Spotted wing Drosophila
Drosophila suzukii (Matsumura)
Like other vinegar flies, SWD adults are small (2-3 mm) with rounded abdomens. Males can be identified by the distinct small, black dot present on each wing. Females are harder to identify, but this can be done by examining the ovipositor under magnification and looking for the distinct serration.
SWD is established or has been found in most fruit-growing states and provinces in eastern North America from QC and ON south to NC and west to WI, IL and KY.
Female flies cut a slit and lay eggs in healthy fruit. The adult female SWD can lay hundreds of eggs in her lifetime of two to three weeks. Infested fruit do not show obvious symptoms of infestation at first, with only a small pinprick visible from the egglaying. Eggs hatch in 5-7 days and larval feeding on the flesh leads to discolored regions and eventually to collapse of tissues.
Adults can be monitored using a trap made from a plastic cup containing a drowning solution and baited with one of a variety of attracts and hung in the plant canopy. A combination of yeast and sugar in water is highly attractive to adult SWD. Commercial lures are also available.
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