摘要
采用水培方法,研究了不同钒(V)浓度(0、5、10、20、40 mg·L^(-1))胁迫后,甜玉米幼苗地上部和地下部谷胱甘肽(GSH)、植物螯合肽(PCs)、非蛋白巯基(NPT)和类金属硫蛋白(MTL)含量的变化。结果表明,随着V胁迫浓度升高,植株地上部与地下部中GSH含量均先升高后下降,PCs含量和NPT含量则先下降后上升,MTL含量呈现上升的变化趋势。地上部是GSH的主要存在部位,而地下部是PCs、NPT和MTL的主要存在部位。当V胁迫浓度为10 mg·L^(-1),地上部GSH含量达最大,比对照增加18.86%;V胁迫浓度为5 mg·L^(-1),地下部PCs含量达最低,比对照组降低了14.93%,地下部NPT含量比对照组下降4.27%,随着V胁迫浓度的增加,NPT含量增大,当V胁迫浓度为40 mg·L^(-1),地下部MTL含量比对照组增加12.31%。外源V对植物PCs的合成与GSH变化呈现消长关系,表明受到重金属胁迫后GSH含量由于PCs的合成而下降,GSH和PCs在植物不同部位承担着对重金属的解毒功能。NPT是螯合重金属离子的重要物质,MTL中有大量的巯基,可结合重金属离子以减轻其对植物的毒害作用。地下部NPT和MTL含量增加,表明玉米幼苗根部是抵御重金属毒害的重要部位。
The effects of different vanadium（V） press levels concentrations （0, 5, 10, 20, 40 mg·L^-1 ） on the contents of glutathione （GSH）, phytochelatin （PCs）, non-protein thiol （NPT） and metallothionein （MTL） were investigated by hydroponic method after 7 d in sweet maize seedlings both in shoots and underground parts. The results showed that with the increase of V press level, the contents of GSH in sweet maize seedlings both in shoots and underground parts increased first and then decreased.The contents of PCs and NPT decreased first, then increased, while content of MTL increased. GSH existed mainly in the shoots, but PCs, NPT and MTL existed mainly in the underground parts. Compared to the control, the GSH content of shoots reached the maximum, increased by 18.86% when V press level was 10 mg·L^-1 . PCs content reached the lowest in the underground parts, decreased by 14.93%. NPT content decreased by 4.27% when V press level was 5 mg·L^-1 . MTL content in the underground parts increased by 12.31% when V press level was 40 mg·L^-1 .Exogenous V has effect on the relation between the syntheses of PCs and change of GHS. Content of GSH would decline because of syntheses of PCs by the heavy metal press. GSH and PCs in different parts of plants bear the function of detoxification of heavy metals. NPT is an important material for chelating heavy metal ions.There are large numbers of thiol in MTL, both of them can combine with heavy metal ions to reduce its toxic effects on plants. The contents of NPT and MTL in roots increased, which indicated that the root of maize seedling was an important part to resist heavy metal toxicity.
作者
侯明
李明沅
杨心瀚
HOU Ming;LI Ming-yuan;YANG Xin-han(a.College of Chemistry and Bioengineerin;b.Key Laboratory of Food Safety and Detection in Guangxi Colleges and Universities,Guilin University of Technology,Guilin 541004,Chin)
出处
《桂林理工大学学报》
CAS
北大核心
2018年第2期329-334,共6页
Journal of Guilin University of Technology
基金
国家自然科学基金项目(41161076
41561077)
广西自然科学基金创新研究团队项目(2015GXNSFFA139005)
关键词
甜玉米
钒
植物螯合肽
谷胱甘肽
非蛋白巯基
sweet maize
vanadium
plant chelating peptide（PCs）
glutathione（GSH）
non-protein thiol （NPT）
