Impact of temperature on phenology and pollen sterility of wheat varieties

Low temperature during reproductive stage of spring wheat causes sterility of pollen grains and reduced yield. Field experiment was conducted during the winter season in the farm of Indian Agricultural Research Institute with wheat crop to study the effect of temperature on phenology and pollen sterility of spring wheat crop. Lower mean temperature during the crop growth period led to enhanced the crop growth period in both aestivum and durum varieties of wheat crop. Results showed that in early sowing treatment pollen sterility percentage was very high (46.1%) in HD 2851 variety. This in turn led to decreased pollen germination and lesser yield in wheat crop. Pollen germination was maximum between mean temperatures of 18-20C, while at lower temperatures germination of pollen grains got reduced in all wheat varieties. A good positive correlation was obtained between pollen germination percentage and yield (R=0.65) of wheat crop. Data from this experiment indicate that low temperature during reproductive phase could limit wheat yield by affecting its phenology and fertility of pollen grains. Adaptation measures need to be developed for reducing yield loss of wheat in areas experiencing very low temperature during anthesis stage.