Abstract: With high light, differences of pigment photobleach in 54 varieties observed under low CO₂ and O₂ (in water) showed that these varieties could be divided into 4 groups: Ⅰ. The resistant type which included 6 varieties with higher Chl and Car contents in photooxidation; Ⅱ. The sensitive type including 13 varieties with lower Chl and Car contents; Ⅲ. The specific type, having 3 varieties with higher Car but lower Chl contents: Ⅳ. The intermediate type. There were 32 varieties and their Chl and Car contents were intermediate. Under normal condition, the contents of Chl or Car and the ratio of Chl a/b or Car/Chl in the resistant type were lower than those in the sensitive one, and there were the linear correlations between the contents of Chl and Car as well as Chl a and Chl b in each type. However, treated by photooxidation the content of Chl or Car, the ratio of Chl a / b and SOD activity all decreased while only the ratio of Car/Chl rose in the four types. But these changes in the resistant type were less in comparison with the other types except the SOD activity. This indicated that the relative stability of pigment components characterized the resistance of indica rice to photooxidution which seemed to be the better function of SOD in scavenging the active oxygen.

Key words: High light, Indica varieties, Pigment photobleach

摘要： 在光氧化条件下(强光、低CO2 低O2)调查了 54个籼稻品种叶绿素（chl）和类胡萝 素（Car）的光漂白差异，并根据这些特点划分为4类。I） Chl和Car含量都较高的耐光氧化类型（6个）；II) 两者都较低的不耐光氧化类型(13个)；III） Chl含量较高而Car含量较低的持殊类型(3个)；两者含量介于中间的中间类型（32个）。在正常条件下，耐光氧化类型的Chl、 Car含量以及Chla，b、 Car／Chl值都较不耐的低。各类型中的Chl与Car、Chl a与Chl b之间都呈线性关系。但经光氧化处理后，各类型的Chl、Car含量，Chl a／b值和SOD 活性都下降，只有Car/Chl值上升。耐的类型除SOD活性变化较大外，其他参数变化较少。这似乎说明色素组分的相对稳定是耐光氧化的一个特性，且与SOD清除活性氧功能有关。

关键词: 籼稻, 叶片, 色素, 光合作用, 强光