High temperature induced antioxidative defense mechanism in seedlings of contrasting wheat genotypes

Leaf discs of 15 d old seedling of wheat genotypes C-306 (temperature tolerant) and HD 2329 (widely adapted) were incubated at 25, 35 and 45ºC to analyse the extent of membrane injury and antioxidative defense mechanisms. It is suggested that the tolerant genotype C-306 exhibited lower accumulation of MDA and H₂O₂ content owing to increased activities of superoxide dismutase, peroxidase and catalase under high temperature conditions. The higher water retension capacity and lower membrane injury in C-306 further helped it in imparting high temperature tolerance. The HD 2329 was also able to resist high temperature stress to some extent via above adjustments.