Genetic Variation for Tolerance to High Temperatures in Tomato Using Critical Sterility Temperature

Tomato (Solanum lycopersicum L.) reproduction is influenced by temperature, prominently impacting yield. The ideal daytime range is between 25°C and 30°C and the nighttime temperature is around 20°C for tomato and deviations of a few degrees from these temperatures can have negative effects. The study assessed the effect of temperature on tomato pollen germination and aimed to ascertain the critical sterility temperature for pollen germination. In an open field, pollen from 10 genotypes (Anagha, Manuprabha, Vellayani Vijay, Akshaya, Nandi, IIHR26372, Pusa Rohini, Arka Saurabh, Arka Rakshak, and Arka Vikas) underwent In-vitro temperature exposure ranging from 32 to 40°C at 2°C intervals. Variations in In-vitro pollen germination percentage were observed across the genotypes, notably revealing a sharp decline after 36°C. This decline indicated a pivotal shift in pollen germination and viability. Genotypes, Anagha and Arka Saurabh, were identified as temperature tolerant and susceptible, respectively. The findings present an opportunity to incorporate temperature-dependent pollen response functions and identified genotypes into tomato breeding programs, offering significant implications for enhancing yield under varying temperature conditions.