日光温室厚皮甜瓜叶片发育进程中生理生化指标的变化

Changes of Physiological and Biochemical Index of Leaf Development of Muskmelon in Solar Greenhouse

以日光温室栽培的伊丽莎白厚皮甜瓜为试材，探讨了其叶片发育进程中的生理生化指标变化。结果表明，叶龄21d以前，叶片生理功能逐步健全，可溶性蛋白质（Pr）和叶绿素（Chl）含量、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性、光合速率（Pn）不断升高，丙二醛（MDA）含量和过氧化物酶（POD）活性上升缓慢；叶龄21—35d为叶片生理功能缓衰期，各项指标变化相对迟缓；叶龄35—49d为叶片生理功能急衰期，可溶性Pr、Chl含量和Pn迅速下降，MDA含量和POD活性快速升高，SOD、CAT活性急剧下降；叶龄49d以后为叶片衰亡期，生理功能逐渐丧失。

Changes of physiological and biochemical indexes of muskmelon leaves at different growth stage were studied by using muskmelon Yilishabai grown in solar greenhouse. The results indicated that the leaf physiological function got stronger and stronger before 21 days old of leaf age, the contents of soluble protein （Pr）and chlorophyll （Chl）, the activities of superoxide dismutase （SOD） and catalase （ CAT）, and net photosynthetic rate （Pn） increased gradually. At the same time, the content of malondialdehyde（MDA） and the activity of peroxidase （POD）increased slowly. The leaves senesced slowly during 21 -35 days old of leaf age, the parameters mentioned above changed slowly. The leaves senesced rapidly during 35 -49 days old of leaf age. Therefore, the contents of soluble Pr and Chl, and Pn decreased quickly while the content of MDA and the activity of POD increased rapidly, and the activities of SOD and CAT declined sharply. The physiological function of muskmelon leaves lost gradually after 49 days.