中文摘要：

【目的】揭示铝诱导根系分泌有机酸的机制，探讨胞质钙信号对铝诱导黑麦根系分泌有机酸的调控作用。【方法】采用药理学研究方法和激光共聚焦扫描显微技术探讨铝胁迫下根尖胞质游离钙离子浓度（[Ca^2＋]cyt）及其与有机酸分泌的关系。【结果】铝不仅诱导黑麦根系分泌柠檬酸和苹果酸，而且使根尖细胞Ca^2＋的荧光强度增强、波动加剧。铝引起的根尖细胞Ca^2＋荧光强度的变化在受Ca^2＋通道抑制剂异搏定、胞内Ca^2＋通道阻断剂辽红干扰后，显著减少了铝诱导的有机酸分泌。铝诱导的根尖[Ca^2＋]cyt的升高及有机酸分泌还受CaM阻断剂三氟拉嗪的干扰和抑制。钙螯合剂EGTA处理不仅减弱了铝诱导的Ca^2＋荧光信号、加大了Ca^2＋信号的波动幅度，而且显著抑制铝诱导的柠檬酸分泌。此外，在铝胁迫下，根系有机酸分泌受阴离子通道抑制剂尼氟灭酸的抑制。【结论】根尖[Ca^2＋]cyt可能是介导铝诱导黑麦根系分泌有机酸的胞内信号因子，而质膜上的阴离子通道可能是铝诱导的钙信号传导途径中的下游效应器。

英文摘要：

[Objective ] The involvement of intracellular Ca^2＋ in regulation of Al-induced secretion of organic acids from roots of rye （Secale cereale L.） was investigated in present study to elucidate the mechanisms for A1 resistance in plants. [Method] In present study, [Ca^2＋]cyt and its involvement in Al-induced secretion of organic acids from roots were studied by pharmacological method and confocal scaning microscopy technology. [ Rresult ] A1 not only induced the secretion of both citrate and malate, but also elevated the levels of [Ca^2＋]cyt of root apices and enhanced the fluctuation of [Ca^2＋]cyt. However, the inhibition of Al-induced secretion of organic acids was followed by the interruption of Al-induced alternation in [Ca^2＋]cyt fulorescence intensity of roots treated with Verapamil or ruthenium red. Moreover, [Ca^2＋]cyt and the secretion of organic acids were also interfered or inhibited by the treatment with Trifluoperazine （CaM antagonist）. Furthermore, Al-induced secretion of citrate was blocked by the treatment with EGTA, which resulted in a wide fluctuation of [Ca^2＋]cyt and a weak Ca^2＋ fluorescence intensity. On the other way, the secretion of organic acids was inhibited by the treatment with anion channel inhibitor, niflumic acid. [Conclusion] These results suggested that root tip [Ca^2＋]cyt might be a signal factor regulating Al-induced secretion of organic acids from roots in rye, while the anion channel of plasma membranes might be an effector in Al-induced Ca-signal transduction pathway.