Author(s):

Sabesan T

Abstract: Genetic divergence is an efficient tool for the selection of parents used in hybridization programme. The present investigation was carried out to evaluate genetic diversity for flash flood tolerance of twenty six rice genotypes. To study the field performance of the rice genotypes under natural flash flood, the experiments were conducted at two places viz., a low lying field to screen the genotypes for flash flood tolerance (E2) and an elevated field (E1) representing normal condition which served as irrigated control. Pooled analysis was also carried out. The observations on eleven characters viz., days to 50 per cent flowering, plant height, number of tillers per plant, number of productive tillers per plant, panicle length, number of grains per panicle, 1000 grain weight, grain length, grain breadth, grain L/B ratio and grain yield per plant were studied. Genetic divergence based on Mahalanobis D2 statistic grouped the rice genotypes into seven different clusters in E1 and six clusters in both E2 and pooled analysis. The maximum intracluster distance was observed by cluster IV in E1, E2 and pooled analysis. The maximum intercluster distance was observed between clusters IV, V, VI and VII. The six rice genotypes namely, JGL- 384, TN- 1, MTU- 1010, NDLR- 8 and Swarna Sub 1 from these clusters could be used to obtain superior progenies and hybrids for flash flood tolerance. The characters namely grain yield per plant along with grain length were the two major contributors in E1. In the flash flood environment E2, the traits grain yield, 1000 grain weight and number of grains per panicle were the major contributors. In pooled analysis, 1000 grain weight and number of grains per panicle remained as major contributors towards divergence. Therefore, these characters may be given importance during hybridization programme

Pages: 2210-2214  |  1130 Views  209 Downloads

Download (569KB)