Response of tomato (Lycopersicon esculentum Mill.) genotypes to elevated temperature

Abstract

Global warming is an important issue threatening agriculture and allied sectors with serious consequences on food production. Tomato being sensitive to temperature would be influenced by elevated temperatures under climate change scenarios. Physiological response of five tomato genotypes, Arka Vikas, Arka Saurabh, Abhinava, RF4A and 2195 to mild elevated temperatures at peak flowering and peak fruiting stages was evaluated in temperature gradient tunnel (TGT) facility. The increase in temperature above the optimal, caused reductions in net photosynthesis rate, transpiration and stomatal conductance with differences in response among the five genotypes. The reductions were large at peak flowering stage compared to peak fruiting stage. The Photochemical efficiency of PSII was also reduced at both peak flowering and fruiting stages due to increase in temperature. At peak fruiting stage, due to increase in temperature, leaf epicuticular wax content increased across the genotypes and higher total soluble sugars, reducing sugars and proline content contributed to increase in leaf osmotic potential. Overall, better performance of germplasm line 2195 and cv. Arka Vikas was observed under elevated temperature.