Abstract: Using Matlab process, the grain filling process of hybrid wheat 901 and its parents was fitted by Richards equation on computer in order to study the characteristics of grain filling in hybrid wheat 901. The active grain growth period of hybrid wheat 901 was 6 days longer than that of Shan 229, its final grain weight (43.7 g?1000-grain-1) was higher than that of Shan 229 (36.3 g?1000-grain-1). N values of 901 and R205 were both less than 1, their grain growth was fast in the early filling stage, slower in the middle-late stage. N value of Shan 229 was > 1, its growth was slow in the early stage and fast in the middle stage. The duration of early stage of 901 was short and the duration of middle-late stage of 901 was longer. The situation of Shan 229 was totally reversed. In parents, the father plant R205 was similar with hybrid wheat 901, its mother plant K3314A was similar with Shan 229. It was also found that Richards equation was more suitable for fitting the grain filling process of wheat than Logistic equation.

Key words: Hybrid wheat, Parent plants, Grain-filling