Abstract

                                Extent and magnitude of genetic divergence for seven characters among thirty-three genotypes of grain amaranth (Amaranthus hypochondriacus L.) were determined for the purpose of identifying more diverse parents, which are expected to create maximum variability. The highest genetic contribution towards diversity was made by number of branches (21.9697). Contribution of canonical roots in per cent in first four vectors was 46.611, 24.320, 12.077, 6.771 and total 89.779, respectively. Based on genetic divergence D2 statistics, genotypes were grouped into 16 clusters in which cluster I (BGA 9, BGA 20, BGA 14 and BGA 11) and cluster XI (RMA 42, RMA 43, BGA 4 and SKNA 809) contained maximum number of four genotypes, Cluster II, III, IV, V, VIII, IX, XIII, XIV and XVI (2 in each case), 3 genotypes in cluster VII (RMA 45, BGA 21 and IC 35482) and Cluster VI (SKNA 403), X (Suvarna), XII (SKNA 401) and XV (GA 2) have one genotypes. The clustering pattern revealed that there was no relationship between genetic divergence and eco-geographical region. Intra cluster values ranged from 0.00 to 23.196 and cluster XIII was the most diverse group. The inter cluster values ranged from 20.3 to 26809. Maximum divergence was noticed between clusters III (AmbikaGA12-1 and KBJ3) and XII (SKNA401) (26809) followed by clusters X (Suvarna) and XVI (AmbikaGA12-2 and BGA 2) (20017) and clusters III (AmbikaGA12-1 and KBJ3) and X (Suvarna) (15031). The diverse clusters derived could be used in hybridization programmes to generate wide range of transgressive segregants to develop high yielding grain amaranth varieties.

Key words : Amaranthus hypochondriacus, D2 statistics, Genetic diversity, Canonical roots.