缺硫对镉胁迫下水稻幼苗非蛋白巯基物质含量和谷胱甘肽硫转移酶活性的影响

Effects of sulfur starvation on the non-protein thiol content and glutathione S-transferase activity of rice seedlings under cadmium stress

通过设置缺硫(S)处理,研究了镉(Cd)胁迫下水稻生长情况、幼苗Cd和非蛋白巯基含量以及谷胱甘肽硫转移酶(GST)活性的动态变化.结果表明:Cd胁迫明显抑制了水稻生长,显著诱导了巯基物质[非蛋白巯基(NPT)、谷胱甘肽(GSH)、植物螯合肽(PC)]的合成,GST活性表现出先升后降的趋势.缺S处理下,尽管水稻根部对Cd的吸收和向地上部的转运都有所增加,但Cd胁迫程度并未明显增强,巯基物质含量明显降低,根部GST活性提高.表明巯基物质和GST在水稻抗Cd胁迫过程中互为补充,在一定程度上减轻了Cd的毒性效应.

By installing a treatment of sulfur starvation,this paper studied the dynamic changes of rice seedling growth,cadmium（Cd） and non-protein thiol（NPT） contents,and glutathione S-transferase（GST） activity under Cd stress.Cd stress inhibited the seedling growth obviously,induced the synthesis of sulfhydryl（-SH） compounds,including non-protein thiol,glutathione,and phytochelatins,and made the GST activity decreased after an initial increase.Sulfur starvation somewhat increased the Cd uptake and translocation,but less affected the impacts of Cd stress.The contents of-SH compounds decreased,and the GST activity in root increased.It was suggested that the roles of-SH compounds and GST in Cd-resistance of rice were complementary,being able to alleviate the Cd toxicity to some extent.