Sublethal Effects Of Cyantraniliprole And Imidacloprid On Myzus Persicae(Hemiptera:Aphididae)

The green peach aphid,Myzus persicae(Sulzer)(Hemiptera: Aphididae),is an agricultural pest that seriously affects various crops worldwide and causes severe economic losses to agricultural production.The insect has the characteristics of high reproductive rate and short maturation period,due to long-term and heavy use of chemical acaricides,the problems as retard residue,resistance and resurgence were dramatically set off.Therefore,it is imperative to reduce the usage of chemical pesticides.Recent studies have reported that cyantra niliprole has a good control effect on aphids,which belonging to the second generation of new anthranilamide insecticides,of that with the advantages of suction,no cross-resistance and so on.Meanwhile,imidacloprid is an effective chemical agent to pre vent the aphids recommended by Chinese tobacco company,wich has the advantages of the suction,low toxicity,not easy to produce resistance.And its action mechanism on insects is through blocking conduction of the central nervous system after insects contact imidacloprids,which eventualy leads to insects death.In this paper,the effects of sublethal concentrations cyantraniliprole and imidacloprid on aphids were studied,including the feeding behavior,biochemical level and population level.The effects of sublethal concentrations of cyantraniliprole and imidacloprid on the Aphidius gifuensis were also explored Thus to provide a theoretical basis for rational use of chemical agents and coordination of chemical control and biological control.The main results were summarized as follows:1.Toxicity of cyantraniliprole and imidacloprid to female adults of aphis was determined,and sublethal concentrations were obtained.The effects of sublethal concentrations of cyantraniliprole and imidacloprid on the feed ing behavior of aphis were explored by EPG technique.The LC30 of cyantraniliprole and imidacloprid treated with leaf-dip method for 48 h was 4.933 mg/L and 0.541 mg/L,respectively.The EPG technique was used to study the feeding behavior of aphis in sublethal concentrations of cyantraniliprole and imidacloprid.The EPG waveforms recorded for 6 hours showed that after treatment with two sub-lethal concentrations,the proportion of aphis achieving to reach phloem having the feeding activities were reduced,the time expended on reaching the phloem to have feeding activities was elongated.,and the feeding time was significantly shortened.2.The effects of sublethal concentrations of cyantraniliprole and imidacloprid on acetylcholinesterase(AChE),glutathione S-transferase(GSTs)and multifunctional oxidase(MFO)in aphis were detected.The effects of sublethal concentrations on the main enzymes in aphis were studied.The results showed that the activity of AC hE treated with cyantraniliprole was significantly higher than imidacloprid treated and control at 24 h,and the activation rate of AC hE was 148.99%.After treated with sublethal concentration imidacloprid,the activity of AChE reached highest value at 48 h,and its activation rate reached the maximum value of 155.16%.The activity of GSTs treated with cyantraniliprole was significantly higher than imidacloprid treated and control at 16 h,and the activation rate of GSTs was 233.84%.Treated with sublethal concentration imidacloprid,the activity of GSTs reached highest value at 48 h and its activation rate reached a maximum of 78.89% at 16 h.The activity of MFO treated with cyantraniliprole was significantly higher than imidacloprid treated and control at 36 h,and the activation rate of MFO was 34.12%.After treated with sublethal concentration imidacloprid,the activity of MFO reached highest value at 48 h and its activation rate reached a maximum of 87.69% at 24 h.3.The effects of sublethal concentrations of cyantraniliprole and imidacloprid on the life table parameters of aphis were investigated.The effects of sublethal concentrations of cyantraniliprole and imidacloprid on the F1 population of aphis were studied by using the method of two-sex life table.The results showed that the fecundity of the F1 generation was significantly higher than that of the control.After the treatment of imidacloprid with sublethal concentration,the life span,pre-oviposition period and total spawning period were 0.70 days and 5.95 days,respectively,which were significantly longer than that of cyantraniliprole treatment and control.The intrinsic growth rate and the finite rate of increase were 0.4542 and 1.5749,respectively,which were significantly higher than control.The treatment with imidacloprid was 0.3878 and 1.4738,respectively,which were significantly lower than control.The net reproductive rate was 50.75,which was significantly higher than that of imidacloprid(38.45)and control(37.85)after treatment with sublethal concentrations of cyantraniliprole.The mean generation period of sublethal concentrations of cyantraniliprole was 8.65 days,which was significantly lower than that of imidacloprid,but was significantly higher than that of the control.4.The effects of sublethal concentrations of cyantraniliprole and imidacloprid on Aphidius gifuensis were studied.The results showed that the two kinds of insecticide had a negative effect on behavior and growth of Aphidius gifuensis,and the effect of imidacloprid was more significant than cyantranilipro le.