DSP-B菌株的分离、鉴定及其对毒死蜱降解性能研究

Isolation,identification and degradative properties of DSP-B for chlorpyrifos

从成都市龙泉驿区桃园土中分离一株以毒死蜱为唯一碳源的菌株DSP-B,通过生理生化鉴定和16SrDNA序列相似性分析,该菌为克雷伯氏菌属(Klebsiellasp.).DSP-B最适生长温度为35℃,最适pH值为7,最适降解浓度为150mg/L.接入150mg/L毒死蜱基础盐培养基中,35℃,180r/min培养5d,测其降解率为94%.室内试验中,与对照相比,降解菌剂对圣女果和枇杷上毒死蜱的降解能力提高了2.42和4.32倍.大田试验中,降解菌剂对桃子和豇豆上的毒死蜱的最终降解率高达95.65%和96.87%.

A bacterial strain named DSP-B, capable of effectively degrading ehlorpyrifos was isolated from a methidathion-treated orchard. Based on its Physiological-biochemical characteristics test and phylogenetic analysis of 16S rDNA gene, the strain DSP-B was preliminarily identified as Klebsiella sp. The optimal growth temperature, pH and concentration of chlorpyrifos for DSP-B were 37℃, 7 and 150 mg/ L, repectively. Strain DSP-B can degrade chlorpyrifos at a rate of 94% within 5 days under the conditions of 35℃, 180r/rain and 150 mg/L of the initial concentration. Compared with control group, the chlorpyrifos degradation rate of the bacterium on cherry tomatoes and loquat, 2.42 and 4.32 times was improved in laboratory. 95.65% and 96.87% of the chlorpyrifos on the peaches and cowpea were degradated.