Effects Of Thermal Fogging Application On The Activity Of Biopesticides And Stability Of Chemical Pesticides

Thermal fogging application technology is an ultra low capacity application technology,and its characterisitics are water-saving,small droplet size,uniform deposition distribution,high efficiency and so on.Thermal fogger has been widely promoted inChina`sagriculture,but the application of the thermal fogging technology in China is not perfect.For the better use of thermal fogging technology,this paper studied a kind of thermal fogging additive which was based on the technology of thermal fogger,and researched the effects of thermal fogging application on biopesticides and chemical pesticides with different boiling points.On the basis of this,we further studied the control effect of thermal fogger against plant diseases and the applicable doses.The main results shows that:1.The thermal fogging additive is mainly composed by the solvent of thermal fogger,emulsifier,dispersant,antifreeze and settlement agent,and the contents were 77%,16%,1.5%,3% and 2.5%,respectively.The surface tension of the additive was 41.64 mN/m,the viscosity was 17 mPa·s,and the flash point was 96 ?.with a good atomization effect when it was added amount of 15%2.Indoors we studied the effects of thermal fogging application techniques on the activity of Trichoderma harzianum and Bacillus subtilis,the results showed that: there would be about 13.4% damage to the bacteria which treated by the thermal fogger.Through the scanning electron microscopy and spore activity test we can know that the treatment of thermal fogging did not cause any changes in cell morphology.3.The effects of thermal fogging application technology on the stability of different decomposition temperature chemicals were determined by using difenoconazole,pyraclostrobin and flusilazole.We used the HPLC to detect the concentration of the agent before and after treatment by the thermal fogger,and the results were shown that the pesticide concentration which treated by the thermal fogger would become the original 1.5 times.There did not affect the stability of the pesticide which treated by the thermal fogger.4.we used the thermal fogger and knapsack sprayer to spraying the 40% famoxadone·cymoxanil SC to control of the tomato late blight in the greenhouse,the field efficacy was 84.22% when the amount of 40% famoxadone·cymoxanil SC was 30 g/mu,which was much better than the field efficacy of manual sprayer,which was 69.94% respectively.5.we used the thermal fogger and knapsack sprayer to spraying the Tranquility 500 SC to control of the tomato gray mould,and the amount of Tranquility 500 SC were 36 g/mu,48 g/mu,60 g/mu,the control effect of the thermal fogging method was 76.67% when the dosage was 36 g/mu,and the control effect of knapsack sprayer method was 77.38% when the dosage was 60 g/mu,and there was no significant difference between the two groups at 5% and 1%.It can be inferred that the use of thermal fogging method to reduce 40% of the amount of the pesticide dosage still achieve better control effect.