杂交稻大面积推广以来,“三系”亲本由于生物学混杂、机械混杂和自身的遗传变异,已发生不同程度的分离、混杂和退化,影响了杂种优势的发挥,阻碍了杂交水稻的发展。因此,开展提纯复壮工作,提高“三系”和杂交种的纯度,是当前杂交稻推广工作中一项急待解决的问题,已引起各地的普遍重视,并做了大量工作。我们从一九七七年起,对生产上推广的几个主要亲本,开始了提纯复壮工作。现根据几年的 Since the large-scale popularization of hybrid rice, the “three-line” parents have separated, mixed and degenerated to some extent because of the biological hybrids, mechanical hybrids and their own genetic variations, affecting the development of heterosis and impeding the development of hybrid rice. Therefore, carrying out the work of purifying and rejuvenating and improving the purity of the “three lines” and hybrids is an urgent issue in the popularization of hybrid rice. It has drawn universal attention and done a great deal of work. Since 1977, we started the process of purifying and rejuvenating several major parents in production promotion. Now based on a few years