水稻新质源(CMS-FA)雄性不育恢复基因的遗传

Inheritance of Restorer Gene for CMS-FA Hybrid Rice

发掘水稻新型雄性不育细胞质源CMS-FA,育成系列优质米不育系和系列新质源恢复系,在组配成强优势杂交稻组合的基础上,研究新质源雄性不育恢复系的恢复基因遗传。采用新质源(CMS-FA)不育系金农1A与恢复系金恢3号杂交获得杂交F1和F2代种子。用F1分别与不育系或保持系回交,获得(不育系//不育系/恢复系和不育系/恢复系//保持系)2个测交群体。同时种植P1、P2、P3、F1、F2、B1F1和B2F1等群体,考察花粉染色率、套袋结实率和自然结实率,卡平方测验遗传分离适合度。结果表明,不育系与恢复系杂交F1代正常可育,育性恢复(可育)基因为显性遗传。F2代分离出可育︰不育适合3︰1,育性恢复(可育)基因为1对显性基因控制。B1F1和B2F1代2个测交群体的可育︰不育都适合1︰1分离规律,验证了F2代育性恢复(可育)单基因的遗传模式。暂时确定新质源(CMS-FA)核质互作三系的基因型为不育系S(SS)、保持系F(SS)和恢复系S(FF)。

Based on identification of new male sterile cytoplasm （CMS-FA） from wild rice, a series of CMS-FA male sterile lines and restorer lines as well as their hybrid combinations with good quality and strong heterosis were developed. The cross of Jinnong 1A （A line） × Jinhui 3 （R line） was made to study the fertility inheritance of CMA-FA hybrid rice. The F1 generation was backcrossed with the A line and maintainer line （B line） to get two test cross populations （A line//A line/R line and A line/R line//B line）. Totally six populations, namely, P〉 P〉 P3, F1, F2, B1F1, and B2F2, were planted at the same time to evaluate fertility using indexes of stained pollen rate, bagged seed-setting percent, and natural seed-setting percent. The F1 generationshowed a normal condition in fertility, and the F2 generation had a segregation ratio of 3 （fertile）： 1 （sterile） according to Chi-square test. Moreover, the two test-cross populations both had a segregation ratio of 1 （fertile）： 1 （sterile）. The results indicated there was only one domi- nant gene controlling the fertility in the restorer line. Therefore, the genotypes of the three lines of CMS-FA hybrid rice could be tentatively determined as S（SS） for the male sterile line, F（SS） for the maintainer line, and S（FF） for the restorer line.