以菱白(Zizania latifolia Turcz.)的单季茭品种‘蒋墅茭’和双季菱品种‘葑红早’为试材,进行Cd2+、Pb2+的单一及复合胁迫处理,测定了茭白根系和叶片中的非蛋白巯基(NPT)、谷胱甘肽(GSH)、植物络合素(PCs)的含量,同时测定了茭白植株各亚细胞组分中Cd2+、pb2+的积累量,以探讨茭白对重金属镉、铅胁迫的耐性机理.结果表明:Cd2+、pb2+的单一及其复合胁迫均能促进两菱白品种根系和叶片中NPT、GSH、PCs的含量及菱白各亚细胞组分中Cd2+、pb2+积累量的显著增加；复合胁迫时两茭白品种的NPT、GSH、PCs含量及各亚细胞组分中Cd2+、pb2+的积累量均高于单一胁迫,茭白的不同部位间,以根系中的NPT、GSH、PCs含量显著高于叶片；茭白各亚细胞组分中Cd2+、pb2+的积累量表现为:细胞壁高于原生质体,而可溶性部分高于细胞器.%A single-harvested cultivar,'Jiangshujiao',and a double-harvested cultivar, Fenghongzao', of Zizania latifolia were used as experimental materials to determine the content of non-protein-thiols (NPT), glutathione (GSH), and phytochelatins (PCs). To clarify the tolerance mechanism of Zizania latifolia to Cd2* and Pb2* stress, accumulation of Cd2* and Pb2* in subcellular fractions were also investigated. The results showed that content of NPT, GSH, and PCs and the accumulation of Cd2* and Pb2* in subcellular fractions increased significantly when treated with Cd2* and Pb2* stress. Content was higher when treated with combined stress than single stress. Content of NPT,GSH and PCs were significantly lower in leaves than in roots. The cell wall and the soluble fraction of cells had higher Cd2+ and Pb2+ accumulation levels than the protoplast and the organelles, respectively.
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