| The paper comparatively studied on toxicities of 20%Confider SL to the Hippoodamia(Adonia) variegate (Goeze) and feeding behavior in the laboratory,and effects of different formulations of imidacloprid(20% Confider SL,Gaucho 600FS,Admire70%WG) applied in different methods to the Aphis gossypii Glover,the security of natural enemies,the development of cotton and fiber quality.The main results are as follows:1.The contact toxicity of high concentration of 20%Confider SL is high to adults of Hippoodamia(Adonia) variegate(Goeze),and the percentage of eggs hatching and pupae eclosion are significantly reduced.The dose of 0.06g/L is safe to adults.Doses below 0.24g/L showed a little effects to egg hatching and pupae eclosion,the percentage of egg hatching and pupae eclosion are above 70.97%and 70%respectively.2.The treatment of 20%Confider SL significantly decrease the feeding rate of adults,and influence the feeding choice of adults.The feeding rate of adults to the alive treated aphids and flesh dead treated aphids are 21.8%and 11.5%respectively,and the adult doesn't feed the dried dead aphids at all.3.There are very good effects of foliar application of 20%confider SL to Aphis gossypii Glover.The control effects is around 80%～99.63%in dose of 40g/667m~2,and is around 52.84%～91.96%in dose of 15g/667m~2 within 20days.The control effect of foliar application is around 88.46%～99.54%within 10days to Acyrthosiphon gossypii Mordvilko,but the persistent period was short.No positive effects were observed in the treatment of root watering of 20%Confider SL in dose of 40g/667m~2.4.The foliar application of 20%Confider SL showed relative strong killing effects to all development stages of ladybug,the eggs of Chrysopa perla and Aphid Parasitoids.The quantity of ladybug eggs reduced 78-100%in dose of 40g/667m~2 to compare with the control within 3 to 20days,and the quantity of larvae reduced 51%～100%.The quantity of adults reduced above 70%between 7 to 10days.The foliar application of the 40g/667m~2 of 20%Confider SL and thiodan showed negative effect to the egg laying of Chrysopa perla and Aphid Parasitoids,and the quantity reduced 23%～69%and 62.9%,respectively.The treatment of root watering of 20%confider SL is safe to all investigated natural enemies.5.The foliar application of 20%Confider SL displayed positive effects on the cotton growth,budding and boll formation,whereas the lint percentage is relative low.The effect of root watering is unconspicuous. Although,there are different effects to the cotton quality were observed in treatments of 20%confider SL, however the differences are not significant.6.In the condition of the alkaline-saline soil,the effect of foliar application of Admire to aphids is high;the persistent period is about 20 days.There was little inhibition to aphids treated by Gaucho seed dressing at the early stage of cotton growing lasted for a short time.The number of ladybugs decreased significantly in treatments of Admire and thiamethoxam at the early stage of foliar application,and then the number of ladybugs upturned along with the time prolongation.There was no significant improvements were observed to the growth of seeding stage,budding and flowering in treatments of Gaucho 600FS and Admire70%WG,however the effects on boll formation and boll opening are distinct.7.In the condition of general soil with controlled irrigation,the effects of all pesticide treatments to aphids as well as the safety to natural enemies are similar to results obtained in the experiment of the alkaline-saline soil condition.The enhancement on height of cotton plant and leaf numbers were not significant.Effects of Gaucho 600FS plus Admire foliar application and thiamethoxam to cotton yield are significant since the high bolls per plant,the increase of weight of single boll and lint percentage.
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