Physiological Basis of Photosynthetic Tolerance to Photooxidation and Shading in Rice  

水稻耐光氧化和耐荫特性的生理基础(英文)

作　　者：李霞[1] 焦德茂[1] 

机构地区：[1]江苏省农业科学院农业生物遗传生理研究所,南京210014

出　　处：《Acta Botanica Sinica》2000年第12期1271-1277,共7页Acta Botanica Sinica（植物学报：英文版）

基　　金：ChinaStateKeyBasicResearchandDevelopmentPlan (G19980 10 10 0 )

摘　　要：Thirty genotypes from rice germplasm were identified under photooxidation and shading condition and divided into four basic types : (1) cultivars tolerant to both photooxidation and shading, (2) cultivars tolerant to photooxidation but sensitive to shading, (3) cultivars tolerant to shading but sensitive to photooxidation, and (4) cultivars sensitive to photooxidation and shading. A comparative study of photosynthetic characteristics of a cultivar (cv. Wuyujing 3) that is tolerant and a cultivar (cv. Xiangxian) that is sensitive to both photoinhibition and shading showed that the photochemical efficiency of PSⅡ ( F v/F m ) and the content of PSⅡ_D1 protein in the tolerant cultivar “Wuyujing 3” decreased less under photoinhibition conditions as compared with “Xiangxian”. Under photooxidation conditions, superoxide dismutase was induced rapidly to a higher level and the active oxygen O - built up to a lower level in “Wuyujing 3” than in “Xiangxian”. At the same time, the photosynthetic rate decreased by 23% in “Wuyujing 3” vs. 64% in “Xiangxian”. Shading (20% natural light) during the booting stage caused only small decreases (7%-13%) in RuBisCO activity and the photosynthetic rate in “Wuyujing 3” but showed marked decreases (57%-64%) in “Xiangxian” which corresponded to the decreases in grain yield in the two cultivars (38% and 73%, respectively). The correlation analysis showed that the tolerance to photooxidation is mainly related to PSⅡ_D1 and that to shading is mainly related to RuBisCO activity. This study provided a simple and effective screening method and physiological basis for crop breeding in enhancing tolerance to both high and low radiation.用简易、有效的人工光氧化和遮荫技术对 30个水稻 (OryzasativaL .)种质进行筛选 ,鉴定出既耐光氧化又耐荫、耐光氧化不耐荫、耐荫不耐光氧化、既不耐荫又不耐光氧化等 4种品种类型 ,并用既耐光氧化又耐荫的品种“武育粳 3号”和对光氧化和遮荫均敏感的品种“香籼”进行光合特性研究。结果表明 :在遮荫条件下 ,与对光氧化和遮荫敏感的品种“香籼”比较 ,“武育粳 3号”的PSⅡ活性差异不大 ,RuBisCO活性降低较少 ,光合能力、光合生产力较高。在光抑制条件下 ,“武育粳 3号”的PSⅡ活性 ,PSⅡ光化学效率 (Fv/Fm) ,PSⅡ_D1蛋白含量降低较少 ,光合作用光抑制较轻。在光氧化条件下 ,内源活性氧清除剂SOD诱导活性高 ,清除O-能力强 ,因而叶绿素衰减较慢。上述研究为水稻育种提供了配套的优良生理特性的鉴定技术和生理依据。

关 键 词：PHOTOOXIDATION SHADE RICE PSⅡphotochemical efficiency RuBi0 

分 类 号：Q945.11[生物学—植物学]