温敏核不育基因在籼型三系遗传背景下的育性表达

用3个温敏核不育系培矮64S、6311S和360S与7个籼型质核互作型水稻雄性不育系及相应的保持系、3个恢复系配组，观察了51个组合的F1、19个F2及6个BC1的育性表现。结果表明：培矮64S温敏核不育性状由2对隐性基因控制，具有对质核互作型雄性不育系育性的强恢复基因；6311S温敏核不育性状由1对隐性基因控制，同时具有1对弱恢复基因；360S温敏核不育性状由1对隐性基因控制，但没有恢复基因。进一步利用4个细胞质雄性不育系/6311S组合F2群体中4个温敏核不育株与5个细胞质雄性不育系CMS配组，研究了杂交F1的育性，表明在可育细胞质背景下，三系恢复基因对温敏核不育基因的表达没有影响；在不育细胞质背景下，三系恢复基因是温敏核不育基因表达的关键。由此提出了选育不育细胞质背景的光温敏核不育系和温敏核不育背景的质核互作型不育系的策略。

Fertility Expression of Thermo-Sensitive Genic Male Sterile Genes under the Backgrounds of indica Cytoplasmic Male Sterile Lines, Restorer Lines and Maintainer Lines

Fertilities of generations of 51 F₁ , 19 F₂ and 6 BC₁ derived from 3 thermo-sensitive genic male sterile lines(TGMS-lines) Pei′ai 64S, 6311S and 360S and three-lines including 7 indica cytoplasmic male sterile lines(CMS-lines) and their corresponding maintainer lines(B-lines) and 3 indica restorer lines(R-lines) were investigated to study the expression of TGMS-genes under the backgrounds of the three-line. The TGMS trait of Pei′ai 64S was governed by 2 pairs of independent recessive genes and Pei′ai 64S had stronger fertility restoring(Rf) genes for CMS-lines; The TGMS trait of 6311S was conferred by a single recessive gene and 6311S had a pair of weaker Rf-gene;the TGMS trait of 360S was controlled by a single recessive gene and 360S had no Rf-gene. After studying on the fertility of F₁ plants between 5 CMS-lines and 4 TGMS generations selected from F₂ plants of 4 CMS-lines/6311S, it was confirmed that the expression of TGMS-gene was controlled by Rf-gene under the background of CMS, but not affected by Rf-gene under the background of normal fertile cytoplasm. The potential breeding strategies of TGMS-lines under the background of CMS and CMS-lines with the nucleus of TGMS-genes were discussed.