Abstract:

We reported in this paper the results of our test of four insecticides used through cover spray for controlling the Asian longhorned beetle, Anoplophora glabripennis (Motsch.). The four insecticides were ASTRO (A. I. 36.8% permethrin) by FMC Corp., AllPro DURSBAN 4E (A. I. 44.9% chlorpyrifos) by Sureco Inc., ORTHENE 75 S (A.I.75% acephate) by VALENT USA Corp., and SEVINXLR PLUS (A. I.44.1% carbaryl) by Rhone_Poulenc AG Co. (now part of Bayer CropScience). The insecticides were sprayed onto 1.5 years old poplar (Populus sp.) trees until insecticide run-off from twigs. Twigs were collected from treated trees once every 3 d until the 21^st day after insecticide application to feed caged adult beetles. Adult mortality was recorded once every day for 3 d. Leaf and twig samples of treated poplar were collected from each treatment 3, 6, 9, 20, 40 d after spray to determine the levels of insecticides in these parts of trees. Although all insecticides showed promise for short term efficacy (>95% 3 d mortality for adults feed on twigs collected 1 after application), permethrin (concentration 920 mg·kg^-1) was the best among the 4 tested insecticides for longer residual activity with 3 d cumulative mortality>95% for adults feed on twigs collected within 15 days after application. Chlorpyrifos (2 245 mg·kg^-1) was the least effective with 3 d cumulative mortality around 60% for adults feed on twigs collected within 6 d after application, while the mortality was around 90% and 75% for acephate (7 500 mg·kg^-1) and carbaryl (17 640 mg·kg^-1), respectively. However, high concentrations of acephate and carbaryl are not feasible for controlling adult beetles, especially in urban areas. In general, levels of insecticides were higher in leaves than in twigs for the 4 insecticide. Levels in leaf 3～9 d after application was 0.9～4.1 mg·kg^-1 for permethrin,2.5～1.6mg·kg^-1 for chlorpyrifos,2.6～2.3 mg·kg^-1 for acephate, and 35.2 ～49.6mg·kg^-1 for carbaryl. Residual levels 20～40 d after application were 2.8～1.9 mg·kg^-1 ,1.4～1.2 mg·kg^-1 , 1.9～1.4 mg·kg^-1 and 40.9～39.7 mg·kg^-1 for permethrin, chlorprrifos, acephate, and carbaryl. Based on the relationship of the mortality of adult beetles and residual levels of insecticides, mortality may reach 95% when the level of permethrin reaches 4 mg·kg^-1 in leaf, 1.4mg·kg^-1 in twig. For acephate, a level of 2.5 mg·kg^-1 in leaves or 2.1mg·kg^-1 in twigs will achieve 90% mortality of adult beetles.

Key words: cover spray, ASTRO^?, AllPro DURSBAN 4 E, Orthene 75 S, SEVIN XLR PLUS, Anoplophora glabripennis (Motsch.)