Control Effect And Residue Behavior Of 10% Cyantraniliprole Oil Dispersion In Rice Field

Rice-crayfish co-culture System,which is a igh-efficiency model of the comprehensive rice planting,that is supported and promoted by government,currently.Cyantraniliprole is one of the most important recommended agents for the prevention and control of rice pests.However,the utilization of 10%cyantraniliprole oil dispersion in rice-crayfish co-culture system has not been reported.In this study,the control effect of 10%cyantraniliprole oil dispersion to Cnaphalocrocis medinalis,Chloethrip oryzae,and Chilo suppressalis was evaluated.Residue behaviors of cyantraniliprole in rice-crayfish co-culture system were studied.These results provide a scientific basis for guiding the rational utilization of 10%cyantraniliprole oil dispersion.The main findings are as follows:1.Control effect of 10%cyantraniliprole oil dispersion to Cnaphalocrocis medinalis and Chloethrip oryzae10%cyantraniliprole oil dispersion showed good control effect to Cnaphalocrocis medinalis and Chloethrip oryzae,when the treatment concentration was 40 g·Mu-1.The effect to Cnaphalocrocis medinalis and Chloethrip oryzae was 86.7-92.9%and 83.4-88.7%in the third day after sprayment,respectively.Which was 88.5-94.3%in the fourteenth day and 91.0-93.4%in the twenty-first day,indicating the persistence of 10%cyantraniliprole oil dispersion.2.Comparison of the control effect of 10%cyantraniliprole oil dispersion to the Chilo suppressalis in conventional rice and rice-crayfish co-cultureCyantraniliprole showed good control effect to Chilo suppressalis,and there was no significant difference between different planting model of rice(p<0.05).With the increase of dosage,the rice dead heart rate decreased from 0.18-0.34%to 0.06-0.11%,which was lower than the control agent's 0.21-0.93%.The control effect of Chilo suppressalis in conventional rice was 85.5-95.8%,and the value was 80.7-96.1%in another planting model with 40 g·Mu-13.Analysis method of cyantraniliprole residue on rice plant,rice,rice husk,water and soilIn this study,a analysis method to detecting the residue of cyantraniliprole in rice plant,rice,rice husk,water and soil was established with good precision,sensitivity and accuracy.The linear relationship between cyantraniliprole and the concentration range of 1-1000 ?g·L-1 was good,and the correlation coefficient was more than 0.996.The limit of detection(LOD)and limit of quantification(LOQ)was 0.489-1.320 ?g·kg-1 and 1.132-4.061 ?g·kg-1,respectively.When the spiked concentration was 20,200,and 1000 ?g·kg-1,the average recovery was 77.1-1 19.9%,and the relative standard deviation was 0.02-6.03%in all matrix.All validation parameters were generally acceptable for a survey study of this kind,suggesting that the method was sufficient for analysis4.Residue degradation dynamics and final residue of cyantraniliprole in the rice-crayfish co-culture systemThe residue degradation dynamics of cyantraniliprole in rice plants and water accorded with the first-order kinetic equation,showing a significant degradation trend.The spraying concentration was 30 mL·Mu-1,the R2 of degradation curve about cyantraniliprole in plant and water was 0.9867 and 0.8078,half-life period was 3.8 d and 4.6 d,respectively.In the twenty-eighth day after application,the degradation rate of cyantraniliprole in plant and water was more than 99%.The residue degradation of cyantraniliprole in soil showed a tendency of increasing in the period of 14 days after sprayment,and then decreasing.The residue value was 0.004 mg·kg-1 in the fourteenth day.In addition,the final residue of cyantraniliprole in rice and rice husk was less than the LOQ value.