水稻黄叶突变体的剑叶衰老与保护酶活性关系的研究

LEAF SENESCENCE AND PROTECTIVE ENZYME ACTIVITIES OF A XANTHA MUTANT RICE(Oryza sativa L.)

以野生型龙特甫B为对照，研究了其黄叶突变体黄玉B剑叶衰老与抗氧化酶活性的关系。结果表明，在花后5～25d，黄玉B剑叶的叶绿素、蛋白质含量的降低以及丙二醛（MDA）的增加幅度明显比龙特甫B慢，其酶促防御系统的保护酶超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）活性变化小，相对稳定，清除衰老过程中产生的活性氧自由基的能力强。本文还对水稻衰老生理指标判断的方法进行了探讨。

The relationship between leaf senescence and the activities of protective enzymes was studied through comparion of a xanthan rice mutant HuangyuB with its wild type parent Longtefu B. During 5 - 25 days after flowering, compared to the wild type the decreases in the contents of chlorophyll and protein, and increases in the content of malondialdehyde （MDA） were significantly slower in the mutant. The activities of three protective enzymes, superoxide dismutase （SOD）, peroxidase （POD） and catalase （CAT）, were relatively stable in the mutant, indicating the stronger ability in removing free radicals and active oxygen in HuangyuB than the wild type. The criterion of rice senescence was also discussed.