缺硫对万寿菊镉积累的影响  

Cadmium accumulation in Tagetes erecta as affected by sulfur deficiency

作　　者：冯倩[1,2] 付莎莎[1,2] 台培东[1] 李培军[1] 张海荣[1] 张银秋[1,2] 陈扬[1,2,3] 

机构地区：[1]中国科学院沈阳应用生态研究所,沈阳110016 [2]中国科学院研究生院,北京100039 [3]中国科学院高能物理研究所,北京100049

出　　处：《生态学杂志》2009年第9期1818-1823,共6页Chinese Journal of Ecology

基　　金：中国科学院知识创新工程重大项目(KZCX1-YW-06-03);国家重点基础研究发展计划项目(2004CB418506);中国科学院陆地生态过程重点实验室基金;国家高技术研究发展计划资助项目(2007AA061101)

摘　　要：采用营养液培养法,研究了缺硫对万寿菊(Tagetes erecta)各器官镉积累的影响,以及巯基化合物和有机酸等在各器官镉积累中的作用。结果表明:0.1 mg.L-1镉处理7 d,缺硫处理显著降低了植物根、茎和叶中的镉含量,较对照分别降低了47%、38%和61%;缺硫对植物体内半胱氨酸、γ-谷氨酰半胱氨酸、谷胱甘肽和有机酸的合成没有显著影响,而且3种巯基化合物的含量都很低;缺硫植物根部合成的植物络合素的量显著降低,这可能是植物体内镉积累减少的主要原因;在植物的各器官中,叶片中的有机酸含量最高,而在叶片中未检测到植物络合素,由此可推断,叶片中积累的镉主要与有机酸结合;缺硫影响了根部植物络合素的合成,进而降低了植物体内镉的积累,而缺硫没有影响植物体内有机酸的合成,有机酸可能仅是参与植物组织中与镉的络合作用。A hydroponic culture was conducted to study the cadmium （Cd） accumulation in Tagetes erecta as affected by S-deficiency, and to evaluate the roles of thiol compounds and organic acids in the Cd accumulation. After exposure to 0.1 mg Cd · L^-1 for 7 days, the Cd content in T. erecta root, stem, and leaf under S-deficiency decreased significantly by 47%, 38% , and 61% , respectively, compared with the control. S-deficiency had no significant effects on the synthesis of cysteine, γ-glutamyl cysteine, glutathione, and organic acids, and the three thiol compounds were all in lower levels. The synthesized phytochelatins （PCs） amount in S-deficient T. erecta root decreased significantly, which could be the main cause of the reduction of Cd accumulation in the plant. Among the plant organs, leaf had the highest organic acids content but no PCs, suggesting that the accumulated Cd in leaf was mainly bound by organic acids. All the re- sults indicated that S-deficiency affected the synthesis of PCs in root, inducing the decrease of Cd accumulation in plant, but had less effects on the synthesis of organic acids that could possibly participate in the chelation of Cd in plant tissues.

关 键 词：万寿菊 镉 巯基化合物 有机酸 

分 类 号：X173[环境科学与工程—环境科学]