铬胁迫对青菜（Brassica chinensis L.）植物螯合肽含量及抗氧化特性的影响

选用不同耐铬胁迫青菜品种春油1号和青伏令,采用不同浓度Cr3＋处理,测定青菜抗氧化酶活性及植物螯合肽含量等生理指标。结果表明,随着Cr3＋处理浓度升高,两种青菜叶片抗氧化酶活性、酸溶性SH、植物螯合肽（PCs）及谷胱甘肽（GSH）含量均呈增加趋势（P〈0.05）,高浓度Cr3（＋300 mg.L-1）处理下,耐铬胁迫较弱的青伏令叶片SOD、POD、CAT活性分别比对照增加了24.2%、41.7%、21.4%,耐铬胁迫较强的春油1号分别比对照增加了37.2%、70.7%、43.0%,并且PCs含量是对照的3.17倍,明显高于耐铬胁迫较弱品种青伏令（1.71倍）。Cr3＋处理下耐铬胁迫较强的青菜品种春油1号表现出相对较高的抗氧化酶活力及非酶物质含量,不同品种青菜对铬胁迫的生理差异较大。

Effects of Chromium Stress on the Content of Phytochelatins and Antioxidative Characteristics in Brassica chinensis L.

The content of phytochelatins and the activities of antioxidative enzymes in varieties of Chunyou 1 and Qingfuling were investigated by hydroponic experiments.The results showed that the activities of antioxidant enzymes and the content of acid soluble SH,phytochelatins（PCs） and reduced glutathione（GSH） increased with the increase of Cr3＋ concentration for varieties of Chunyou 1 and Qingfuling（P0.05）;Under the concentration of 300 mg·L-1 Cr3＋ treatment,the activities of superoxide dismutase（SOD）,peroxidase（POD）,catalase（CAT） in Qingfuling were 24.2%,41.7% and 21.4% higher than control,and the activities of these enzymes in Chunyou 1 were 37.2%,70.7%,43.0% higher than control,respectively,PCs content was 3.17 times as much as control in Chunyou 1,and it was 1.71 times as much as control in Qingfuling.Chunyou 1 was more Cr-resistance than Qingfuling and appeared higher activities of antioxidative enzymes and content of PCs.The physiological respondence varied significantly between different varieties of Brassica chinensis L.under Cr3＋ stress.