1.使用不育系原种作制种母本。根据国家标准,杂交稻制种田间父母本杂株率一级种应不高于0.1%,故使用纯度达99.9%的不育系原种作母本,制种田可基本不去杂,对于提高种子纯度效果显著,坚决杜绝用不育系纯度低的种子制种。 2.选择适宜的制种时段。改用中山区洋田中稻制种和春马铃薯或春烟后作制种,光温条件好,同时加强田间管理,提高单产,可降低自交或杂株串粉结实在总产中所占的比例,单产越高,纯度也越高。 1. The use of sterile lines as seed breeding mother. According to the national standard, the first parent strain of hybrid rice should not be higher than 0.1% of the primary species. Therefore, if the male sterile line with a purity of 99.9% is used as the female parent, Significant effect of seed purity, and resolutely put an end to sterile seed with low purity seeds. 2. Select the appropriate seed production period. Switch to Yangzhong Zhongtian rice varieties and spring potato or spring tobacco for seed production, light and temperature conditions are good, while strengthening field management, increase yields, can reduce the selfing or stringiness of hybrids in total production accounted for Proportion, the higher the yield, the higher the purity.