Drought and heat stress mitigation in rice for yield improvement using temperature induction response technique

The investigation was conducted in two experiments in the College of Agriculture Vellayani, Kerala Agricultural University. First experiment was done to standardize the Temperature Induction Response (TIR) protocol for rice. Second experiment was conducted to study the effect of TIR technique on yield and yield attributes under drought, heat and combined drought and heat stress; 52°C for 3 h was selected as lethal temperature and 32–42°C for 5h & 42–52°C for 30 min were selected as induction temperatures. Results revealed that TIR induction had significant effect on yield and yield attributes under combined drought and heat stress. TIR induced plants without any stress showed the highest growth and yield attributes. Performance of rice genotypes Nagina-22 and Apo improved under combined stress condition using TIR induced seedlings. Apart from these two genotypes, Ptb-15 and Ptb-7 recorded better performance under heat stress and drought, respectively. For combined stress, Ptb-30 and Ptb-15 showed better performance compared to other genotypes. Ptb39 was identified as the most susceptible genotype for both drought and heat stress conditions, but TIR induced plants of susceptible genotype showed improved stress tolerance. Hence, this technique can be used as a potential tool for improving the performance of high yielding abiotic stress susceptible genotypes under stress conditions.