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研究了低温胁迫下水稻幼苗叶绿体光合电子传递功能及类囊体膜蛋白水平的变化。４℃低温结合３５μｍｏｌ／（ｍ２·ｓ）的弱光照处理，使水稻叶绿体全电子链、ＰＳⅡ和ＰＳⅠ的电子传递活性均降低，降低的幅度依次是：全电子链＞ＰＳⅡ＞ＰＳⅠ。对类囊体膜蛋白组分进行的ＳＤＳ－ＰＡＧＥ分析显示，低温使大部分类囊体膜蛋白特别是ＰＳⅡ功能蛋白的稳态水平降低，这可能是造成叶绿体光化学功能降低的主要原因。进一步对低温影响ＰＳⅡ电子传递活性的机理进行了探讨，所得结果表明，低温下ＰＳⅡ功能受抑的主要原因是其氧化侧的电子供应受阻，而与反应中心受到的伤害关系不大，尽管类囊体膜的ＳＤＳ－ＰＡＧＥ结果显示ＰＳⅡ的反应中心也受到低温的损伤。
The photosynthetic electron transfer function and the thylakoid membrane protein level in chloroplasts of rice seedlings under low temperature stress were studied. Under the low temperature of 4 ℃ combined with 35μmol / (m2 · s) of low light, the electron transfer activities of all the electronic chains, PSⅡ and PSⅠ in rice chloroplasts decreased. The decreasing order was: full electron chain> PSⅡ> PSⅠ. SDS-PAGE analysis of the thylakoid membrane protein components showed that low-temperature reduced the steady-state levels of most thylakoid membrane proteins, especially PSII functional proteins, which may be the main reason for the decrease of photochemical function of chloroplasts. Further study on the mechanism of PSII electron transport activity affected by hypothermia showed that the main reason that PSⅡfunction was depressed at low temperature was that the electron supply on the oxidative side was blocked but not on the reaction center, The result of SDS-PAGE showed that the reaction center of PSⅡ was also damaged by hypothermia.