铬胁迫对大豆幼苗生理生化特性的影响

Effects of Cr^(6+) Stress on Physiological and Biochemical Properties of Soybean Seedlings

以大豆品种豫豆24号为材料,采用水培法,设置不同的铬(Cr6+)浓度处理,研究了Cr6+胁迫对大豆幼苗生理生化特性的影响。结果表明:随着Cr6+浓度的增加,大豆幼苗的根系和茎叶干重、根冠比、叶绿素含量、叶绿素a/b比值以及超氧化物歧化酶(SOD)活性均呈现下降趋势,而丙二醛(MDA)含量和过氧化物酶(POD)活性逐渐升高。且Cr6+对根系的抑制程度比对茎叶要大,叶绿素a对Cr6+胁迫的敏感程度较叶绿素b大。但低浓度(10 mg/L)Cr6+胁迫对根系和茎叶干重、根冠比、叶绿素含量以及SOD活性的抑制均不明显,MDA含量的增幅较小。表明豫豆24号对低浓度Cr6+毒害具有一定的耐受能力。

By the method of solution culture,and with the soybean （Glycine max L. ） cuhivar Yudou No. 24 as experimental material, this paper studied the effects of different Cr6＋ concentration on the physiological and biochemical characteristics of soybean seedlings. The results showed that with the increasing Cr6＋ concentration supplemented in solution,dry weight of root and shoot, ratio of root to shoot, chlorophyll content, ratio of chlorophyll a to chlorophyll b and superoxide dismutase （SOD） activity in soybean seedlings all decreased,whereas malondialdehyde （MDA） content and peroxidase （POD） activity increased gradually. Furthermore,the inhibition of Cr6＋ stress to root was more serious than to shoot,and chlorophyll a was more sensitive to Cr6＋ stress than chlorophyll b. Under lower Cr6＋ concentration （10 rag/L） stress,root and shoot dry weight,ratio of root to shoot, chlorophyll content and SOD activity were not inhibited obviously, and MDA content increased slightly,suggesting that Yudou No. 24 could tolerate the lower Cr6＋ stress to a certain extent.