Source: North Carolina State University Press Release.
harvest.cals.ncsu.edu
Raleigh, North Carolina (March 15, 2013)--Humans aren’t
the only species with a sweet tooth. Research from North Carolina State
University shows that the invasive spotted-wing vinegar fly (Drosophila
suzukii) also prefers sweet, soft fruit – giving us new insight into a
species that has spread across the United States over the past four
years and threatens to cause hundreds of millions of dollars in damage
to U.S. fruit crops.
“Because we know that D. suzukii prefers softer, sweeter
fruit, we can focus our research efforts into which wild fruits may
serve as reservoirs for this species and help identify new crops that
might be at risk,” says Dr. Hannah Burrack, an assistant professor of
entomology at NC State and lead author of a paper on the research.
“These findings may also be a starting point for plant breeders
interested in developing new fruit varieties that are more resistant to
D. suzukii.”
Originally from east Asia, D. suzukii were first
detected in California in 2008. They have since spread to states from
Wisconsin to North Carolina to Florida. The female flies use serrated
blades on the tip of their abdomens to cut through the skin of ripe
fruit and lay their eggs. The eggs hatch into larvae that feed on the
flesh of the fruit until they reach maturity – ruining the fruit in the
process.
Sellers go to great pains to remove infested fruit
before it reaches the marketplace, so consumers won’t notice a
difference in fruit quality. But infestations can cause significant
economic problems for fruit growers. For example, researchers estimate
that D. suzukii has the potential to destroy 40 percent of blackberry
and raspberry crops in the eastern U.S., which would affect berry prices
and availability.
D. suzukii already causes tens of millions of dollars in
crop damage annually to cherries, raspberries, blackberries,
blueberries and strawberries. But researchers estimate that losses could
climb into the hundreds of millions of dollars per year if the pest
can’t be controlled.
While ongoing studies explore pesticide-based approaches
to control D. suzukii, the new research from NC State should help
scientists and farmers with other control options.
For example, the study found that D. suzukii are more
likely to infest certain varieties of raspberries and blackberries. This
means growers may be able to limit crop damage by planting more of the
varieties that D. suzukii tend to avoid. Similarly, this information
allows farmers to focus pesticide treatment on varieties that are most
susceptible to infestation.
The three-year study evaluated D. suzukii impacts in
commercial blackberry and raspberry crops in North Carolina, and also
encompassed laboratory experiments to help researchers determine which
characteristics made fruits more likely to be infested. The work was
supported by the Southern Region Small Fruit Consortium, North Carolina
Tobacco Trust Fund Commission, North Carolina Department of Food and
Agriculture, U.S. Department of Agriculture and North Carolina Blueberry
Council.
The paper, “Variation in selection and utilization of
host crops in the field and laboratory by Drosophila suzukii Matsumara
(Diptera: Drosophilidae), an invasive frugivore,” was published online
March 14 in Pest Management Science. Co-authors are Dr. Gina Fernandez, a
professor of horticultural science at NC State; Taylor Spivey, an
undergraduate at Brevard College; and Dylan Kraus, an undergraduate at
NC State.
