Screening of tomato genotypes underhigh temperature stress for reproductive traits Singh Umesh, Patel Pradeep Kumar, Singh Amit Kumar, Tiwari Vivek, Kumar Rajesh, Rai N, Bahadur Anant, Tiwari Shailesh K, Singh Major, Singh B Division of Crop Improvement, ICAR-Indian Institute of Vegetable Research, PB-01, PO-Jakhini (Shahanshahpur), Varanasi-221305, (U.P.), India Online published on 8 July, 2016. Abstract Twenty-one tomato lines were evaluated under summer season in the field condition, the average day and night temperature were 38.4 and 19.7°C, respectively. Several floral and fruit traits were adversely affected due to chronic high temperature stress which clearly indicated specific physiological processes of flower development were especiallysensitive tohigh temperaturestress. Flower drop are highly associated with styler exertion rate percentage. A significantincreasein flower drop(19.30%to74.36%), styler exertion (20.37% to 83.72%) and significantly decrease in pollen viability (14.78–74.55%) and fruit set truss−1 (15.45 to 75.37) were noted among the genotypes. On the basis of initial screening with respect to fruit set at high temperature stress, three lines i.e. CLN-2026, EC-538439 and EC-538148 emerged as high temperature tolerant genotypes. These lines, along with highly susceptible varieties i.e. Arka vikas, were critically observed for the stress tolerance traits. Most of the genotypes showed stigma exertion or tip burn under high temperature condition. Fruit number and fruit weight were the important yield components, which were severely affected under high temperature stress and ultimately yield was markedly reduced. Yield potential of the genotypes which was dependent on fruit set and fruit weight severely reduced under high temperature stress and yield varied from 386 g plant−1 (EC-538380) to 1832 g plant−1 (CLN-2026) in summer. On the basis of initial selection, it was concluded that the traits like fruit setting, pollen and yield attributes traits could be used in selection of high temperature tolerant genotypes for better fruit setting and tomato genotypes, i.e. CLN-2026 can be used as a source of high temperature tolerance genes for further breeding programs. Top Keywords High temperature, floral traits, screening, yield attributes traits, pollen traits, stigma exertion. Top |