植物营养与肥料学报2010,16(4)：913-917 Plant Nutrition and Fertilizer Science
环境因素对小麦根系非选择性阳离子通道
（NSCCs）转运钾的影响
王玉倩12，汪晓丽，单玉华，盛海君，封克1.（1扬州大学江苏省扬州农业环境安全技术服务中心，江苏扬州225009
2贵州师范大学生命科学学院，贵州贵阳550001）
摘要：以石家庄8号小麦作为研究对象，通过添加钾载体抑制剂和钾专性通道抑制剂的方法，探讨了温度变化和重金属镉、钢对植物根系的非选择性附离子通道（NSCCs）转运钾离子的影响。结果显示，NSCCs转运钾的最适温度在35℃左右，低温和高温都会使NSCCs的吸钾速率下降。较高的温度（40℃）对NSCCs转运钾的影响大于对专-性钾通道的影响：而较低温度(20℃)对专一性钾道活性的抑制比对NSCCs的抑制更强。重金属镉和铜均对小麦的钾吸收速率产生影响，浓度越大，抑制作用越强。其中，根系NSCCs对锅的敏感度相对于专一性钾通道来说要
低，而对钢的敏感度相对较高。说明不同重金属对两类通道蛋白的影响机制不一样。关键调：钾吸收；非选择性阳离子通道；温度；镭；铜
中图分类号：S512.1.01
文献标识码：A
文章编号：1008-505X(2010)04-0913-05
Effectsofenvironmentalfactorsonnonselectivecation channels-mediatedpotassiumuptakeofwheatroots
WANG Yu-qian'-2, WANG Xiao-li', SHAN Yu-hua', SHENG Hai-jun', FENC Ke'
(I Yangzhou Technical Senice Center for Agro-Entironment Sofety of Jiangsu Protince, Yangzhou Unisersity, Yangzhou 225009,China;
2 School of Life Sciences, Guizhou Normal Unisersity, Guiyang 550001, China)
Abstract: The nonselective cation channels(NSCCs)in plant roots contribute to the potassium transport across cell membrane. However, the ratioa of NSCCs-mediated K + uptake to total K* absorption by crops, and whether this process is affected by the environmental factors are stil unknown. In this paper, the wheat cultivar Shijiazhuang 8 was used as material to study the effects of temperature and heavy metals(cadmium and copper)on K * transport by NSCCs. The results show that the optimum temperature for NSCCs K* uptake is about 35°C , and lower or higher temperature reduces the rate of K * uptake by NSCCs. NSCCs-mediated K * uptake is more sensitive to higher tem-perature(40°C )compared with the specific K * channels, while NSCCs-mediated K * uptake is more tolerant to low er temperature(20C ). The effects of cadmium and copper on NSCCs-mediated K * uptake are dependent on their concentrations. Compared with the specific K* channels, NSCCs are less sensitive to Cd2+ and more sensitive to Cu2+, which indicates that different heavy metals may influence the two types of channel proteins in different ways. Key words: potassium uptake; nonselective cation channels(NSCCs); temperature; cadmium; copper
钾离子是高等植物体内含量最多的阳离子，在维持细胞膨压、调节阴阳离子平衡、增强光合作用、增强植物体内物质合成和转运、提高植物抗性、改善品质、提高储藏性等方面均起着重要作用（)。然
收稿日期：2009-0622
接受日期：2010-01-14
基金项目：国家自热科学基金项目（3067240，30871588）资助。
而，一些土壤所能提供的钾素远不能满足植物生长的需要，因此，植物尤其是农作物对钾的吸收问题一直是植物营养领域的研究热点。
植物体内的钾离子转运途径包括高亲和转运系
作者简介：王玉债（1979—），女，河北石家庄人，博土研究生，主要从事植物营养生理研究。E-mail；wangyuqjiancal@163，com
*遇讯作者 Tel;051487979588,E-mail:fengke@ yau.edu.cn
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