关键词: 冬小麦, 冬小麦, ‘衡科6021’, 播期, 种植密度, 双晚技术, 产量, 产量构成因素

Abstract: To explore the correlation between the grain proportion and yield and quality traits of hybrid rice, using the high-yield and high-quality variety‘Tianyouhuazhan’as the control, the combinations were obtained from the hybridization with seven three-line sterile lines and five self-selected restorer lines. The panicle number per plant, the total number of grains per panicle, grain volume, proportion, 1000-grain weight, plumpness, head rice rate and chalkiness degree were detected. There were differences in the panicle number per plant, the total number of grains per panicle and chalkiness among different combinations. The grain proportion increased with the increasing grain weight and volume, and it was positively correlated with yield, but negatively correlated with head rice rate. Through the correlation analysis between grain proportion and yield quality traits, it was found that the grain proportion was positively correlated with head rice rate (0.8370**) and 1000- grain weight (0.7643**), and the correlation coefficients reached extremely significant level, among which 1000- grain weight was the biggest factor affecting yield and the important factor determining the grain proportion. Grain proportion was also positively correlated with the total number of grains per panicle (0.2697) and volume (0.0053), and negatively correlated with plumpness (- 0.2065), the panicle number per plant (-0.3326) and chalkiness degree (-0.1546). The increase of grain proportion can improve head rice rate and reduce the degree of chalkiness, thus to improve the yield and quality of rice. In the breeding of hybrid rice, the panicle number per plant and the plumpness should be considered in the case of large grain, and unilaterally increasing the grain weight would result in head rice rate decreasing. Therefore, in order to balance the yield and quality, the grain proportion should be moderate.