新老水稻品种抽穗后叶片保护酶活性的变化及其与光合速率的关系

目的]为水稻优良杂交亲本选择提供依据。方法]研究了吉林省在20世纪50和90年代育成的8个水稻品种在水稻抽穗后叶片SOD、POD、CAT和MDA含量的变化以及保护酶活性与光合速率、产量之间的关系。结果]在抽穗后20、30d,新品种水稻叶片SOD活性和POD活性在0.05水平显著高于老品种;齐穗期和齐穗后10d,新品种水稻叶片CAT活性在0.05水平显著高于老品种,齐穗后新品种水稻叶片MDA含量均低于老品种。相关分析结果表明,灌浆期叶片SOD、POD和CAT活性与叶片光合速率呈正相关,叶片MDA含量与光合速率呈负相关。新育品种抽穗后叶片保护酶活性增强,可延缓水稻开花后叶片衰老,增强光合速率,提高结实率和产量。结论]齐穗后叶片保护酶活性可作为水稻优良杂交亲本选择的参考指标。

Research on Changes of Protective Enzyme Activity and Relationship with Photosynthetic Rate in Rice Leaves of Old and New Varieties after Heading

Objective]The research aimed to provide the basis for the selection of the hybrid parent.Method]With the representative of eight varieties of Jilin Province cultivated in the 1950s and 1990s,the changes of superoxide dismutase,catalase,peroxdase activity and malondialdehyd content were investigated after heading and the relationship between protective enzyme activity and photosynthetic rate,grain yield were analyzed.Result]SOD and POD activity of the new rice varieties were higher than those of the old rice varieties in 20 and 30 days after heading.SOD and POD activity of the new rice varieties were higher than those of the old rice varieties in 10 d after heading and heading.MDA content of the new rice varieties were lower than that of the old rice varieties after heading.Photosynthetic rate was positive correlated with SOD,POD and CAT activity of leaf after heading,and was significantly negative correlated with MDA content of the leaf.The activity increase of protective enzyme of rice leaf would delay the rice leaf senescence after flowering,enhance photosynthetic capability and raise seed setting percentage and grain yield.Conclusion]The research provided an evidence for protective enzyme activity as selection indexes of grain yield in future rice breeding.