PHENOTYPIC STABILITY FOR REPRODUCTIVE STAGE COLD TOLERANCE IN RICE

Abstract

Stability parameters in respect of fertility representing reproductive stage cold tolerance were studied using 21 parents and their 90 Fl hybrids at three cold stressed locations. Pooled analysis of variance revealed high genotype-environment interaction for fertility with importance of both the linear as well as nonlinear components. Twenty seven genotypes had significantly greater fertility than the population mean. Three indica and 5 japonica females, and six indica X indica hybrids constituted the top ranking group. Forty nine genotypeshad bi less than 1 and 45 bi greater than l. S-2d was greater than 0 for 66 genotypes. Indica parent K39-96, japonica parent Suweon 235, and 5 indica x indica hybrids (Suweon 287 x IR-15889, K39-96 x IR-7167, Shoa-Nan-Tsan X IR-7167, Suweon 287 X IR-9202 and Shoa- Nan-Tsan X IR-9202) had high fertility, were most stable, and could be considered as ideal genotypes for cultivation under cold environments.