Effect of High and Low Temperatures on Pollen Germination and Seed Set in Snap Beans

Abstract

Pollen germination in vivo in beans ( Phaseolus vulgaris L.) was less at 8° and 12°C than at 18°. There were large cultivar differences, and germination at 9 am was no different from that at 3 pm . Pollen from bean flowers grown in the greenhouse at 21° Day/18°C Night (D/N) was transferred to plants in bloom at combinations of 8°, 10°, and 12° N, and 20°, 25°, and 30° D. Pollen from plants at the 9 temperature combinations also was used to pollinate plants in the greenhouse. Pollen from plants grown at 30° as compared to 20° and 25°, resulted in reduced seed yields. Conversely, viable pollen transferred to plants at 30° reduced set insignificantly. Thirty/8° D/N combinations resulted in the lowest yields. Low night temperatures appeared to inhibit ovule viability. In contrast, high temperatures reduced pollen viability. NY 5-161 and OSU 1604 were more stable than BBL 47, BBL 92, and PI 165426 at both high and low temperatures.