铜、锌污染对水稻土中油菜（Brassica chinensis L.）生长的影响及累积效应研究

通过盆栽试验,系统研究了Cu、Zn重金属污染对油菜（Brassica chinensis L.）生长、SOD保护酶活性、脯氨酸、可溶性糖及Cu、Zn在油菜体内吸收富集的影响。结果表明：Cu、Zn污染对油菜生物量和生理生化指标（SOD保护酶活性、脯氨酸和可溶性糖）均有影响。随着Cu、Zn质量分数的升高,植株干物重和SOD保护酶活性表现为先增后降;当Cu质量分数达到1 000 mg？kg-1时,油菜干物重和SOD酶活性分别比对照下降36.79%、66.67%;当Zn质量分数达到3 000 mg？kg-1时,油菜干物重和SOD酶活性分别比对照下降55.21%、82.05%。Cu污染下,油菜叶片脯氨酸质量分数逐渐下降,总可溶性糖质量分数表现为先增后降;Zn污染下,脯氨酸和总可溶性糖质量分数均表现为先增后降。Cu、Zn污染使油菜幼苗叶片及根中的Cu、Zn质量分数明显增加,根部的积累尤其明显。当Cu处理为1 000 mg？kg-1时,油菜茎叶和根中质量分数分别为57.6、424.162 mg？kg-1;当Zn处理为1 000 mg？kg-1时,油菜茎叶和根中质量分数分别为240、608.54 mg？kg-1。与Zn相比,Cu主要积累在油菜的根部,向茎叶迁移累积的量很少,并且随着添加质量分数的增加,茎叶吸收Cu的量变化不大。总之,重金属Zn相对于Cu更容易积累于油菜的地上部分,从而更易进入食物链,它们在油菜体内富集都对其生理生化和营养产生了明显毒害作用。

Impacts of Cu and Zn pollution on rape(Brassica chinensis L.) growth and its accumulation effect of heavy metals in paddy soil

Effects of Cu and Zn on growth,activity of SOD,proline,soluble sugar of rape（Brassica chinensis L.） and its accumulation characteristics of heavy metals were studied by cultivation experiments.The results showed that biomasses、physiological and biochemical index and SOD activity were impacted by Cu,Zn treatments.Dry weight of rape and SOD activity increased with low Cu,Zn concentration treatment.With increasing Cu,Zn concentration,the plant growth slowed down,the biomass and SOD activity decreased.When the concentration of Cu reached 1000 mg？kg-1,dry weight of rape and SOD activity decreased by 36.79%,66.67% compared with the control,respectively.When the concentration of Zu reached 3000 mg？kg-1,dry weight of rape and SOD activity decreased by 55.21%,82.05% compared with the control,respectively.When treated with Cu,the content of proline decreased gradually,the content of soluble sugar firstly increased and then decreased;when the concentration of Cu reached 1000 mg？kg-1,the contents of proline and soluble sugar decreased by 56.55%,37.66% compared with the control,respectively.Under Zn pollution,the contents of proline and soluble sugar increased firstly and then decreased similarly.When the concentration of Zn reached 3000 mg？kg-1,the contents of proline and soluble sugar decreased by 36.32%,36.55% compared with the control,respectively.Treated by Cu and Zn,the Cu,Zn content of leaves and root increased obviously,furthermore,the accumulation of heavy metals in root was particularly obvious.When the concentration of Cu and Zn was 1000 mg？kg-1,the content of Cu in shoot and root were 57.6 mg？kg-1 and 424.162 mg？kg-1,respectively;the content of Zn in shoot and root were 240 mg？kg-1 and 608.54 mg？kg-1,respectively.Contrast to Zn,Cu mainly accumulated in the root of rape.The results indicated that Zn more easily accumulated in the aboveground part of rape,and entered the food chain,compared to Cu.The experiments showed that physiology,biochemistry and nourishment of rape were affected by the accumulation of Cu and Zn obviously.