| Dioryctria abietella is one of the most important pests that harm cones of Pinus koraiensis in Heilongjiang Province,which leads to the abnormal development of seeds,the rot or yellowing of the damaged parts,and seriously affects the yield of Korean pine cones.It is extremely difficult to control the larva of D.abietella,which lives concealed and has long adult emergence period,in this study,the effects of 8%clothianidin beta-cyhalothrin,3%beta-cypermethrin,6%permethrin fenylurea and 1%avermectin microencapsulated insecticides on protective enzymes and detoxification enzymes of D.abietella were investigated.The residues of thiamethamine and cyhalothrin microcapsules in cones of Pinus koraiensis and the electrophysiological and behavioral responses of adult D.abietella to eight volatile compounds of Pinus koraiensis were detected.These studies were conducted to test the control effect of microcapsules on larvae and the behavioral interference effect of microcapsules on adults.The results show that:（1）Laboratory toxicity test of four microcapsules insecticides against D.abietella.The results showed that the toxicity of the four insecticides was 1%avermectin>8%clothianidin beta-cyhalothrin>6%permethrin fenylurea>3%beta-cypermethrin.（2）Effects of four microencapsulated insecticides on protective enzymes of D.abietella.The response of protective enzymes to insecticides varied with treatment time and concentration.The lethal medium concentration of clothianidin beta-cyhalothrin and various concentrations of avermectin could activate SOD.The high concentration of beta-cyhalothrin showed high concentration activation and low concentration inhibition,while the lethal medium concentration of permethrin fenylurea inhibited SOD activity.High concentration of clothianidin beta-cyhalothrin and low concentration of permethrin fenylurea could activate POD activity,while low concentration of permethrin fenylurea inhibited POD activity.The effects of lethal medium concentration of beta-cypermethrin and sublethal concentration of clothianidin beta-cyhalothrin and avermectin on POD activity were first inhibited and then activated.Each concentration of the four insecticides could activate CAT activity.（3）Effects of four microencapsulated insecticides on detoxification enzymes of D.abietella.The effect of insecticide on detoxification enzyme was also different.GST activity was first activated and then inhibited by two concentrations of clothianidin beta-cyhalothrin and lethal concentration of beta-cypermethrin,low concentration beta-cypermethrin and abamectin and high concentration of permethrin fenylurea inhibited GST activity,POD activity were first inhibited and then activated treated by low concentration permethrin fenylurea,high concentration of abamectin activated GST activity.The activity of Car E was first activated and then inhibited by clothianidin beta-cyhalothrin and beta-cypermethrin at medium lethal concentration and four insecticides at sublethal concentration.The activity of Car E was activated and then inhibited by high concentration of permethrin fenylurea and avermectin,respectively.（4）Residues of 8%clothianidin beta-cyhalothrin microcapsules in Korean pine cones.The insecticidal effect of three concentrations of clothianidin beta-cyhalothrin was the best after 15 days of treatment,and the adjusted mortality was 43.5%,47.4%and 51.2%,respectively.Adjusted mortality increased with increasing treatment time in the 750-fold dilution and 300-fold dilution groups.Most of the insecticides were concentrated in the seed coat and seed scale of Korean pine,which coincided with the habit of feeding only on the seed coat and seed scale of the D.abietella.The residual amounts in Korean pine seeds were 0.0079mg/kg,0.0094 mg/kg and 0.0111 mg/kg,respectively,and those in 750 and 300 dilution groups were significantly lower than the national standard of 0.01mg/kg.（5）The electrophysiological and behavioral responses of adult abies nerbois to eight kinds of volatile microcapsules of Korean pine showed that both male and female adults had EAG response to different concentrations of volatile microcapsules.10-2mol/Lα-pinene,10-1mol/Lβ-pinene,camphene,phellandrene and carene,10-3mol/L dipentene and myrcene,10-4mol/L ocimene induced the strongest EAG reaction in females.The concentrations of 10-1and 10-2mol/Lα-pinene and dipentene,10-1mol/Lβ-pinene and myrcene,and 10-2mol/L ocimene induced the strongest EAG reaction in males.There was no significant difference in the relative EAG response of male D.abietella with different concentrations of camphene,phellandrene and carene.Among the eight volatiles,α-pinene,carene,β-pinene and phellandrene had attractant effect on females,myrcene and ocimene had repellent effect on females,β-pinene,carene and myrcene had attractant effect on males,and dipentene had repellent effect on males.Microcapsule preparation has great application prospect in the prevention and control of D.abietella.According to the above results,the four kinds of microcapsules can induce different degrees of stress response of the fir tip spot boby,andβ-pinene and hydrocyrene of the Korean pine volatiles can attract both male and female adults.To understand the response of protective enzymes and detoxifying enzymes to four kinds of microencapsulated insecticides,pesticide residues,and the optimal concentration of microencapsulated volatile to adult behavior,can provide a theoretical basis for the formulation of control programs and control technical regulations. |
