作　　者： ; ; ; ; ;

机构地区： 昆明理工大学环境科学与工程学院

出　　处： 《生态学杂志》 2012年第5期1233-1240,共8页

摘　　要： 采用反相高效液相色谱(RP-HPLC)法,研究了水培条件下3种形态砷[三价砷As(Ⅲ)、五价砷As(V)和二甲基砷(DMA)]的5个处理浓度(0、0.3、1.0、3.0和5.0mg·L-1)对黑藻(Hydrillaverticillata(L.f.)Royle)砷吸收和植物络合素(PCs)合成的影响。结果表明:黑藻对As表现出明显的吸收和富集效应,低浓度As能促进黑藻生长,对As(Ⅲ)的吸收显著高于As(V)和DMA;As(Ⅲ)和As(V)处理显著诱导了谷胱甘肽(GSH)、PC2和PC4的合成,且与黑藻体内As含量呈显著正相关(P<0.05);PCs对DMA处理不敏感,只有在0.3mg·L-1下能合成PCs;在As(Ⅲ)处理下,GSH和PC2的合成随As(Ⅲ)浓度的增加呈先增加后减少的趋势,而PC4的合成却随As(Ⅲ)浓度的增加而增加;在As(V)处理下,GSH的合成随As(V)浓度的增加呈先增加后减少的趋势,而PC2和PC4的合成则随As(V)浓度的增加而增加;在3种形态As的不同浓度处理中PC3的合成很少,只在0.3mg·L-1下有少量合成。研究结果表明,PCs对As(Ⅲ)和As(V)的胁迫较敏感,可选择性地作为这2种形态砷胁迫下黑藻的生物标记物。 A hydroponic experiment was conducted to study the effects of different arsenic species ／[As（Ⅲ）, As（V）, and DMA／] at five concentrations （0, 0.3, 1.0, 3.0, and 5.0 mg·L-1） on the arsenic uptake and phytochelatins （PCs） synthesis by Hydrilla verticillata. The PCs contents were identified by reversed phase-high performance liquid chromatography （RP-HPLC）. H. verticillata had an obvious arsenic uptake and accumulation. Low concentrations arsenic promoted the growth of H. verticillata, and the uptake of As（III） by H. verticillata was significantly higher than that of As（V） or DMA. As（Ⅲ） and As（V） promoted the synthesis of GSH, PC2, and PC4 significantly, and the synthesis was significantly positively correlated with the arsenic concentration in H. verticillata （P0.05）. DMA had little effects on the synthesis of PCs, with a detectable synthesis only at 0.3 mg·L-1 of DMA. With increasing concentration of As（Ⅲ）, the synthesis of GSH and PC2 decreased after an initial increase, but the synthesis of PC4 increased. W ith the increasing concentration of As（V）, the synthesis of GSH increased first and decreased then, while the synthesis of PC2 and PC4 presented an increasing trend. Very few PC3 was synthesized in all treatments except at 0.3 mg·L-1 of the test arsenic species. This study indicated that the synthesis of PCs was sensitive to the stress of As（Ⅲ） and As（V）, and the PCs could be used as an biomarker indicating the stress of these two As species on H. verticillata.

关 键 词： 重金属 砷胁迫 黑藻 植物络合素

领　　域： [生物学]