| Organophosphate pesticides are one kind of agricultural chemicals which have been widely used and are remain widely used. Their environmental chemistry, fate, toxicology have been extensively studied. Soil microorganisms are an important composition of soil ecological system, an important index of soil fertility. The pesticides used in agriculture are mainly in the soil and effect the soil microorganisms. But there is no reports of the long term Organophosphate pesticides contamination on soil microorganisms. More over, In general, the effect of pesticide on soil microbial communities has often been studied by conventional methods based either on cultivation techniques or on metabolic activities. It is well known that more than 90% of the microorganisms existing in nature are refractory to selective enrichment cultures. To overcome these drawbacks, molecular biological techniques especially 16S rDNA analysis are increasingly employed in the analysis of microorganisms in their natural habitats.This article has been studied the soil microbiological ecological effect of long term Organophosphate pesticides contamination. The conventional culture-dependent method and culture-independent 16S rDNA analysis method were used to investigate the nembure of some soil microbial groups and the bacterial community.The release of Organophosphate pesticides to the soil environment will disturb the community structure of soil microorganisms. Some groups were decreased or disappeared, but some groups which can adapted to the contamination have been the dominant groups. The long term adaptation of environmental microorganisms to the contamination will result in the emergence of many kinds of contaminant degrading bacteria. Study of the degrading bacteria diversity in polluted environment can understand better the mechanism of bacteria adapted to the polluted environment. It provides a better insight into the environmental toxicology, bioavailability of the pollutant and the bioremediation potential of the polluted environment.The diversity of organophasphate pesticides degrading bacteria and the convention of the degrading genes in organophasphate pesticides polluted soil confirmed the horizontaltransfer of degrading genes, revealing the molecular mechanism of the adaptation of soil microbial community to the organophasphate pesticides pollution. Study of the molecular basin of the organophasphate pesticides hydrolase gene horizontal transfer, search for the gene sequence which mediate the transfer of organophasphate pesticides hydrolase gene will play a role in the bioremediation of polluted soil.1.Ecological effects of long-term organophasphate pesticides contamination on soil microfloraThe long-term effects of organophosphate pesticides contamination on soil microflora were investigated in the present study. Little difference in total counts of bacteria, actinomycetes and fungi was observed between the contaminated and the non-contaminated soil. Compared with the control there were a slight decrease in total counts of free-living nitrogen-fixer and denitrifying bacteria and a significant increase in those of ammonifying and ammonia-oxidizing and nitrifying_bacteria in the methylparathion contaminated soil. The respiratory intensity of the contaminated soil decreased by 29.93% while ammonification and nitrification increased significantly than that of control soil.2. Extraction and purification of soil microbial total DNAA method of extracting soil total DNA was developed, and it can extract DNA from G+ bacteria. The soil total DNA was extracted from 9 different soils,the DNA yeild was from 3.30ug to 13.41ug. The crude soil DNA was purified by dialysis bag, the recovery rate is 65.34%. The extracted rate in the 9 soils was 60.51%-93.45%. The traget gene could be amplified from the soil which was added 362 target cell/g.dry soil.3. Long term effect of methylparathion contamination on soil microbial communitydiversity and structure.The long-term effects of organophosphate pesticides contaminatio...
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