[Cooperative Protection of American Ginseng Seedlings by Applying Imidacloprid, Fludioxonil and Phoxim].

Objective: To screen out an effective method of controlling pests on American ginseng( Panax quinquefolium). Methods: The germinating seeds of the plant from two growers in Liuba County,Shaanxi Province,were collected and potted in pest-residing sandy soils indoors. Four pesticides( imidacloprid wettable powders,fludioxonil flowable concentrate for seed coating,chlorpyrifos granules and pyrifos·phoxim granules) in different modes and doses were applied,and their effects were assayed. Results: Pests were largely enchytraeid( Enchytraeus bulbosus),root mite( Rhizoglyphus robini) and two root rot fungi( Cylindrocarpon destructans and Phytophthora cactorum),which could be transmitted by both seed and soil. The treatment of dressing or soaking seeds in mixed solution of imidacloprid 25 WP and fludioxonil 2. 5SD plus blending the pest-residing sandy soil with chlorpyrifos · phoxim 5G displayed significant effects of both controlling pests and keeping stand of seedlings( P 0. 05); whereas each of the three pesticides exhibited a middle-class effect when applied alone,and chlorpyrifos 10 G showed little effect when applied singly. Conclusion: The combined approach of seedand soil-treatments is able to efficiently reduce damages caused by seed- and soil-born pests,and become one optimal measure protecting seedlings,and is thus suggested to demonstrate and extend in the pests' infestation areas.