MODIFIED SUMMER PROGRAM USING BORDER SPRAYS FOR MANAGING CODLING MOTH, CYDIA-POMONELLA (L) AND APPLE MAGGOT, RHAGOLETIS-POMONELLA (WALSH) IN ONTARIO APPLE ORCHARDS

The efficacy of two insecticide control programmes for managing codlin g moth, Cydia pomonella, and apple maggot, Rhagoletis pomonella, were compared in commercial apple orchards in Norfolk County, Ontario, Cana da, during the 1993 and 1994 growing seasons. In the cover spray progr amme, sprays of organophosphorous (OP) insecticide for codling moth an d apple maggot control were applied to the entire orchard following On tario integrated pest management guidelines for apple. In the border s pray programme, an initial cover spray of OP insecticide was applied t o the entire orchard to eradicate any codling moths that had colonized the orchard during the previous growing season, and subsequent sprays were applied only to a c. four-tree-wide (i.e. c. 20 m) zone around t he perimeter of the orchard. The border sprays were applied to control codling moths or apple maggots that invaded the orchard since applica tion of the initial cover spray. The border spray programme provided c ontrol of codling moth and apple maggot similar to that obtained using the cover spray programme with no significant increase in other pest damage. One benefit of using the border spray programme would be a red uction in the cost of controlling codling moth and apple maggot. Anoth er benefit of using this programme might be an increase in the natural control of other orchard pests like leafminers, aphids and mites. A b order spray programme should only be used in orchards where codling mo th and apple maggot have previously been reduced to non-detectable lev els and border sprays should be replaced with cover sprays when fruit infested with either of these pests is detected during routine monitor ing in the orchard. Copyright (C) 1996 Elsevier Science Ltd.