镁对温室黄瓜光合特性的影响  

Effects of Magnesium Stress on Photosynthetic Character of Cucumber in Greenhouse

作　　者：谢小玉[1] 刘海涛[1] 程志伟[1] 

机构地区：[1]西南大学农学与生物科技学院,重庆400716

出　　处：《中国蔬菜》2009年第6期36-40,共5页China Vegetables

基　　金：国家"863"计划项目(2001AA24701);重庆市自然科学基金项目(CSTC2007BB1354)

摘　　要：在温室无土栽培条件下研究了镁对黄瓜开花结果期光合特性的影响。结果表明,多镁胁迫增加了黄瓜叶片叶绿素a、叶绿素b含量,降低了胡萝卜素含量,缺镁胁迫使黄瓜叶片叶绿素a、叶绿素b、胡萝卜素含量均极显著降低,但缺镁胁迫的叶绿素a/b最高;缺镁胁迫下黄瓜叶片净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)的日变化呈单峰曲线变化,而多镁胁迫下Pn和Tr呈双峰曲线;多镁和缺镁胁迫的胞间CO2浓度(Ci)、多镁胁迫的Gs呈近似倒抛物线型;多镁和适镁处理叶片的光饱和点、CO2饱和点以及表观量子效率和羧化效率都大于缺镁处理。缺镁胁迫下黄瓜光合作用主要是受非气孔限制,而多镁胁迫下气孔因素和非气孔因素二者兼具。The effects of magnesium stress on photosynthetic character of cucumber were studied in greenhouse and under soitless condition. The results showed that the contents of chlorophyll a, chloro-phyll b were inecreased, and carotenoids content decreased under Mg-excessive, the contents of chloro-phyll a, chlorophyll b and carotenoids were extremly significantly decreased under Mg-deficiency. Net photosynthesis rate （Pn） , stomata conductance （Gs） and transpiration rate （Tr） changed in one-peak curve under Mg-deficiency, Pn and Tr changed in double peak curve under Mg-excessive. Ci under Mg-excessive and Mg-deficiency, Gs under Mg-excessive changed in inverted parabolic curve in daytime. Light saturation point, CO2 saturation point, apparent quantum yield and carboxylation efficiency under Mg-excessive and Mg-optimum are higher than Mg-deficiency. The main limiting factor of photosynthesis of cucumber seedling is non-stomata factors under Mg-deficiency. They were both stomata and non-stomata factors under Mg-excessive.

关 键 词：黄瓜 镁胁迫 光合特性 

分 类 号：S642.2[农业科学—蔬菜学]