STUDY ON THE HEAT TOLERANCE IN TOMATO (LYCOPERSICONE SCULENTUM MILL.) AT HYDERABAD, SINDH

Present study was conducted to analyse the heat tolerance and correlation estiamtes in Tomato (lycopersicon esculentum Mill.) at Hyderabad, Sindh. The data was collected for membrane thermostability, elongation of stigma and antheridial cone spiliting, flowers no. and number of flowers shed per plant and production per plant was under the study. The data revealed significant differences among the studied traits. Among the genotypes, (1) Fanto F1 Hybrid exhibited the highest heat tolerance, followed by was (2) Hybrid tomato HT-101B, as evidenced by their high membrane thermostability and low number of flowers shed. These genotypes also demonstrated the highest fruit yield during the hot period. The analysis showed a positive association between fruit yield and membrane thermostability, while a negative association was observed with the number of flowers shed, stigma tube elongation, and antheridial cone splitting. In summary, Roma, with the lowest membrane thermostability, was found to be the most sensitive genotype to heat stress.