镉对玉米苗中钙调蛋白含量和Ca^(2+)-ATPase活性的影响  

Effects of cadmium on calmodulin content and Ca^(2+)-ATPase activities of maize(Zea mays)seedling

作　　者：赵士诚[1] 孙静文[1] 王秀斌[1] 汪洪[1] 梁国庆[1] 周卫[1] 

机构地区：[1]中国农业科学院农业资源与农业区划研究所农业部植物营养与养分循环重点开放实验室,北京100081

出　　处：《植物营养与肥料学报》2008年第2期264-271,共8页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(30471003)资助

摘　　要：试验采用营养液培养的方法,以玉米为试材,研究了不同供镉浓度(0、52、0和100μmol/L)和处理时间(122、4、48、96、168 h)对植株体内钙调蛋白(CaM)含量及生物膜上的Ca2+-ATPase活性的影响。结果表明,植株可溶性Ca2+含量在镉胁迫后较不加镉处理增加,镉处理在叶和根中分别在48和24 h后达最高,然后随镉处理浓度和处理时间的增加逐步下降;同时镉诱导了植株CaM的合成,其含量随镉处理浓度和处理时间增加逐步增加,但20μmol/L和100μmol/L镉处理在168 h后有所下降;与不加镉处理相比,镉胁迫导致植株生物膜上的Ca2+-ATPase活性迅速升高,但随镉处理浓度提高和时间延长,镉胁迫植株的Ca2+-ATPase活性在48 h(质膜、液泡膜和内质网膜)和24 h(线粒体膜)后逐步降低。各膜上的Ca2+-ATPase活性依次为质膜>液泡膜>内质网膜>线粒体膜,且同一微囊膜,根中的活性大于叶中。A hydroponics culture experiment was conducted to examine the effects of cadmium （Cd） stress on calmodulin （CAM） content and Ca2^＋-ATPase activities in maize （Zea mays） plant. Maize seedlings were treated with 0, 5, 20, and 100μmol/L Cd for periods of 12 to 168 h. Results showed that the content of soluble Ca^2＋ in plant were increased by cadmium stress. The highest levels of soluble Ca^2＋ in leaves and roots were found in the plants with 48 h and 24 h exposure to Cd respectively. CaM content in plants was enhanced with increasing Cd concentrations and prolonged Cd treatment. However, CaM content in plants began to decrease after 168 h treatments of 20μmol/L and 100μmol/L Cd. The Ca^2＋ -ATPase activities of Cd stressed plants were higher than that without Cd addition, but they decreased gradually with higher concentrations of Cd and extended Cd treatment after 48 h （plasma, tonoplast and endoplasmic reticulum membrane） and 24 h （mitochondrial membrane）. The decrease of Ca2^＋ -ATPase activities in cell membrane systems showed the following pattern： plasma membrane 〉 tonoplast membrane 〉 endoplasmic reticulum membrane 〉 mitochondrial membrane. The Ca^2＋ -ATPase activities of the same microsomal were higher in root than in leaf.

关 键 词：镉 玉米 钙信使 钙调蛋白 CA^2+-ATPASE 

分 类 号：S513[农业科学—作物学]