Mahalanobis D2 statistics grouped all the twelve ber cultivars into five clusters indicating the existence of ample genetic diversity among the cultivars. Considering the inter-cluster distance along with cluster mean it could be concluded that the cultivars of cluster II and Cluster III may be utilized to estimate the combining ability for effective exploitation of heterosis or to isolate desirable transgressive segregants.