Genetic variability and traits association in wheat under terminal heat stress in the Haryana environment

Abstract

Numbers of environmental stresses influence plant growth and development, which limits agricultural production and productivity, globally. High heat stress is a major factor that significantly reduced the wheat grain yield. Terminal heat stress adversely affects wheat plants resulting in low productivity. The ability of the plant material to mitigate the heat stress on yield may depend on the association between yield and other traits, and the variability of a trait will help identify desirable genotypes in a breeding program. For this purpose, sixty-four bread wheat genotypes were evaluated to assess genetic variability, heritability, correlations and path coefficient analysis of the traits. As result, highly significant differences in genotypes for all 15 morpho-physiological traits were observed. GCV and PCV exceeded 42% for total chlorophyll content and 16% for Main spike weight. Grain yield/plot was significantly and positively associated with spike length, spike weight, number of grains/spike, number of spikelets/spike, 1000-grain weight, biological yield/plot, GGR, total chlorophyll content and number of productive tillers/meter. As conclusion, the production of wheat in heat-stressed environment is greatly enhanced by the selection of key morphological and physiological features associated with grain yield. Five genotypes, P13833, P13828, P13031, P13723, and P13726, had high yields under heat stress condition and ought to be utilized as parents in breeding programs.