摘要
研究表明,弱光条件下日光温室黄瓜叶片的Pn、A350、CE、光合作用光饱和点和补偿点均显著降低,表明黄瓜的需光特性与光强环境密切相关。经弱光处理后,黄瓜叶片的Fo、Fv、Fv/Fm、Fs、Fm’及ΦPSⅡ等都增加,表明弱光下PSⅡ的光化学活性和原初光能转化效率提高,用于电子传递的光能比例增加。弱光处理的Chla、Chlb、Chl a/b及类胡萝卜素的含量都降低,Chla和Chla/b的降低幅度显著大于Chlb,即Chlb的相对含量增加,有利于叶片更有效地捕获有限的光能。电镜观察结果表明,弱光下生长的黄瓜叶片栅栏细胞内叶绿体数目及淀粉粒数目成比例减少,叶绿体和淀粉粒减小,叶绿体内基粒数和单个基粒中的片层数增加。
The light characteristics and microstructure of chloroplast of cucumber in solar greenhouse were studied.The result showed that the photosynthetic rate (Pn), photosynthetic ability (A350), carboxylation efficiency(CE), lightsaturation point and compensation point all declined remarkably under low light intensity, indicated that the light characteristicof cucumber is closely related to light enviornment. Under low light intensity, the minimal fluorescence (Fo), alterablefluorescence (Fv), photochemical efficiency of PSⅡ (Fv/Fm), steady fluorescence under light (Fs), maximal fluorescence(Fm) and actual quantum yield of PSⅡ electron transport (ΦPSⅡ) etc. increased, indicated the photochemical activity, theefficiency of light energy transfer and the light energy which used to electron transfer inhanced. The chlorophll a, b, a/b andcarotenoid of low light intensity treatment decreased, and the depressed extent of chlorophll a and a/b were larger thanchlorophll b. The number of chloroplast and starch grain descended as a result of low light intensity, while the number ofgrana and lamella increased. The size of chloroplast and starch grain minished.
出处
《中国农业科学》
CAS
CSCD
北大核心
2004年第2期268-273,共6页
Scientia Agricultura Sinica
基金
国家自然科学基金资助项目(30070458)
山东省自然科学基金资助项目(Y2002D05)
关键词
弱光
日光温室
黄瓜
需光特性
叶绿体
超微结构
Cucumber
Low light intensity
Photosynthetic characteristics
Ultrastructure of chloroplast
