(26(2):158-168)COMPARATIVE STUDY OF SPRAYING AND PAINTING INSECTICIDES AGAINST CITRUS LEAF MINER, PHYLLOCNISTIS CITRELLA (PHYLLOCNISTIDAE, LEPT.)

當柑桔嫩芽吐露時，及吐芽後每隔7至10天，用納乃得(Lannate) 5~10%，24%溶液加水1.4~2.8倍，塗刷樹幹四周，長及其直徑之3~4倍，連行2次或3次塗刷可以防治柑桔潛蛾Phyllocnistis citrolla Stn.，其效果與0.025％~0.05％納乃得溶液撒布法相同。塗刷防治法不致引起柑桔紅蟎之患，不若採用撒布方法防治潛蛾後，尚須另行防治柑桔紅瞞之費事，因此可以達成柑桔嫩枝葉害蟲之綜合防治目的，且無採用愛速靈(Az-odrin)等防治有新芽脫落，新葉不正及生長停止等藥害現象。納乃得與24％萬待得(Vyd-ate)溶液之最低有效防治潛蛾濃度分別為5％與7.5％。 Citrus leaf miner, Phyflocnistis citrefla Stn. (Phyllocnistidae, Lepidoptera), has been considered as the worst insect pest in citrus nursery, particularly occurred on nonfruit bearing and top grafting trees. Seven insecticides including 24% Lannate, 90% Lannate Wp, 24% Vydate L, 20% Gusathion EC, 60% Azodrin 5, 27.4% Bidrin S, and 50% Monitor S. were applied by spraying and painting method to evaluate the effectiveness of the miner control. Spraying Lannate and Vydate at 0.025-0.05% concentrations, or painting on the trunk of young tree at 5.0-10% concentrations had achieved the most effective control. But the spraying method usually caused the outbreak of citrus red mite, Pannonychus citri (McG.) in order that the mite control was required. The proper time of application for insecticide painted must be started at the new bud appearance and then repeated 2 or 3 times with a 7 to 10 days interval. The effective control was usually obtained by painting insecticides on the trunk about 3 to 4 times as long as the trunk diameter. Painting of Azodrin and Bidrin at 10% concentration often induced phytoxicity such as bud drop, young leaf deformation and tree growing retardation. Therefore, the authors would suggest that the minimum effective concentration of Lannate and Vydate for painting are 5% and 7.5% respectively