Evaluation of Genetic Diversity of Wheat (Triticum aestivum) Lines Under Terminal Heat Stress in the Hisar Environment

Abstract

Various environmental stresses affect plant development and growth globally and restrict agricultural output and productivity. Wheat plants are negatively impacted by terminal heat stress, which lowers productivity. The correlation between grain yield and other qualities may determine the plant material's ability to minimize the effects of heat stress on yield, and a trait variance aids in the identification of attractive genotypes in a breeding program. To accomplish this, the genetic variability, heritability, correlation and path coefficient analyses of 64 bread wheat genotypes were conducted. As a result, all 15 morpho-physiological traits revealed highly significant genotypic variations. Total chlorophyll content and main spike weight were both higher than 42% and 16%, respectively, for the genotypic coefficient of variation and the phenotypic coefficient of variation. The grain yield per plot indicated a significant and positive correlation with spike length, spike weight, number of grains per spike, number of spikelets per spike, 1000-grain weight, biological yield per plot, grain growth rate, total chlorophyll content and number of productive tillers per meter. As a result, five genotypes, P13833, P13828, P13031, P13723, and P13726, had higher yields and should be utilized as parents in breeding programs. The results revealed that the selection of key physiological and morphological characteristics associated with grain production significantly raises wheat productivity in situations like heat stress.