Green Global
Foundation   Journal
...an emerging window for scientific research and publication across the globe

GENETIC ANALYSIS FOR HEAT TOLERANCE IN SPRING WHEAT (Pages : 7 - 14)

To assess genetic variability, heritability, and genetic advance in wheat. Twenty wheat genotypes were studied in non-stress (Irrigated timely sowing) and heat stress (Irrigated late sowing) conditions. The analysis of variances showed highly significant variations (P<0.01) among the genotypes for yield, yield contributing, phenological and physiological characters in both optimum and late sowing heat stress conditions. It was observed that there was a pronounced effect of heat stress on the yield of wheat and reduced the grain yield by about 34.49%. Under optimum sowing conditions, the genotypes showed minimum variations (both for GCV and PCV) for most of the phenological, physiological, and yield contributing traits. In late sowing condition, the chlorophyll content of flag leaf at grain filling stage, biomass, grains spike-1, 1000-grain weight, and grain yield showed more than 10% variation and the rest of showed less amount of genotypic and phenotypic variations. Estimates of heritability for different phenological, physiological and yield contributing traits in ITS condition ranged between 43.29 to 99.20%. Similarly, the estimates of heritability for different phenological, physiological and yield contributing traits in ILS condition ranged between 27.27 to 93.22%. The traits heading days, maturity days, canopy temperature at the vegetative stage, canopy temperature at grain filling stage, biomass, plant height, spikes m-2, grains spike-1, and grain yield exhibited high heritability estimates under ILS condition. Under ITS condition, the traits heading days, plant height, spikes m-2, grains spike-1, 1000-grain weight, and grain yield exhibited more than 10% genetic advance in % of mean and the rest exhibited less than 10%. Biomass, grains spike-1 and grain yield had high h2b, high GA in % of mean along with a wide range of genetic variation and lower environmental influence under heat stress condition. Direct phenotypic selection for these traits will be rewardDownload