Huaimai 25,a semi-winter wheat cultivar,was used to study the effect of different plant growth regulators on the grain filling characteristics and grain weight in wheat.The grain filling process of wheat with different plant growth regulators treatments was fitted by Logistic equation in order to explain the changes of grain dry matter,grain filling rate and grain weight.The correlations between grain filling parameters and grain weight in wheat were discussed by correlation analysis.The results showed that...