Abstract: Based on the field experimental data of winter wheat in 2017/2018, grain filling process was analyzed by logistic equation for 2 weak springiness varieties and 6 semi-winter varieties. Correlations on grain weight and grain filling characters were analyzed. The results showed that grain filling rate of semi-winter variety was generally larger than that of weak springiness variety. The 1000-grain weight was significantly increased by the higher grain filling rate at middle and late grain filling stage. The weak springiness varieties grow faster after reviving, bloomed earlier, and lasted longer in grain filling stage. However, the mean and maximum grain filling rates of weak springiness variety were significantly smaller than those of semi-winter variety. The 1000-grain weight was greatly influenced by grain filling rate, especially at middle and late grain filling stages. Although the grain filling duration of different genotype varieties was different, it had little effect on the increase of 1000-grain weight. According to the correlation analysis between grain filling parameters and 1000-grain weight, grain filling rate at quick-increase filling stage and slight-increase filling stage played the key roles. No significant correlation between grain filling duration at all stages and 1000-grain weight were found. It was concluded that the semi-winter varieties of S355, YJ5, and CM1 were more suitable for popularization in the experimental area.

Key words: Winter wheat, Genotype, Logistic equation, Grain filling rate, Grain filling duration