论文部分内容阅读
以小麦品种川育12,川麦42,川麦47和小观54-2为材料,生长15 d后用200μmol/L CdCl_2水培小麦幼苗,研究镉(Cd)胁迫对不同品种小麦幼苗抗氧化酶类活性的影响.结果表明,Cd胁迫4 d的情况下,四个小麦品种的抗氧化酶类活性没有受到较大影响,品种间也无明显区别.但在Cd胁迫8 d时,川育12受镉胁迫最为严重,生长最差,丙二醛(MDA)含量明显升高,电导率也大幅度上升,抗氧化酶类活性也受到不同程度的影响,超氧化物歧化物(SOD),过氧化物酶(POD),抗坏血酸过氧化物酶(APX)和谷胱甘肽过氧化物酶(GPX)活性均受到强烈抑制.相反,川麦47和小观54-2两个品种表现出对镉较强的耐受性,Cd胁迫下MDA和电导率都没有明显改变,且保持有较高的绝对含水量,抗氧化酶类活性也随着Cd胁迫时间的加长而受到诱导增强.此外,四个品种均在根部积累了较多的镉离子,叶片中积累很少.镉离子积累量顺序依次是:川育12>川麦42>川麦47>小观54-2.因此可以推测,吸收较多的镉对抗氧化酶类活性形成抑制作用,从而也说明了不同小麦品种对镉的抗性机理的不同.
The wheat cultivars Chuanyu 12, Chuanmai 42, Chuanmai 47 and Xiaoyaoguan 54-2 were used as experimental material to study the effects of cadmium (Cd) stress on the antioxidant activity of wheat seedlings of different cultivars after 15 d growth with 200 μmol / L CdCl 2. The results showed that the antioxidant enzyme activity of four wheat cultivars was not significantly affected by Cd stress for 4 d, but no significant difference was observed among the four cultivars.At 8 days after Cd stress, 12 was the most severely affected by cadmium stress, with the worst growth, the content of malondialdehyde (MDA) increased obviously and the conductivity increased. The activity of antioxidant enzymes was also affected to some extent. The contents of superoxide dismutase Peroxidase (POD), ascorbate peroxidase (APX) and glutathione peroxidase (GPX) activity were strongly inhibited.In contrast, two cultivars Chuanmai 47 and Xiaoguan 54-2 Under the Cd stress, MDA and conductivity did not change significantly, and maintained a higher absolute water content, and the antioxidant enzyme activities were also enhanced as the Cd stress time lengthened.In addition , All of the four cultivars accumulated more cadmium ions in the roots and less accumulated in the leaves.The order of accumulation of cadmium ions was 12> Chuanmai 42> Chuanmai 47> Xiaoguan 54-2. Therefore, it can be speculated that cadmium absorbed more has an inhibitory effect on antioxidant enzyme activity, thus indicating different cadmium resistance mechanisms of different wheat cultivars .