Methylopila sp. SD-1与大豆联合修复苯磺隆污染土壤

One highly efficient tribenuron methyl-degrading strain, named SD-1, was isolated. According to the phenotypic, physiological and biochemical characteristics, combined with 16S rRNA gene sequence analysis, the strain SD-1 was identified as Methylopila sp. SD-1, which was the first reported strain in the genus of Methylopila that could degrade tribenuron methyl. The strain SD-1 completely degraded 50mg/L of tribenuron methyl in 4d. The optimum temperature and pH were 30℃ and 7.0, respectively. The toxicity of the intermediate from the degradation of tribenuron methyl to soybean growth was significantly reduced. Soybean root exudates proved to promote the growth of strain SD-1, the number of strain SD-1increased from 1.0×10⁷CFU/mL to 6.7×10⁷CFU/mL after 5d. Root exudates contained 16 kinds of amino acids, and the strain SD-1 showed chemotaxis response towards Asp, Glu and Phe in root exudates. The suspension of strain SD-1 was inoculated and the soybean was planted in the soil polluted by tribenuron methyl (3mg/kg). After 4days, strain SD-1 colonized on the root of soybean depending on chemotaxis, and the survival rate of SD-1 was increased. Compared with the treatments that didn't plant soybean, the degradation rates of tribenuron methyl by strain SD-1 in the soybean rhizosphere soil were increased by 36.0%.