Abstract:

‘Yuanfeng A’ is an Indica CMS line, with resistance to blast, high quality and strong heterosis. Twenty six hybridized combinations of ‘Yuanfeng A’ were planted as middle-season rice and late rice, respectively. In this study, the qualitative differences of these hybridized rice combinations, which contained rice milling quality, appearance quality and food quality, were discussed in different planting season conditions. The results suggested that comparing with middle-season rice, the late rice of ‘Yuanfeng A’ combinations had three advantages in grain quality. First, the brown rice rate, polished rice rate, head rice rate were found to increase 2.2%, 3.5% and 14.8%, respectively in aspect of milling quality. Second, the chalk rice rate and chalkiness degree were decreased 56.1% and 69.5%, respectively. Third, the gelatinization temperature of food quality was found to increase 13.6% on average. While the highest increasing was 34.1%, the lowest was 1.6%. At the same time, there was a trend that the lower content of amylose of combinations was increased, and the higher were decreased. Therefore, ‘Yuanfeng A’ was believed to be easy for breeding high quality hybrid rice which chalkiness degree was within 5% and reached grade 3 of National Standard, using arrange the optimum sowing time to avoid the high temperatures during the filling stage.