镉胁迫对大豆花荚期生理生态的影响

Effects of Cd～(2+) on the physiological and biochemical properties of Glycine max in flowering-poding phase

为了探讨重金属胁迫对大豆繁殖期生理生态的影响,采用盆栽试验方法,研究了Cd2+胁迫对五月王和日本青两个大豆品系花荚期植株生长及叶片叶绿素含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性和丙二醛(MDA)含量的影响。结果表明:(1)低质量分数Cd2+胁迫对2个大豆品系的花荚期植株生物量和植株高度均具有促进作用,但随着Cd2+质量分数的增加转而抑制大豆植株的生物量和高度的增加,且质量分数越高其抑制作用越明显。(2)不同质量分数Cd2+处理对花荚期大豆叶片叶绿素合成具有刺激效应,两个大豆品系结荚期的叶绿素含量随胁迫时间的延长呈先增加后降低的趋势。(3)短时间、低质量分数的Cd2+胁迫能增强大豆花荚期SOD活性,长时间、高质量分数的Cd2+胁迫能抑制大豆花荚期SOD活性。(4)随着Cd2+质量分数增加,五月王和日本青结荚期POD活性逐渐升高,但其时间效应有差异;随着胁迫时间的延长,日本青花荚期POD活性稳步提高,而五月王在长时间、高质量分数Cd2+胁迫下POD活性降低。(5)随着Cd2+质量分数和胁迫时间的递增,大豆MDA含量呈"先升后降"趋势。(6)大豆五月王和日本青花荚期对Cd2+耐受性存在较大差异,这主要是由二者的遗传学因素不同决定的而不是环境因素。

For the sake of discussing the physiological and ecological adaptability changes of soybeans in the spawing period under the intimidate of heavy metal, A pot experiment was conducted to study the effects of different Cd2＋ mass contents on seedling growth and chlorophyll contents, SOD （superoxide dismutase） activities, POD （Peroxidase） activities and MDA （malondialdehyde） contents in leaves of Glycine max （Wu Yue Wang and Ri Ben Qing ） in flowering-poding phase.The results showed as follows： （1）Low mass contents of Cd2＋ boosted the biomass and plant height of the flowering-poding phase Glycine max, but higher mass contents Cd2＋ had restrain domino offect. （2） Different mass contents of Cd2＋ had a stimulate effect on composeing chlorophyll. With the time prolonged the content of chlorophyll increased first and decreased later. （3） Cd2＋ stress with lower concentrantions stimulated SOD activity of Glycine max in flowering-poding phase in a short time, but SOD activity was inhibited under higher Cd2＋ concentrantions in a long time. （4） Along with the increase of the concentration of Cd2＋, the activities of POD of Wu Yue Wang and Ri Bn Qing escalated, but there were differences in the domino offect of the time. With the time prolonged, the activities of POD of Ri Ben Qing increased steadily, Cd2＋ stress with higher mass contents decreased POD activities of Wu Yue Wang in a long time. （5） with the increase of Cd2＋ mass contents and stress time, MAD contents of the two soybeans rises first and fall later. （6）The big difference of the tolerances of the two varietal soybeans was dued primarily to genetics.