两种生态型芦苇叶绿体的光合电子传递和抗氧保护体系  

Photosynthetic Electron Transport and Anti-oxidative System in Two Ecotypes of Reed

作　　者：朱学艺[1] 张承烈[1] 

机构地区：[1]兰州大学生命科学学院,兰州730000

出　　处：《植物生理学报（0257-4829)》2000年第6期476-480,共5页Acta Phytophysiologica Sinica

基　　金：国家重点基础研究专项经费资助 (G19990 1170 0 )

摘　　要：分布于甘肃省河西走廊的两种不同生态型芦苇———水生芦苇 (水芦 ,生长在深约 1m的水滩里 )和沙丘芦苇 (沙芦 ,生长在高约 5m的沙丘上 )在其离体叶绿体的光化学活性上表现为前者高于后者。其中 ,沙芦全链电子传递速率及光系统Ⅱ (PSⅡ )电子传递速率明显低于水芦 ,而光系统Ⅰ (PSⅠ )电子传递速率却与水芦接近。沙芦叶片和叶绿体中抗氧化酶活性及叶片抗坏血酸含量均高于水芦。综合结果表明 ,喜水植物芦苇登陆后 ,在自然选择压力下 ,为适应长期的自然干旱胁迫环境 。Comparative studies were conducted on some photochemical properties and chlorophyll fluorescence of chloroplasts and activities of the main anti oxidative components in two ecotypes of reed ( Phragmites communis T.), swamp reed (SR) and dune reed (DR), growing in the Hexi corridor, Gansu Province. Electron transport rates for whole chain and photosystem Ⅱ (PSⅡ) in chloroplasts from DR were remarkably lower than those from SR, being 55.6% and 72.5%, respectively (Table 2). However, the electron transport rate for photosystem Ⅰ ( PS Ⅰ ) in DR chloroplasts was 91.8% as that in SR (Table 2). The superoxide dismutase ( SOD ) activities of the leaves and of chloroplasts in DR were higher than those in SR, the latter showing marked difference, DR is 3.3 times as high as that in SR. Specific activity of ascorbate peroxidase (APX) in DR chloroplasts was 1.9 fold higher than in SR's. Besides, DR had a higher level of ascorbic acid (AsA) than SR (Table 3). These results suggest that when reed, as a hydrophyte plant, is subjected to intense selection pressure in dune habitat, DR chloroplastic anti oxidative system plays an important role in protecting photosynthetic apparatus from oxidative damage caused by water stress.

关 键 词：生态型芦苇 干旱 光合电子传递 抗氧保护成分 

分 类 号：S564.2[农业科学—作物学]