A Raspberry’s Worst Nightmare

fruit_fly3

With all the beautiful berries available now, I’ve been seeing more fruit flies hanging around the kitchen. Annoying? Yes. Ruining my strawberries? Nope. Fruit flies lay their eggs on damaged or rotting fruit. So they’re only interested in the pieces that are going bad. I’m ok with that.

But consider a fruit fly who lays her eggs on fresh fruit. She’d have the agricultural community freaking out. Just imagine the risk to berry crops. Actually, you don’t have to imagine because scientists have already done the calculations for you: it’s potentially $2.6 billion of risk (1).

Evolution has already dealt this stunning set of cards to Drosophila suzukii, the spotted-wing drosophila (2). The females have an ovipositor (the anatomical structure that deposits eggs) that looks like a serrated knife. Unlike the common fruit fly in your house, this species’ egg-laying parts can cut through the skins of raspberries, strawberries, blueberries, cherries, and grapes.

Want to learn more about the spotted-wing drosophila? IFAS at the University of Florida has a great info page on the little beastie (with horrifically gorgeous pictures, by Martin Hauser, of that ovipositor – if you haven’t seen fruit fly genitalia yet, you are missing out).

p.s. Thanks to Dr. Nadia Singh for introducing me to Drosophila suzukii.

  1. Walsh, Douglas, M. Bolda, R. Goodhue, A. Dreves, J. Lee, D. Bruck, V. Walton, S. O’Neal, F. Zalom. 2011. Drosophila suzukii (Diptera: Drosophilidae): Invasive Pest of Ripening Soft Fruit Expanding its Geographic Range and Damage Potential. Journal of Integrated Pest Management. 2(1): G1-7.
  1. Atallah, L. Teixeira, R. Salazar, G. Zaragoza, A. Kopp. 2014. The making of a pest: the evolution of a fruit-penetrating ovipositor in Drosophila suzukii and related species. Proceedings of the Royal Society B: Biological Sciences, 281 (1781)

Mocking Berries

strawberry

My yard is full of Strawberries – crawling across the patio, creeping over the lawn, growing around the a/c unit. Too bad they’re all fakers.

Delicious Wild Strawberries bloom white flowers that develop drooping mini-versions of the strawberries we know and love. The Mock Strawberries (Potentilla indica) growing in my yard, in comparison, display yellow flowers and upright little red fruits so tempting to behold. It’s like the little plant begs, “Look at this beautiful, juicy berry. Don’t you want to eat it?” Unfortunately, the fruit is totally flavorless. Just a tiny little ball of seeds and water. The little jerk-plant “mocks” us.

There may be hope though. Mock Strawberries came from India or south Asia where they’re called She Mei (Snake Strawberry). Apparently, the plant is used to control mosquito larvae in China (1959 Compendium of Chinese Indigenous Pesticides). I’m not quite sure how that works, but I’ll be conducting my own experiments this summer. If successful, I won’t feel so betrayed.