Study On Screening, Isolation And Identification Of The Glyphosate Methlparathion-degrading Bacterium

Organophosphate pesticides is the most widely used pesticide varieties because of their economic, efficient, easy to use. For the prevention and control pests and ensure food production has played a very important role. China is a large pesticide production country, not only its own requirements for large, but also exported to many countries in southeast Asia. Which has more than 200 kinds of organophosphorus pesticides, production accounting for more than 50% of the total pesticides, about 30% of the world's total.microbes feature fast and easy manipulation, and have many varieties, They are important biological resources of bioremediation. Use of degrading enzymes produced by micro-organisms to deal with environmental degradation of organophosphorus pesticides, have shown a good prospect, is the main development direction about the degradation of organophosphorus pesticides in recent years. Therefore, the purpose of this study is to find out the degradation of organophosphorus pesticides good dominant species, to do some physiological and biochemical analysis and identification. At the same time,to find the optimum conditions of optimizing the degradation of organophosphorus pesticides, finish the preparatory work for in-depth study of preparation of organic phosphorus degrading bacteria.Isolate and identificate the methlparathion-degrading bacteria from activated sludge sample of wastewater treating pond of Sichuan Bei'er pesticide factory. According to a series of mathods, we have high efficient methlparathion-degrading bacteria BR13 and BR57, the degradation rates were 60.20% and 57.67%.Based on the results of morphology, physiological and biochemical properties and phylogenetic analysis of 16S rDNA sequence, strain BR13 was identified as P. Putida, strain BR57 was identified as Morganella sp. Through analyze factors of organophosphorus pesticide impact at bacterail of degradation. BR13 and BR57 on the degradation of organophosphorus pesticide with the genetic stability can be better to degrade glyphosate. though the single factor and orthogonal experiment. the degradation of glyphosate BR13 best combination of sucrose 2.5%,0.1% oxalate ammonium temperature 28℃, shaking speed 180r/min. Degradation of glyphosate BR57 best combination of 1% sucrose,0.1% oxalate ammonium, temperature 30℃, shaking speed 120r/min.