Upregulation of Superoxide Dismutase and Catalase along with Proline Accumulation Mediates Heat Tolerance in Lentil (Lens culinaris Medik.) Genotypes during Reproductive Stage

Heat stress during reproductive stage of lentil leads to array of physiological and morphological changes affecting lentil production. The effect of high temperature stress (30°-35°) was studied on thirty three lentil genotypes during winter (rabi) trial 2013–2014. Six genotypes comprising three tolerant (LL1372, LL1361, LL1396) and three sensitive (EC78390, LL1380, LL1390) were selected which further raised under timely sown (TS) and late sown (LS) conditions during winter (rabi) trial 2014–15 for biochemical analysis. The higher accumulation of proline content along with higher activities of superoxide dismutase (SOD) and catalase (CAT) was observed in late sown tolerant genotypes, might be helping in reducing oxidative stress caused by reactivite oxygen species (ROS). The higher accumulation of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) content was found in sensitive genotypes might be responsible for membrane damage. The positive and significant correlation was observed in CAT, SOD, and proline whereas these three biochemical parameters showed negative correlation with MDA and hydrogen peroxide content.