Physiological studies in wheat genotypes under heat stress

The present investigation was conducted to evaluate various physiological traits & identify promising wheat genotypes under terminal high-temperature conditions. The twenty genotypes i.e. tolerant (WH 730 WH 1124 WH 1021 HD 3059 DBW 90 PBW 373 Raj 3765 HD 2851 HD 2285 PBW 550) & ten heat susceptible (HD 2967 DPW 621 WH 1105 DBW 88 HD 3086 HD 2733 WH711 WH 1080 WH 1142 & K 0307) were grown during rabi season of 2016 - 17 at Field CropResearch Area of Wheat & Barley Section Department of Genetics & Plant Breeding CCS HAU Hisar The experiment was laid out in factorial RBD consisting of 4 rows of 3m length with a 20×5 cm spacing within rows & between plants respectively. Terminal high temperature significantly influenced physiological biochemical yield & yield attributes in both heat susceptible & heat tolerant genotypes but the reduction was more pronounced in the susceptible genotypes in comparison to the tolerant ones. WH 1021 was adjudged to be the most tolerant genotype due to minimum reduction in photosynthetic rate transpiration rate chlorophyll content & minimum increase in canopy temperature cell membrane stability.