Physiological and biochemical traits contributing for high temperature tolerance in tomato (Solanum lycopersicum L.) Amrutha V, Beena R*, Shanija S Department of Plant Physiology, College of Agriculture, Vellayani, Kerala Agricultural University, Thiruvananthapuram-695522, Kerala *Corresponding author: beenaajithkumar@gmail.com
Online published on 28 September, 2023. Abstract A study was undertaken to evaluate the physiological and biochemical parameters and to quantify yield of twenty-two contrasting tomato genotypes when exposed to high temperature stress. Experiment was conducted in the Department of Plant Physiology, College of Agriculture, Vellayani during two growing seasons i.e., September to December, 2019 and March to June, 2020. The experiment was laid out in completely randomized design with two treatment levels i.e. control and high temperature stress (36+/-2°C) with three replications each under first season and 38+/-2°C during the second season. The high temperature stress was induced from flower initiation to maturity stage by keeping the pots in a temperature controlled green house facility for 45 days. The presence of stigma exertion, reduction in chlorophyll content and photosynthetic rate, reduced starch content and soluble sugar content, reduced chlorophyll fluorescence, low leaf membrane thermostabilty (LMT) were the major limitations for reproductive success and good yield. The correlation and regression analysis showed that yield under control conditions had strong positive correlation between LMT, pollen viability, photosynthetic rate, chlorophyll fluorescence, starch, soluble sugar and chlorophyll content. A negative correlation was observed between yield and stomatal conductance and transpiration rate. Under high temperature stress condition, all the parameters showed a positive correlation with yield. Based on the performances of various tomato genotypes under control and heat stress conditions, we were able to identify traits that could be manipulated to improve the high temperature tolerance in tomato. Top Keywords Correlation, High temperature, Physiological traits, Tomato, Yield. Top |