Evaluation On Deposition And Utilization Of 5 Formulations Imidacloprid On Lycium Barbarum By Spray Adjuvants

Increasing the utilization rate of pesticide deposition and reducing the amount of pesticide are the trend of agrochemical field.Selecting appropriate pesticide formulations and adding spray adjuvants can increase the deposition utilization rate of pesticide on target crops.The spray adjuvants are the substance that can improve the physicochemical properties of liquid and increase the deposition of liquid.There have been many reported,but there are few studies on the effects of different types of spray adjuvants on different formulations of pesticides with the same active ingredient.Therefore,in this experiment,4 types of spray adjuvants,Qiangliyuan,Mairun,Burisi and Mineral oil,respectively surfactant,vegetable oil,organosilicon and mineral oil,were selected and mixed with five formulations of imidacloprid.The physicochemical properties,droplet distribution,deposition,deposition utilization rate of the liquid,and field reduction experiments were studied to find out the optimal combination of different types of spray adjuvants with five formulations of imidacloprid.In order to improve the deposition utilization rate of pesticide,reduce application amounts,increase efficiency,and provide theoretical basis for the comprehensive prevention and control of Bactericera gobica.The research results of this paper are as follows:1.Adding 4 different types of spray adjuvants could decrease the surface tension,contact angle and drying time of 5 formulations of imidacloprid,and decrease with the increase concentration of spray adjuvants.Overall,the reduction effect on surface tension and contact angle:Qiangliyuan>Mineral oil>Burisi>Mairun,and the reduction effect on drying time:Mineral oil>Qiangliyuan>Burisi>Mairun.Among them,Qiangliyuan had a better effect on imidacloprid 5%SL,Mineral oil had a better effect on imidacloprid 70%WG and imidacloprid 5%SL,Mairun and Burisi had relatively poor effects.2.Adding 4 different types of spray adjuvants could increase the expansion diameter and retention amounts of liquid on Lycium barbarum leaves,and most treatments increase with the increase concentration of spray adjuvants.The synergistic effect of Qiangliyuan was the best,followed by Mineral oil,Burisi,and Mairun was the worst.Among them,Qiangliyuan had a better effect on imidacloprid 5%SL and imidacloprid 70%WP,and Mineral oil had a better effect on imidacloprid 5%SL.The Qiangliyuan and Mineral oil with better synergistic effect were selected and mixed with 5 formulations of imidacloprid,and the field test was studied to control B.gobica.On the last 7 and 10 days after spraying,the treatment of Qiangliyuan+ imidacloprid 5%SL and imidacloprid 70%WP had a better control effect on B.gobica.3.Ponceau-G was used as a tracer to found the optimal spray volume in the field of wolfberry,the results showed that with the increase of spray volume,the droplet diameter,coverage,density,deposition and deposition utilization rate also gradually increased.The growth rate of droplet diameter,coverage,density,deposition and deposition utilization rate of pesticide were the highest when the spray volume was 500-600 L·hm-2,and there was no significant difference in the deposition of liquid on the upper,middle and lower parts of the wolfberry plant at 600 L·hm-2.This showed that the distribution of liquid was uniform,so 600 L·hm-2 was selected as the spray volume for the subsequent test.4.Adding most spray adjuvants could increase the droplet diameter,coverage,density,deposition and deposition utilization rate of 5 formulations of imidacloprid on L.barbarum.The combination of Qiangliyuan+imidacloprid 5%SL had better effects on droplet properties,deposition,and deposition utilization rate,with synergies of 70.95%,321.41%,122.56%,42.53%,51.23%.The combination of Buruisi+imidacloprid 70%WP and imidacloprid 350 g·L-1 SC had better effects on droplet properties,deposition,and deposition utilization rate,with synergies of 41.42%,85.77%,199.91%,47.34%,39.94%;45.75%,117.42%,46.75%,15.54%,72.23%.5.Imidacloprid 5%SL was mixed with spray adjuvants,and the indoor toxicity and field reduction tests were studied.The results showed that all spray adjuvants could increase the toxicity of imidacloprid to B.gobica,and Qiangliyuan had the highest effect that was 2.00.The results of field efficacy test showed that imidacloprid 5%SL reducing 20%,30%,and 40%with spray adjuvants had higher control effects on B.gobica than the control treatment.The effect reached the highest in 10 days after spraying.Imidacloprid 5%SL was reduced by 30%,adding Qiangliyuan and Burisi,and the control effect on B.gobica was higher at 1 and 10 days after spraying,but adding Mineral oil,the control effect of B.gobica was lower.