Study On Distinctions Of Pesticides Resistance And Its Physiology Biochemistry In Different Populations Of Cnaphalocrocis Medinalis Guenee In Different Places Of GuangXi

This paper studied resistance to4pesticides(Chlorantraniliprole’Thiamethoxam, Chlorantraniliprole, Flubendiamide, Avermectin) in12different populations of Cnaphalocrocis medinalis Guenee collected from HePu, FangCheng, NanNing, TianDeng, BaiSe, FuSui, YuLin, GuiGang, HengXian, LaiBin, YongFu, XingAn in Guangxi Province From2010to2012. In addition, The seasonal and Interannual changes of4pesticides resistance were studied in Nanning, LaiBin, HengXian in Guangxi Province.And preliminary explored the relationship between activities of AChE,MFO,EST,GSTs and Cellulolytic Enzymes and resistance to4pesticides of Cnaphalocrocis medinalis Guenee.These were provideded the foundation for4pesticides resistance risk assessment and its mechanisms in Cnaphalocrocis medinalis Guenee, it also laid the basis for scientific and rational using molluscicide.The main results were shown as follows:1.The virulence of the4kinds of insecticides on the Cnaphalocrocis medinalis Guenee.The stomach poisons methods, toxicity of4insecticides in different regions of Guangxi Cnaphalocrocis medinalis Guenee populations were determined. The results show that, the virulence of4Pesticides on Cnaphalocrocis medinalis Guenee two instar larvae were: avermectin LC50:0.0325mg/L)> flubendiamide LC50:0.0493mg/L)> chlorantraniliprole (LC50:0.0589mg/L)> chlorantraniliprole thiamethoxam (L50:0.2107mg/L).2. The resistance monitoring of Cnaphalocrocis medinalis Guenee.Result of monitoring of different regions of Guangxi Cnaphalocrocis medinalis Guenee resistance level to the4pesticides showed that there was existed certain difference. For chlorantraniliprole thiamethoxam,2011, population, the highest sensitivity,LC50 0.0498mg/L, in2012the lowest sensitivity Guigang area population, LC50was0.4928mg/L, the relative ratio of9.90times; to chlorantraniliprole, population in2010guest area the highest sensitivity, LC50is0.0262mg/L, in2012Yulin area population was lowest, LC50is0.2409mg/L, the relative ratio of9.19times; for Flubendiamide, population in2010guest area the highest sensitivity, LC50is0.0134mg/L, in2012Yulin area population was lowest, LC50for0.2110mg/L, the relative ratio of15.75times; for avermectin, population in Fusui area in2010the highest sensitivity, LC50value is0.0112mg/L in2012, the lowest sensitivity Guigang area population, the LC50value is0.1094mg/L, the relative ratio reached9.77times.3. Seasonal and interannual changes of sensitivities of Cnaphalocrocis medinalis Guenee to4pesticides.In both halves of2012, the author had tested the sensitivity of4medicaments for population respectively in Laibin, Nanning, Hepu county. The result shows all the height of sensitivity of Chlorantraniliprole and other4pesticides is same, that is, sensitivity in the first half year is higher than in the second half year, and resistance to pesticides in the first half year improves in different degree comparing with that in the second half year. In Laibin, resistance of population to Flubendiamide improves most fastly. In the last half year, LC50value increases by152.61%comparing to that of the first half year. Resistance of population to Flubendiamide in Heng County changes most slowly, and LC50value of the last half year increases by8.71%comparing to that of the first half year.From2010to2012, the level of resistance to4pesticides of Cnaphalocrocis medinalis Guenee ranks increasingly interannually. The growth in different areas is different, but the growth of resistance is slow. Comparing with the year of2011, the growth of resistance level of population of cnaphalocrocis medinalis guenee to Chlorantraniliprole.Thiamethoxam varies from17.00%to100.02%in Guangxi in2012and to Chlorantraniliprole from25.13%to147.61%, to Flubendiamide from45.86%to224.31%, to Avermectin from18.75%to60.25%.From the results of monitoring of resistance in2010-2012display, the average annual increase rate of the resistance of Cnaphalocrocis medinalis Guenee population to the Chlorantraniliprole.Thiamethoxam is90.69%in LaiBin, and Hepu’s average annual increase rate is43.51%, and Nanning’s average annual increase rate is41.34%. The resistance to the Chlorantraniliprole, the average annual increase rate is101.61%in LaiBin, and Hepu’s average annual increase rate is38.29%, Nanning’s average annual increase rate is52.56%; The resistance to Flubendiamide in LaiBin, the average annual increase rate is127.12%, and Hepu’s average annual increase rate is109.96%, and Nanning’s average annual increase rate is77.61%; The resistance to Avermectin, the average annual increase rate is103.17%in LaiBin, and Hepu’s the average annual increase rate is42.94%, and Nanning’s average annual increase rate is54%.4. The physiological and biochemical mechanism of resistance of the Cnaphalocrocis medinalis Guenee population.In2011, the author tested the AChE activity, MFO activity, EST activity, GSTs activity of Cnaphalocrocis medinalis Guenee in He Pu and another five areas. The result shows the activity of4kinds of enzyme in Cnaphalocrocis medinalis Guenee population is different, and there exists some relation between enzymic activity and resistance of Cnaphalocrocis medinalis Guenee. Among them, the value of LC50of Chlorantraniliprole.Thiamethoxam and AChE activity manifest positive correlation with0.9056as its correlation index, reaching an obvious and significant level; besides, the value of LC50of Chlorantraniliprole and Flubendiamide and EST activity manifest positive relation correlation too, with0.9253and0.9012as their correlation index respectively, all achieving an apparent and important level; however, GSTs activity and MFO activity share a low correlation with the value of LC50of the four drugs, without achieving remarkable correlation.