2017 ASHS Annual Conference

The United States is one of the world’s leading producers of tomatoes. Tennessee ranks among the top six as one of the major fresh market tomato producing states in the nation. Extreme heat conditions have an adverse effect on pollen development, and thus cause significant reduction in tomato production. The objective of the project was to study the effects of temperature on pollen, seeds and fruit development in vivo. Tomato ‘Micro-Tom plants were grown in incubators under 14/10 hour photoperiod under three temperature regimes: 32⁰C continuously, 26⁰C continuously, 32/26⁰C day/night. After 2 months of treatment, pollen count, fruits set, fruit size and seed development data were collected. No pollen developed when plants were grown under continuous 32℃ condition and there was no fruit set. Under 32/26 ℃ conditions, tomato plants produced viable pollens but most of them did not germinate at 26 ℃. Under 26 ℃ treatment, tomato plants produced abundant viable pollens which germinated at 26 ℃ and some also germinated at 32 ℃ under in vitro condition. Studies indicate that heat stress during flower development has a detrimental effect on pollen fertility and tomato fruit sets as well as development.