| 林欣,王立立,杨平,李取生,徐智敏,魏佳,周婷.一株溶磷菌对盐地碱蓬修复盐渍土Cd污染的促进效应[J].农业环境科学学报,2018,37(5):883-891. |
| 一株溶磷菌对盐地碱蓬修复盐渍土Cd污染的促进效应 |
| The promoting effect of phosphorus-solubilizing bacteria on remediation of cadmium-contaminated saline soil by Suaeda salsa |
| 投稿时间：2018-01-15 |
| DOI：10.11654/jaes.2018-0087 |
| 中文关键词: 溶磷菌 盐地碱蓬 根系分泌物 盐渍地 Cd 修复 |
| 英文关键词: phosphorus-solubilizing bacteria Suaeda salsa root exudates saline soil Cd remediation |
| 基金项目:国家自然科学基金项目（41673094）；广东省科技计划项目（2016A020221015） |
|
| 摘要点击次数: 1877 |
| 全文下载次数: 2516 |
| 中文摘要: |
| 为提高盐渍土Cd污染植物修复效率，探讨溶磷菌对盐地碱蓬生长和镉提取效果的影响，采用浸根法收集水培（含2% NaCl）盐地碱蓬的根系分泌物，将其作为唯一碳源培养5株具有Cd活化能力的溶磷菌并依据细菌OD值绘制生长曲线。挑选繁殖速度较快且溶磷和活化Cd能力显著性强（P<0.05）的大肠埃希菌（Escherichia）在3个NaCl浓度（0.3、6、12 g·L-1）处理下，采用摇瓶实验研究该条件下大肠埃希菌对Ca3（PO4）2和CdCO3的溶解效应及代谢产物变化。进一步采用Cd平均含量为1.37 mg·kg-1的污灌菜园土，在3个外源NaCl浓度（0、4、8 g·kg-1）处理下，利用盆栽实验研究大肠埃希菌对盐地碱蓬修复盐渍土Cd污染的促进效应。结果显示：随盐分增加（0.3、6、12 g·L-1），菌株平均绝对溶磷量（扣除不接菌对照值）分别为80.19、78.79、77.54 mg·L-1，平均绝对活化Cd量依次为17.84、17.30、19.73 mg·L-1，说明盐分的增加没有阻碍菌株的溶磷功能，且随盐分的增强，可促进Cd的活化。不同盐分下菌株的代谢物组成有明显变化，0.3、6、12 g·L-1盐分处理下菌株分泌的有机酸分别为5、10、13种，分泌的氨基酸分别为4、8、8种。其中缬氨酸的量随盐分增加显著增加（P<0.05）。盆栽实验中，4 g·kg-1盐分胁迫下，接菌处理的生物量和根际土壤溶液Cd含量较不接菌对照显著增加（P<0.05），Cd总活化量平均增加3.17倍，全量和DTPA提取态Cd富集系数平均提高260%。综上，盐分胁迫下大肠埃希菌可正常生长并促进盐地碱蓬Cd富集。 |
| 英文摘要: |
| In order to improve the efficiency of phytoremediation on cadmium-contaminated saline soil and to explore the effect of phosphorus-solubilizing bacteria on plant growth and cadmium uptake in contaminated soil, root exudates of Suaeda salsa were collected from a sterile hydroponic(with 2% NaCl) culture. Five cadmium-and phosphorus-solubilizing isolates were cultivated using the exudates as a unique carbon source in medium. Their growth curves were obtained by determining their OD values. Escherichia grew faster and had stronger cadmium-and phosphorus-solubilizing abilities than the rest of the isolates(P<0.05). Herein, its changes in ability to solubilize P and Cd from Ca3(PO4)2 and CdCO3, respectively, and in its metabolic products in three concentrations of NaCl medium(0.3, 6, 12 g·L-1) were studied using a shaking flask experiment. A pot experiment was also conducted in sewage-irrigated garden soil(1.37 mg·kg-1 Cd) pretreated with three concentrations of NaCl(0, 4, 8 g·kg-1). The promoting effect of Escherichia on remediation of cadmium-contaminated saline soil by Suaeda salsa was investigated. The results showed that Escherichia produced 80.19, 78.79 mg·L-1, and 77.54 mg·L-1 dissolved phosphorus and 17.84, 17.30 mg·L-1, and 19.73 mg·L-1 dissolved cadmium, respectively, with the 0.3, 6 g·L-1, and 12 g·L-1 salt concentration treatments. This shows that an increasing concentration of salt had no effect on P release and promoted Cd release. There was obvious change in the composition of metabolites of Escherichia under the different salt treatments. With the 0.3, 6 g·L-1, and 12 g·L-1 salt treatments, 5, 10 kinds, and 13 kinds of organic acids and 4, 8 kinds, and 8 kinds of amino acids were released, respectively. The valine content increased significantly with increasing salt(P<0.05). In the pot experiment, biomass and Cd content in the rhizosphere soil solution of Suaeda salsa with bacterial inoculation treatment increased significantly compared with the control(P<0.05), with 4 g·kg-1 salt treatment. The total mobilized Cd in the rhizosphere soil increased by 3.17-fold. The average enrichment coefficient of the total and DTPA-extractable Cd increased by 260%. These results suggest that Escherichia grew normally and promoted the accumulation of Cd in Suaeda salsa under salt stress. This study provides some useful information regarding remediation of cadmium-contaminated saline soil. |
| HTML
查看全文
查看/发表评论 下载PDF阅读器 |
|
|
|
