Some of you who took genetics in college probably remember working with fruit flies. I can still remember the odor coming out of the bottle when you opened it to work with your fruit flies. The object was to breed them and get flies with different colored eyes. It was a simple way to see how genetics works.
No, some student didn't let a bottle of fruit flies loose in the wild. But fruit flies are getting a lot of attention, especially among commercial fruit growers this year. And if you have berries, especially bramble-type berries in a home garden or orchard, you may soon have an unpleasant experience with this cousin of the genetics class fruit fly.
It's called the Spotted Wind Drosophila, notes Larry Bledsoe, Purdue university Extension entomologist. First detected in Michigan in September 2010, it's now made its way into a number of other regions, including Indiana.
"For years people didn't have to worry much about spraying raspberries for blackberries," Bledsoe says. "Now that's no longer the case."
What makes this fly particularly troublesome is that it is aggressive. Where its cousin might feed on spoiled fruit, this species attacks berries in the prime of development. The female cuts a slit into healthy fruit and lays eggs. By the time the fruit is ripe, what you may get when you pluck of a berry is a pile of mush with maggots inside! It's not exactly the appetizing image fruit growers want to project.
The adult lives for only about two weeks, but it can lay 300 eggs in that time period.
Control starts with monitoring the pest, Bledsoe says. There are traps available that can help producers get a handle on numbers. One of the best cultural methods of control right now is to harvest fruit in a timely manner, not letting it get overripe. There are insecticides that can knock down the adults.