生姜叶片发育过程中光合速率与 MDA 含量及保护酶活性的变化

Changes of Photosynthetic Rate,MDA Content and the Activities of Protective Enzymes during Development of Ginger Leaves

生姜叶片的叶绿素含量与光合速率随叶龄的增大而升高，１５ｄ时达到最高峰，随后降低。叶片展开后４０ｄ内ＭＤＡ含量比较稳定，ＳＯＤ活性稍有升高，ＰＯＤ、ＣＡＴ活性急剧上升；此后ＭＤＡ含量明显提高，ＳＯＤ活性开始下降，ＰＯＤ、ＣＡＴ活性虽仍继续升高，但上升幅度减小，说明生姜叶片叶龄达４０ｄ时开始趋于衰老。

The chlorophyll content and photosynthetic rate(Pn)in ginger leaves increased with leaf expanding and reached a peak on the 15th day at first,then declined gradually.In the first 40 days of the leaves expanding,MDA content of the leaves kept constant,and SOD activity showed a little increase.But after 40 days MDA content increased markedly and SOD activity dropped down.POD and CAT activities exhibited a steady increase during 60 days,but the increment showed a little decrease after 40 days.This result indicated that senescence of ginger leaves might occur when leaf age was about 40 days.