萝卜营养生长期超氧化物歧化酶活性和丙二醛含量的变化

研究了不同品种萝卜营养生长期其超氧化物歧化酶 ( SOD,EC1.15.1.1)活性及丙二醛( MDA)含量的变化。结果表明 :不同品种萝卜及同一品种萝卜在不同营养生长期其 SOD活性存在较大差异 ,SOD活性随叶龄的增大而升高 ,4 0 d时达最大峰值 ,随后下降 ;MDA含量在叶片展开后 4 0 d内缓慢上升 ,此后明显升高。SOD活性低的萝卜品种其丙二醛含量高 ,萝卜肉质根的 SOD活性高于叶片的 SOD活性。说明萝卜营养生长期存在活跃的活性氧代谢 ,SOD活性降低可能是引起 MDA含量升高的原因之一。

Changes of superoxide dismutase activities and MDA contents in radish during vegetative growth period

The changes of superoxide dismutase(SOD,EC 1 15 1 1) activities and MDA contents in different varieties of radish during vegetative growth period were studied. The results indicated that there were great differences in SOD activities among different varieties of radish or different growth stages in the same variety of radish. SOD activity increased gradually and reached peak value when leaf instar was 40 days and then decreased; MDA contents increased slowly within 40 days after leaf developing and then increased evidently. The variety of radish with high SOD activity had low MDA content. SOD activities were higher in radish root than that in radish leaf. These suggested that the active oxygen metabolism in radish during vegetative growth period was active and SOD activity decreasing may be one reason of increase in MDA content.