Effect of spring low temperature on ear development and grain weight of winter wheat

According to natural low temperature from April 12 to April 14 in 2010,36 wheat varieties utilized in the production of Henan Province were selected to study the effect of spring low temperature on ear development and grain weight of wheat. The results showed that spring low temperature affected greatly the spikelet development and grain weight. Comparing severe hazard with light hazard,the total spikelets per ear decreased percentage by 0. 98,sterile spikelets per ear increased by 3. 32,the ratio of sterility increased by 17. 68% ,basal floret number decreased by 8. 42% ,the seed set rate decreased by 5. 90% ,kernel number per ear decreased by 16. 01% ,and 1 000-grain weight decreased by 2. 55 g. All the differences were very significant,and the influence degrees varied with the different varieties. The correlations between most differences of ear traits were significant.