牡山羊草细胞质小麦核代换系酶活性及其与花粉败育的关系

Relationship Between Microspore Abortion and Activities of Superoxide Dismutase(SOD) and Catalase(CAT) of Wheat Nuclear Sustitutional Lines in Ae.juvenalis Cytoplasm

对牡山羊草细胞质小麦核代换系在花药发育的不同时期的超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)活性研究表明 ,牡山羊草细胞质小麦核代换系 SOD、CAT的酶活性在二核期之前与其核供体普通小麦差异很小 ,呈下降趋势 ,二核期以后核代换系 SOD、CAT的酶活性急剧下降 ,到三核期均显著低于其核供体普通小麦 ;核代换系表现不同程度的雄性不育 ,其育性普遍低于其核供体普通小麦 ,核代换系的育性与其 SOD、CAT的酶活性呈正相关关系 ;牡山羊草细胞质小麦核代换系花粉败育的关键时期是二核期至三核期 ;花粉败育的根本原因是异质系核质关系不协调、酶代谢失调 ,导致 SOD和 CAT活性下降、活性氧积累、膜系统损伤。

Common wheat and their nuclear substitutional lines in Ae. juvenalis Cytoplasm were selected to study the activities of Superoxide Dismutase(SOD) and Catalase(CAT) in penultimate leaves and anthers at different development stages of pollens. The results showed that there were little difference between SOD and CAT activities of nuclear substitutional lines and those of common wheat before the dinucleate stage, and theirs were all decreased. After the dinucleate stage, SOD and CAT activities of nuclear substitutional lines decreased rapidly and their activities of CAT and SOD were lower markedly than those of common wheat at the time of thinucleate stage. There was difference among the male sterilities of the nuclear substitutional lines whose fertilities were generally lower than those of nuclear donor, and there was significantly positive correlation between the fertilities and SOD and CAT activities of nuclear substitutional lines. The periods of dinucleate stage and thinucleate stage were the key periods of microspore abortion. The radical reason resulting in microspore abortion of alloplasm was disorder between nucleus and cytoplasm, which caused unbalance of enzymatic metabolism, decrease of activities of SOD and CAT, and damage of membrane systems led by accumulated active oxygen.