| In order to exploit chlorfenapyr to control pests safely and efficiently in mulberry fields, the four formulations of chlorfenapyr were designed, compared the physicochemical characteristics of the different formulations, detected the residual amount in the mulberry and cabbage leaves and the penetration rate on the epidermis of diamondback moth of different formulations of chlorfenapyr by GC, compared the effect of the different formulations of chlorfenapyr to the photosynthetic characteristics and the leaf qualities. The toxicity of chlorfenapyr with different formulations to the silkworm and diamondback moth were determined by the leaf and pest dipping methods, compared the effect of chlorfenapyr with different formulations to the growth of silkworm and also determined the residual toxicity of the chlorfenapyr with different formulations to the silkworm, detected the degradation dynamics of chlorfenapyr and the final residual amount of chlorfenapyr in the mulberry leaves.The results are as follows:1. The 10% chlorfenapyr water emulsion and the 10% chlorfenapyr microemulsion were designed successfully by screening and combining the organic solvent and the surface activating agent et al. And also the 10% suspension concentrate was designed by screening the wetting dispersant, thickening agent and antifreeze with the wet superfine grinding method. Simultaneously, 10% chlorfenapyr emulsifiable concentrate was designed by screening the organic solvent and the emulsifier. By determination and comparison with the same kinds of the formulations, the four formulations of chlorfenapyr were accord with the standard of the nation.2. The results of the physicochemical characteristics of the four formulations show that the surface tension of the four formulations is of the same regularity. The lower the dilution, the smaller the surface tension. On the contrary, the higher the dilution, the greater the surface tension. In the same dilution ratio, the sequences of the surface tension of the four formulations are as follows: 10% chlorfenapyr suspension concentrate>10% chlorfenapyr water emulsion>10% chlorfenapyr emulsifiable concentrate>10% chlorfenapyr microemulsion. The larger the dilution ratio, the bigger the distance of the surface tension between the four formulations of chlorfenapyr. The contact angles of the four formulations are of the same regularity, namely, the lower the dilution ratio, the smaller the contact angle. At the same dilution ratio of the four formulations, the sequences of the four formulations are as follows: 10% chlorfenapyr suspension concentrate>10% chlorfenapyr water emulsion>10% chlorfenapyr emulsifiable concentrate>10% chlorfenapyr microemulsion. The sequences of the distribution area of the four formulations on the wax surface are as follows: 10% chlorfenapyr microemulsion>10% chlorfenapyr emulsifiable concentrate>10% chlorfenapyr water emulsion>10% chlorfenapyr suspension concentrate, the distribution areas are 3.08, 2.60, 2.36 and 1.38 times of the water's. The sequence on the mulberry leaf are as follows: 10% chlorfenapyr microemulsion>10% chlorfenapyr water emulsion>10% chlorfenapyr emulsifiable concentrate>10% chlorfenapyr suspension concentrate.The distribution area of the four formulations are 2.30, 2.28,1.16 and 1.08 times of the water's on the mulberry leaves. And, the distribution areas of the four formulations on the cabbage leaves are as follows: 10% chlorfenapyr microemulsion>10% chlorfenapyr emulsifiable concentrate>10% chlorfenapyr water emulsion>10% chlorfenapyr suspension concentrate and the distribution area are 2.49, 2.25, 1.39, and 1.36 times of the water's.3. After 48h treated with the the four formulations of chlorfenapyr, the residual amount of the pesticides in the mulberry leaves took up 54.6% of the total amount of the chlorfenapyr when treated with the chlorfenapyr microemulsion, and the emulsifiable concentrate, 47.0%, the suspension concentrate, 39.2%, the water emulsion, 37.6%. After 48h treated with the the four formulations of chlorfenapyr, the residual amount of the chlorfenapyr in the cabbage leaves took up 50.2% of the total amont of the chlorfenapyr when treated with the chlorfenapyr microemulsion, and the chlorfenapyr emulsifiable concentrate, 44.4%, the water emulsion, 43.2%, the suspension concentrate, 34%.4. The results show that the net photosynthetic rate, stomatal conductance, transpiration rate and the protein and soluble sugar contents increase in various degrees treated by 4 formulations of chlorfenapyr in mulberry leaves compared to the control. The effects on the net photosynthetic rate are microemulsion > suspension concentrate > emulsifiable concentrate > water emulsion, and the effects of microemulsion on the protein and soluble sugar contents are most significant. The contents of fat decrease slightly in the prior period after treating compared to the control and recovered to the level of the control after 6 days. The intercellular concentration changes of CO2 do not have obvious rules. The results also indicate that there are no adverse effects on the photosynthetic characteristics and quality of mulberry leaves among the 4 formulations of chlorfenapyr. 5. The 2nd instar larvae of silkworm were treaded with chlorfenapyr emulsifiable concentrate, microemulsion, water emulsion, suspension concentrate using food intake method, the LC50 values are 286.23,296.25,313.02 and 329.94 mg·L-1 respectively. The toxicity of the four different chlorfenapyr formulations to 3nd instar larvae of silkworm were determined by pest dipping method, the LC50 values are 548.77,492.98,589.52 and 554.47 mg·L-1 respectively. The 4nd instar larvaes of diamondback moth were treaded with chlorfenapyr suspension concentrate, water emulsion, microemulsion, emulsifiable concentrate using dipping method, the LC50 values are 20.958,12.368,29.402和36.773 mg·L-1 respectively. The LC50 values of the four formulations to the 4nd instar larvaes of diamondback moth are 9.0186,8.2699,20.957 and 10.815 mg·L-1 respectively. The toxicity of different chlorfenapyr formulations to the 4nd instar larvae of diamondback moth determined by leaf dipping method and pests dipping methods have significant difference, and the toxicity that is determined using leaf dipping method is higher, it indicates that the stomach poisoning of chlorfenapyr is more important than contact killing in the aspects of lethal effect of the diamondback moth.6. The 2th instar larvae of trimolter and tetramolter were fed with the mulberry leaves which were treated with 100 mg·L-1 chlorfenapyr with the four formulations, the growth and development of the silkworm were observed. The results show that there is no significant effect on the development duration, body weight of molting silkworm, cocoon weight, cocoon shell weight, pupal weight and pupation rate of the silkworm among the four formualatons of the chlorfenapyr.7. The residual toxicity of chlorfenapyr with different formulations was determined, the results show that the chlorfenapyr with four formulatons at 50mg·L-1 are not harmful to the silkworm all the time and has no significant difference compared with the control. While, when the concentration was increased to 100 mg·L-1, 24h after treated with the four formulations, the silkworms are poisoning and died occasionally. 24h after treated the pesticide, only the chlorfenapyr EC has lethal effect to the silkworm and the other formulations have no effect on the development of the silkworm compared with the control, and there is no poisoning silkworms after 72h treated with the four formulations. When treated with 150 mg·L-1, only chlorfenapyr EC can result in the death of the silkworm after 96h, the other formulations has no effect on the growth of the silkworms and have no significant difference compared with the control. When the chlorfenapyr concentration increased to 200 and 250 mg·L-1, the high concentration can result in the poisoning and death of the silkworms, and the survival is smaller and grow slowly and has significant difference compared with the control.The main poisoning symptoms of the silkworms are antifeedant, inanimation, and hindered growth and development, some serious poisoning silkworm curled into a "S" type, and the individual who poisoned deeper were died. The penetration ability of the chlorfenapyr microemulsion is the most on the epidermis of diamondback moth, the next is the chlorfenapyr suspension concentrate, and the least one is the chlorfenapyr water emulsion. The penetration rate of the chlorfenapyr microemulsion and emulsifiable concentrate is not correlated with the pesticide concentration; while the penetration ability of the chlorfenapyr suspension concentrate and the water emulsion have high correlation with the concentration. When treated with 100 mg·L-1 chlorfenapyr 9 h, the sequences of the penetration ability are as follows: the penetration rate of chlorfenapyr microemulsion is 88.30%, and the chlorfenapyr emulsifiable concentrate, 84.32%, the chlorfenapyr suspension concentrate, 50.76%, the chlorfenapyr water emulsion, 44.55%.8. The degradation kinetics equation and the half life time of different chlorfenapyr formulations in mulberry leaves are as follows: the degradation kinetics equation of chlorfenapyr SC is C = 93.466e-0.1677t (R2 = 0.9238),the half life time is 4.1d. The degradation kinetics equation of chlorfenapyr EW is C = 97.65e-0.234t (R2 = 0.8808), the half life time is 3.0 d, the degradation kinetics equation of chlorfenapyr ME is C = 97.675e-0.2261t (R2 = 0.855), the half life time is 3.1 d. The degradation kinetics equation of chlorfenapyr EC is C =124.85e-0.2287t (R2 = 0.8781), the half life time is 3.0 d. The minimum detectable concentration of this method is 3.97×10-4 mg·kg-1. The mulberry leaves are treated by four different chlorfenapyr formulations at a concentrate of 100 mg·L-1, and the residual levels are detected after 28 d, the results are as follows: the residual levels of chlorfenapyr SC are 0.019 mg·kg-1, the residual levels of chlorfenapyr EW are 0.017 mg·kg-1, the residual levels of chlorfenapyr ME are 0.012 mg·kg-1, the residual levels of chlorfenapyr EC are 0.016 mg·kg-1.9. After the mulberry leaves were treated by four chlorfenapyr formulations at concentraton of 250, 200, 150, 100 and 50 mg·L-1, and the period of residual toxicity is detected. The results are as follows: chlorfenapyr SC, > 5 d, > 5 d, 3 d, 1 d and 0 d, chlorfenapyr ME, > 5 d, > 5 d, 3 d, 1 d and 0 d, chlorfenapyr EW, > 5 d, 4 d, 2d, 1 d and 0 d, chlorfenapyr EC> 5 d, > 5 d, > 5 d, 2 d and 0 d.10. The safety interval of four kinds of 10% chlorfenapyr formulations is 5 days after spraying the chlorfenapyr at 100 mg·L-1, and the safety interval of four kinds of 10% chlorfenapyr formulations is 14 days at 200 mg·L-1. It is recommended to use four kinds of 10% chlorfenapyr formulations to prevent and control the mulberry pests and pest mites at 100 mg·L-1.11. By the comprehensive analysis of the physicochemical characteristics, the poisonous effect , the physiological effect to the mulberry leaves and the residual toxicity of the four formulations of chlorfenapyr, which indicates that chlorfenapyr microemulsion is of high efficiency to pests, high safety to silkworm and could be utilized as the economical and environmental friendly formulation in the mulberry fields.
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