Genetic Variation and Selection Criteria for Seedling Traits in Rice Under Low Temperature Stress

Standard deviation and Genetic variability studies were conducted for ten seedling vigour traits among 37 cold tolerant rice genotypes. Standard deviations vary among the genotypes and characters. Traits root, shoot and seedling length, seedling vigour index, coleoptiles length, REDCOL, coleoptiles length>5mm and PERCOL most of the genotypes recorded less than 10 standard deviation under different temperatures. The estimates of phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) all most same for the traits root length, shoot length, seedling vigour at normal and different temperatures indicating minimum environmental influence and consequent greater role of genetic factors on the expression of traits. Root and shoot length, seedling growth, seed vigour and REDCOL recorded high GCV, PCV, heritability, genetic advance % of mean, suggesting that these characters are controlled by adding gene action and can be transmitted to the progeny through phenotype based selection. Genotypes Himalaya, Vivek dhan-82, VL Dhan-206, VL Dhan-206 and Jhelum identified based on the traits having higher estimates of heritable genetic parameters and lesser standard deviation for the utilization in the crossing programme for the development genotypes with tolerance to cold in rice.