摘要
为了解Cu、Zn对水蕹菜生长的影响以及Se缓解Cu、Zn胁迫的效果,本试验以大叶水蕹菜和柳叶水蕹菜为材料,通过营养液栽培,研究了Cu、Zn处理下水蕹菜产量、生理指标和Cu、Zn含量的变化以及Se对Cu、Zn胁迫下水蕹菜生长的影响。结果表明:低浓度Cu、Zn促进水蕹菜生长;高浓度Cu、Zn抑制其生长,表现为根系活力、抗氧化酶活性和净光合速率(Pn)下降,MDA含量增加。Cu、Zn浓度分别为4.00和8.00 mg·L^(-1)时,水蕹菜产量显著下降。Cu对水蕹菜的毒害高于Zn,柳叶水蕹菜的抗氧化能力高于大叶水蕹菜。水蕹菜中Cu、Zn含量随处理浓度的增加而增加。SOD、POD、CAT和脯氨酸在缓解低浓度Cu、Zn毒害中具有协同作用。高浓度Cu、Zn处理时,水蕹菜抗氧化酶活性受到抑制,则以植物络合素(PCs)和脯氨酸的抗氧化作用为主。Se能提高水蕹菜、抗氧化酶活性以及PCs和脯氨酸含量,增强水蕹菜对Cu、Zn的抗性,提高根系活力和Pn,降低MDA的积累,促进水蕹菜生长。当水蕹菜受到轻度Cu、Zn毒害时,5.00 mg·L^(-1)的Se处理缓解效果较好。Se浓度过高会加剧Cu、Zn对水蕹菜的毒害。
A hydroponic experiment was carried out to study the influence of Cu and Zn on water spinach growth and the antidotal effect of Se. Physiological indexes, yield, Cu and Zn contents in two water spinach varieties （ wide-leaf and narrow-leaf water spinach）, and the antidotal effect of Se were investigated. The results indicated that low-concentration Cu and Zn accelerated the growth of water spinach, and high-concentration Cu and Zn restrained the growth by decreasing root activity, antioxidative enzyme activities and net photosynthetic rate （P,） and increasing MDA content. The yield of water spinach decreased significantly when Cu concentration was 4.00 mg·L^-1 and Zn concentration was 8.00 mg ·L^-1. Cu was more harmful to water spinach than Zn. The narrow-leaf water spinach had a higher antioxidation ability than the wide-leaf variety. Cu and Zn contents in the two water spinach varieties increased with the increasing concentrations of Cu and Zn in nutritive medium. SOD, POD, CAT and proline played a cooperative role in allevi- ating low-level Cu and Zn toxicity. High-concentration Cu and Zn restrained the antioxidant en- zyme system, while the alleviation was dominated by the non-enzymatic system. Se improved the resistibility of water spinach under Cu and Zn stress, resulting in the decrease of MDA content and increases of proline and phytochelatins （PCs） content, yield, root activity, P, and antioxidant enzyme activity. When water spinach was slightly affected by Cu or Zn, 5.00 mg ·L^-1Se could increase the yield of water spinach and provide Se-enriched production. However, excess Se could exacerbate the toxicity of Cu and Zn.
出处
《生态学杂志》
CAS
CSCD
北大核心
2016年第2期470-477,共8页
Chinese Journal of Ecology
基金
江苏省农业三新工程项目(SXGC[2014]314)资助
作者简介
韩承华，男，1985年生，博士，主要从事农产品安全与环境方面的研究。E—mail：360885829@163．com
通讯作者E-mail：jzjiang@yzu．edu．cn
