【摘要】 田间鉴定了4套玉米CMS-S的同质异核杂交种和不育系的雄花育性表现。发现在保持型F₁群体中有育性部分恢复的不稳定现象。检测它们的线粒体DNA,发现均有游离态的S₁、S₂,类质粒存在。分离恢复型和育性部分恢复的近等基因型F₁植株的线粒体主DNA,经EcoRI等5种核酸内切酶酶切后,与S₁分子探针杂交,均未发现任何带型差异。正常胞质系与不同来源的S胞质不育系的线粒体主DNA经5种内切酶酶切后,与S₁分子探针杂交,带型存在明显差异。而各S胞质不育系之间的带型无差异。结果表明,所研究的CMS-S材料的育性不稳定现象可能与胞质基因无关。更多还原

【Abstract】 The patterns of male-fertility restoration for four CMS-S lines and twelve F1 hybrids from these CMS-S lines testcrossed with three inbred lines, Zifeng 1 (Rf3Rf3). Zifeng 1 (r/3r/3) and 330 respectively were examined. The result showed that all of Ft hybrids between CMS-S lines and their maintainers were partially fertile and the fertility varied with genetic backgrounds, and that high copies of plasmid-like S1 and S2 existed in the mitochondria of all F1 hybrids and CMS-S line. No different banding patterns were discovered between the stable and unstable fertiiky F1 hybrids examined after their main mtDNA digested by five restriction enzymes respectively followed by hybridization with S1 probe from pZmS21, but there were significant differences between main mtDNA of N and S cytoplasm.These results indicated that cytoplasmic genome and plasmid-like S1, S2 were not directly related to the untable fertilitp of CMS-S maize.更多还原