摘要： 为了探究不同浓度镉胁迫对棉花幼苗非蛋白巯基肽类（NPT）、植物螯合肽（PCs）、金属硫蛋白（MT）和谷胱甘肽（GSH）等含巯基类物质与镉胁迫毒理的内在联系，在漂浮育苗条件下，对镉（Cd）积累不同的棉花品种单16和11-20进行研究。结果表明，Cd处理提高了棉苗根、茎和叶中NPT和PCs含量。根中NPT含量11-20显著低于单16，茎中NPT含量则11-20显著高于单16，叶中NPT含量在镉处理浓度由150 μmol/L提高到300 μmol/L时，两品种根中NPT含量增加，茎中NPT含量略有下降，而在叶片中的NPT含量，表现为单16略增加，11-20略降低。棉苗根中GSH含量表现为先增后减，茎中则表现为先减后增，均为11-20品种GSH含量高于单16。棉苗各器官中PCs含量随着镉浓度的增加而增加。棉苗根和叶中PCs含量均为单16显著高于11-20，茎中PCs含量则相反。2个棉花品种NPT、PCs和GSH含量均表现为根 > 茎 > 叶。Cd处理显著提高了棉苗根、茎和叶中MT含量，均表现为叶 > 茎 > 根。11-20的MT含量显著高于单16，较高的镉浓度（300 μmol/L）处理可诱导棉苗MT合成量增加。

关键词: 棉花, 非蛋白巯基肽类, 植物螯合肽, 谷胱甘肽, 金属硫蛋白

Abstract: Using cadmium (Cd) to accumulate a variety of cotton varieties Dan 16 and 11-20,the effects of different concentrations of cadmium stress on cotton seedling were studied under the condition of floating seedling seeks to investigate the relationship between Cd toxicity and the content of non-proteinthiol(NPT), phytochelatins(PCs),glutathione(GSH) and metallothionein (MT).The results showed that the content of NPT and PCs had improved under the Cd treatment, which in cotton seedling's root, steam and leaves. The content of NPT in roots of 11-20 was significantly lower than that of Dan 16,while in the opposite of the stems. The content of NPT in leaves increased slightly when the concentration of cadmium was increased from 150 μmol/L to 300 μmol/L. The content of GSH in cotton seedlings was increased first and then decreased, while in the stem was decreased first and then increased, and the contents of GSH in 11-20 were higher than Dan 16. The content of PCs in the organs of cotton seedlings increased with the increased of cadmium concentration. The content of PCs in the root and leaf of cotton was significantly higher than that of 11-20, and the content of PC in stem was opposite. The content of NPT, PCs and GSH in cotton seedlings showed root > stem > leaves. Cd treatment significantly increased MT content in roots, stems and leaves of cotton seedlings, all showed leaf > stem > root. The content of MT in 11-20 was significantly higher than Dan 16, the higher Cd concentration (300 μmol/L) could induce the increase of MT synthesis in cotton seedlings.

Key words: Cotton, Non-proteinthiol, Phytochelatins, Gultathione, Metallothionein

中图分类号: 

• S562.01