Study on Physiological and Grain Filling Property of Different Senescence-types of Wheat Cultivars under Drought Stress at Filling Stage

With 11 winter wheat cultivars as the materials and the time of chlorophyll degraded to 0 under drought stress in field at filling stage as the standard,11 varieties were divided into different senescence-types.The changes of main agronomic characters and physiological indexes of different senescence-type wheat were compared,the process of wheat grain filling was fitted with logistic equation and the relationship of filling parameter and wheat grain weight and the filling law of wheat were analyzed.The results showed that the time of chlorophyll content and available leaf area degraded to 0 of anti-senescence wheat were delayed 7-15 d than those of senescence wheat under drought stress,while the 1000-grain weight of anti-senescence wheat was less 10 g than that of senescence wheat.Under drought stress,the grain filling rate had significant effect on grain weight,but grain filling duration had no significant correlation with grain weight.