除草剂氟磺胺草醚降解菌FB8的分离鉴定与土壤修复

Isolation，identification and soil remediation of fomesafendegrading strain FB8

摘要:

摘要: 【目的】从氟磺胺草醚污染土壤分离高效降解菌株，进行分类学鉴定、降解特性及土壤修复能力初步研究，为氟磺胺草醚污染土壤微生物修复提供新的菌株。【方法】通过形态特征、生理生化特征和16S rRNA 序列分析方法进行菌株鉴定; 通过农药初始浓度、pH 值、温度等环境因素的研究得到菌株的最适生长条件;通过敏感作物和靶标杂草的盆栽生测试验，验证菌株对氟磺胺草醚污染土壤的修复能力。【结果】本试验从黑龙江省长期施用氟磺胺草醚的大豆田地中分离出一株能以氟磺胺草醚为唯一碳源生长的细菌FB8，初步鉴定为假单胞菌属(Pseudomonas)，该菌株在96 h内对500 mg/L氟磺胺草醚的降解率高达86.75%，其最适生长条件为500 mg /L农药初始浓度、初始pH6.0－8.0、35－37℃，该菌株处理30 d能够显著恢复敏感作物玉米和高粱的各项生物量指标，对氟磺胺草醚浓度为5 mg/kg的土壤修复效果明显。【结论】从黑龙江省污染土壤中筛选得到的高效降解氟磺胺草醚的门多萨假单胞菌Pseudomonas mendocina FB8，盆栽生测试验表明该菌株具有很好的土壤修复作用，可为氟磺胺草醚的生物修复研究提供适宜的菌种资源。

Abstract:

Abstract: [Objective］In order to find new strains to degrade fomesafen in contaminated soil，we isolated and identified a high-efficiency degrading bacterium from polluted soil． The degrading characteristics and remediation ability of the strain were also studied．［Methods］Characteristics of morphological，physiological，biochemical and 16S rRNA sequence were applied to identify the strain．The optimum growth conditions were obtained by studying the effect of environmental factors such as fomesafen concentration，primary pH and temperature on the strain． The strains remediation ability to fomesafen-polluted soil was verified by sensitive crop and target weeds bioassay in pot soil．［Results］A high-efficiency degrading strain FB8 that used fomesafen as sole carbon source was isolated from soybean field suffering fomesafen in Heilongjiang province．It was initially identified as a member of the genus Pseudomonas．The strain could degrade 86.75% of 500mg /L fomesafen within 96 h．Its optimal growth conditions were determined as follows: 500mg /L fomesafen，primary pH between 6.0 and 8.0，and at 35 to 37℃. The strain could remedy the sensitive crop maize and sorghum biomass after treating for 30 d for soil contaminated with 5 mg / kg of fomesafen． [Conclusion] A fomesafendegrading strain FB8 was selected from fomesafen-contaminated soil in Heilongjiang Province．The strain was closely related to Pseudomonas mendocina． The strain was a suitable candidate for bioremediation of fomesafen-contaminated soil．