Indoor toxicity test and field efficacy of six insecticides against the larva of Contarinia maculipennis Felt

ObjectiveDesirable insecticides were studied and screened to provide references for chemical control of C. maculipennis. MethodDipping method and field foliar spraying using were employed to test the indoor toxicity and field efficacy of six high-efficient and low-toxic insecticides against larvae of C. maculipennis. ResultToxicity deter-mination results showed that LC50 order of the insecticides against the larvae was 5% acetamiprid EC<3% avermectins EW<6% spinetoram SC<4.5% beta cypermethrin EC<10% imidacloprid WP<48% chlorpyrifos EC, and the toxicity in-dex was 5% acetamiprid EC>3% avermectins EW>6% spinetoram SC>4.5% beta cypermethrin EC>10% imidacloprid WP>48% chlorpyrifos EC. The results of field experiment demonstrated that 5% acetamiprid EC exhibited the best con-trol efficiency with 78.52% control efficiency, followed by 6% spinetoram SC and 3% avermectins EW, with 68.09%and 60.99% control efficiency to against C. maculipennis after three days of spraying. After seven days of spraying, the highest control efficiency to C. maculipennis was also observed on 5% acetamiprid EC, with 72.12% control efficiency and it was declined to 60.83% and 50.88% when 6% spinetoram SC and 3% avermectins EW were used. ConclusionAcetamiprid should be firstly selected and used in interval rotation with chlorpyrifos and spinetoram for effective control of C. maculipennis.