不同耐性大豆品种根系对低钾胁迫的生理响应  

Root Biological Responses of Low Potassium Tolerance and Sensitive Soybean Varieties to Low-potassium Stress

作　　者：李兴涛[1] 王伟[1] 蒋春姬[1] 李春红[1] 曹敏建[1] 

机构地区：[1]沈阳农业大学农学院,辽宁沈阳110866

出　　处：《大豆科学》2010年第5期800-803,共4页Soybean Science

基　　金：辽宁省科技厅博士启动研究资助项目(20061041);沈阳农业大学基金资助项目(2006109)

摘　　要：以耐低钾型品种沈农6和低钾敏感型品种铁丰31为材料,通过砂培试验研究了不同低钾耐性大豆品种根系对低钾胁迫的生理学响应。结果表明:低钾胁迫下敏感型品种根系伤流液量和阳离子交换量较高钾处理显著降低,耐性品种处理间没有明显变化。低钾胁迫下两品种根系质膜H+-ATPase活性显著提高,耐性品种表现尤为突出。此外,低钾胁迫下不同耐性品种Km值降低,耐性品种降低幅度大于敏感品种;两品种Imax在低钾胁迫下有不同程度的提高,敏感品种增幅大于耐性品种;两品种临界浓度Cmin值在低钾胁迫下也发生显著变化,耐性品种增加幅度极为显著。Low-K sensitive and low-K tolerant Soybean[ Glycine max （L.） Merr. ] varieties, Tiefeng31 and Shennong6, were used to study the root biological responses to low-potassium stress by sand culture in the presence of 0.5 and 3.0 mmol · L - 1 K. After 25 d of growth, cation exchange capacity （CEC） , bleeding sap, H ＋ -ATPase and kinetics of potassium uptake of root were investigated. The results showed that root bleeding sap and CEC of sensitive variety were all declined under low K stress, while that of tolerant variety changed slightly under K deficiency condition. The plasma membrane H ＋ -ATPase activi- ties were much higher than those at adequate K supply, especially to tolerant variety. Furthermore, the sensitive variety was superior over the tolerant variety both in uptake speed and time. Potassium kinetic studies indicate that K deficiency in plants resulted in a decrease in Km value and an increase in Imax, and Cmin values. However, the change extent of each parameter was harshly different between tolerant and sensitive varieties.

关 键 词：大豆 耐低钾 根系 阳离子交换量 质膜H+-ATPase IMAX 

分 类 号：S565.1[农业科学—作物学]