Cold Black Fomesafen Residual Dynamics And The Impact On Soil Microbial Communities

Fomesafen, belongs to a kind of diphenyl ether herbicide, the field of soybean,peanut seedling after weeding with high selectivity. For the large area planting soybeanin Heilongjiang province, sulfanilamide grass ether as a kind of commonly usedherbicide between farmers is also widely used. If you use the dosage is too large, orimproper operation, and is likely to plants and crop, after even important impact on soilquality, etc. Soil microbes and enzymes that are involved in the metabolic process ofmaterial in the soil, to a large extent, also can be used as a reference standard ofassessment of soil quality. In this topic, the choice of the black soil of Heilongjiangprovince as the experimental field, farmland in continuous cropping soybean fieldsaccording to the standard two years recommended concentration spraying fluorinesulfanilamide grass ethers, and collecting soil, the traditional microbial test method,and combined with high performance liquid chromatography (HPLC) and gaschromatography mass spectrometry (GC-MS) techniques, evaluated the sulfanilamidegrass ether in the recommended doses, residue in the soil, and the effects on soilmicrobial community and related enzymes, aims at providing a reasonable evaluationof sulfanilamide grass ether field using the provided theoretical basis for reference. Themain results were as follows:（1）Using the HPLC determination for two years use sulfanilamide grass etherresidue and residual dynamic half-life in soybean field. In2012, sulfanilamide grassether in the field of residual half-life of58.2d,2013sulfanilamide grass ether in thefield of residual half-life of30.8d.（2）The determination of fluorine sulfanilamide grass on the soil urease,invertase and catalase, acid phosphatase activity, and changes in the number of bacteria,fungi and actinomycetes in the soil. Are characterized by high residual inhibition, lowresidue on the change trend, shows that soil microbial quantity change has very close connection with the changes of enzyme activity.（3）Through the sulfanilamide grass ether was determined by GC-MS on thecontent of total PLFA, fungi in soil bacteria and designed the GN/GP, the influence ofthe pressure index of these four indexes. Results show that during the two years ofapplying pesticide in soil fungi/bacteria, pressure index, the two indicators have had animpact. Effect on the content of total PLFA and designed the GN/GP significantly, thusit is concluded that because of sulfanilamide grass ether into the change of the soilmicrobial community structure, reduces the stability of soil microbial ecology.