水稻恢复系选育的轮回选择法及其应用效果研究

Method and Application Effect of Recurrent Selection for Restoring Line Bree ding of Rice

利用野败型细胞质雄性不育性作为遗传工具 ,进行水稻恢复系的轮回选择。试验证明 :(1)由于构建基础群体时加入了一定比例具有保持系性质的常规品种 ,以及在后续世代中不断将经过后裔测验 ,证实在主要恢复基因位点上均为杂合型的中选可育株种子返回群体 ,给不育株授粉 ,因而保证了每轮次轮回选择群体内不育株比例基本稳定在 1 4左右 ,有足够数量的不育株可供进行表型选择和构建下一轮次的轮回选择群体 ,使轮回选择可以代代进行。 (2 )经过 1～ 2个轮次的轮回选择 ,群体内绝大多数植株的出穗期和株高已经符合育种目标要求 ,这为群体经济性状和品质性状的选择提供了前提条件。 (3)在改良群体的同时 ,从轮选群体中不断选择可育单株进入选种圃 ,培育了一些优良恢复系纯系 ,配制出优良杂交组合 ,其中以优良恢复系P0 0 4与粤丰A配制的杂交组合 30 37较为突出 ,该组合已进入江苏省水稻中间试验。

Cytoplasmic male sterility of wild abortion (cms WA) was used as a genetic tool in rice recurrent selection of restoring lines breeding. The results showed that: (1) The number of sterile plants in the population could be stabilized at ratio of about 25% in every selection cycle, since a certain amount of maintainers was used when basic population was formed and fertile plants selected in following cycles, which were confirmed as hetorozygous in both two fertile restoring loci after progeny test, were come back to the population as pollinator. Therefore, there were abundant of sterile plants for phenotypic selection to establish the recurrent selection population cycle by cycle. (2) After one or two selection cycles, heading date and plant height of most plants had met with breeding objective, and it offered the precondition in later selection for economic and quality character. (3) In this study, the population was continuously improved throughout coming back fertile plants after progeny test to the population as pollinator. At the same time, elites of restoring lines were bred from the recurrent selection population. Restoring P004 and its hybrid 3037 crossed P004 with cms line Yue Feng A, was joined in the on farm demonstration in Jiangsu Province.