有机磷农药乐果降解菌株L3的分离鉴定及其性质的初步研究  

Screening,Identification and Characterization of a Dimethoate Degrading Fungus

作　　者：艾涛[1] 王华[1] 温小芳[1] 张世清[1] 黄俊生[1] 

机构地区：[1]中国热带农业科学院环境与植物保护研究所热带作物生物技术国家重点实验室,海南海口571101

出　　处：《农业环境科学学报》2006年第5期1250-1254,共5页Journal of Agro-Environment Science

基　　金：科技部"科技基础性工作和社会公益研究专项"(2004DIB3J073);科技部"国家科技基础条件平台工作"(2004DKA30560)

摘　　要：从常年施用农药乐果的土壤中,通过富集培养和平板稀释法,分离得到一株具有较强降解有机磷农药乐果能力的真菌菌株L3,通过形态观察及真菌的ITS检测,对其进行了鉴定,同时对其性质进行了初步研究。结果表明,该菌株为Aspergillus nomius。是以共代谢方式降解乐果的。在查氏培养基中最高能耐受6 000 mg.L-1的乐果;在28℃、pH6.0的条件下生长较好,120 h对乐果的降解率达29.2%,并且对其他有机磷农药也有较好的降解作用,120 h对乙酰甲胺磷和辛硫磷的降解率分别达65.9%和95.3%,初步确定菌株L3对有机磷农药的降解有一定的广谱性。By using liquid enrichment culture, a fungus strain L3 was isolated and selected from sample which had been polluted by dimethoate for a long time. The strain was idendified as A spergillus nomius on the basis of morphological observing and phylogenetic inference based on ITS sequence and analysis, The strain was able to utilize dimethoate when carbon source coexisted. Strain L3 could endure high concentration of dimethoate. In flask test strain L3 degraded 29.2% of dimethoate （2 000 mg·L^-1） within 120 h, and the maximum tolerance concentration of dimethoate reached 6 000 mg· L^-1. For strain L3, the optimum pH and temperature for the growth and the degradation of dimethoate was 28 ℃, 7.0 respectively. The degradation curve of dimethoate under the action of L3 showed that after a 24 h＇ s lag phase, the degradation entered exponential phase, and the degradation rate reached 29.2%. The growth of strain L3 was restrained in the first 24 h, and in the followed 72 h the growth of strain entered flourish phase, but in the last 24 h entered wane. The two curves, the growth of strain L3 and the degradation of dimethoate by strain L3, were accordant, and in the beginning strain L3 utilized carbon source preferentially. Strain L3 was also able to degrade other organophosphates well such as phoxim and acephate. When the concentration reached 5 000 mg·L^-1, strain L3 could degrade 95.3% phoxim and 65.9% acephate, indicating that the degradability of strain L3 was broad-spectrum.

关 键 词：有机磷农药 降解 曲霉 

分 类 号：X172[环境科学与工程—环境科学]