应用细胞质雄性不育系构建甘蓝型油菜三交杂种

在测交一代保持不育系不育特性的品种（系）称为临时保持系；将回交３－４代仍能保持不育系不育特性的品种（系）为永久保持系．前者较多，后者较少。临时保持系的研究和三交杂种的应用结果表明；三交杂种方法是克服细胞质雄性不育系微量花粉的有效途径．两个强优势的三交杂种的产量比中油８２１增产１２％以上，一个比相应的单交杂种增产２．２％，一些三交杂种的抗性得到改良。

ESTABLISHMENT OF THREE-WAY CROSSES HYBRID BY USING CMS IN WINTER RAPESEED (BRASSICA NAPUS L)

The maintainers that were maintainable in the third, fourth backcrossing were called permanent maintainers, and the maintainers that were maintainable only in the first testcrossing were called temporary maintainers. There were plenty of temporary maintainers and few permanent maintainers in rapeseed. How to utilize those temporary maintainers was studied. The results indicated that it was possible to develop three-way crosses hybrids with high vigor by employing the method of three-way crosses,in which the plenty of temporary maintainers were utilized. The seed yield of some three-way crosses hybrids (9886,9566)was 12% higher than commercial variety (Zhonsyou 821 )and three -way crosses hybrid (9886 ) was 2.2% higher than its single cross hybrid (7826). The disease resistance (tolerance ) of some three way crosses hybrids was better than one of their single cross hybrids.