摘要
从陕西省关中地区的农田及菜园土壤中分离筛选出23株能够以2,4-D为惟一碳源的细菌。采用以2,4-D为惟一碳源的无机盐培养液,在30℃及180r·min-1的恒温摇床中对不同菌株进行培养,通过测定培养12h后培养液中剩余的2,4-D浓度,计算不同菌株对2,4-D的表观降解率。结果表明,菌株SX09、SX13、SX15和SX21对2,4-D初始浓度为0.5g·L-1时的降解率分别达到40.93%、38.00%、35.47%和39.02%。降解特性试验表明,选择2,4-D浓度分别为0.14、0.50、1.40和3.00g·L-1条件下,4株细菌降解2,4-D的最适浓度为0.50g·L-1。4株细菌利用2,4-D生长的最适温度为35℃。菌株SX09、SX13和SX21的最适生长pH值在7.0～8.5之间,而菌株SX15最适生长pH值为7.0。
Soil contamination is a big problem around the world. Nowadays the farm and vegetable soils are seriously contaminated by 2, 4- dichlorophenoxyacetic acid （2, 4-D）, which is extensively used in agriculture as herbicides. This paper focused on the enrichment, isolation and degradation characteristics of 2, 4-D degradation bacteria. 2, 4-D used as a sole source of carbon in the cultural medium, 23 degradation bacteria were isolated and screened from the farm and vegetable soil samples in Guanzhong district, Shaanxi province. After shaking at 30 ℃ and at 180 r·min^-1 for 12 h on the inorganic salt liquid medium in which 2, 4-D was used as a sole source of carbon, the apparent degrading rates of the 4 selected strains SX09, SX13, SX15 and SX21 were 40.93%, 38.00%, 35.47% and 39.02% respectively. The optimum concentration of 2, 4-D for the 4 bacteria was 0.50 g·L^-1. Based on the test in shaking flasks, the 4 strains can grow best at 35 ℃. The optimum pH for strains SX09, SX13 and SX21 was 7.0-8.5, and the optimum pH for strain SX15 was 7.0. This study will provide the ascendant strains for the biodegradation of 2, 4-D.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2007年第6期2183-2188,共6页
Journal of Agro-Environment Science
基金
西北农林科技大学优秀回国人员科研启动资助项目(08080104)
西北农林科技大学大学生科技创新基金(2005)
关键词
2
4-D
土壤污染
微生物降解
2,4-dichlorophenoxyacetic acid
soil contamination
microbial degradation
作者简介
卫亚红（1973—），女，讲师，主要从事环境微生物学方面的研究。E-mail：yahongwei@nwsuaf．edu．cn
