The Effect of High Temperature on the Reproductive Success of Trianthema portulacastrum

Plant reproduction is highly sensitive to rising temperatures, which can lead to pollen abortion, and lower yield in many crop species. It remains uncertain whether wild plant species adapted to hot climates are able to reproduce at high temperature. I studied heat sterility thresholds in Trianthema portulacastrum, a weedy species found throughout the tropics and subtropics, often on barren soils where temperature exceeds 40°C. Plants were grown at seven day/night temperatures: 30/24°C, 33/24°C, 36/24°C, 40/24°C, 44/24°C, 24/40°C, and 40/40°C. Pollen viability significantly declined with increasing temperature, but this did not significantly affect percent pollen germination or seed set. In contrast, seed set was significantly reduced under high night temperature. The results show high night temperatures have a greater impact on reproduction than day temperature, indicating T. portulacastrum is using a night escape strategy to maintain reproductive success in its natural habitat.M.Sc