By Ian Vorster
Vaughn Walton, a professor in Oregon State’s Department of Horticulture, points at net-covered cages containing fruit flies, blueberries and what he calls artificial fruit — a chemical concoction that attracts the flies. “We place little disks of attractant in the middle of each cage, cover them with nets and release flies inside,” he says. “After two days, we collect the fruit, and we look at the infestation.”
The particular pest Walton is referring to is the spotted-wing drosophila (Drosophila suzukii), and it can have a negative annual economic impact of up to $500 million on soft fruit such as blueberries, raspberries, peaches and strawberries.
The researchers have been working for a number of years to develop an artificial attractant that encourages the flies to lay their eggs on or near it rather than in the fruit. In this particular experiment, Walton’s team found up to 76 percent reduction in egg laying on the blueberries using their synthetic fruit matrix. They are showing similar results on strawberries, which make up about 70 percent of all susceptible fruit worldwide. That efficacy is comparable with pesticides, but it has no insecticide in it at all. “That opens up industry markets significantly because it’s environmentally friendly,” he says.
The fly buzzed onto Walton’s radar in 2009 when he and colleagues from as far afield as Italy started working on the creation of an attractant. In 2017, Walton, together with OSU horticulturist and extension fruit expert Clive Kaiser and visiting Italian graduate student Gabriella Tait, were finally able to develop the first prototype of the product.
The team is now in the advanced developmental stage as they work on the most optimal commercial application — a means to spread it near the fruit so that the attractant can outfox the flies. With the help of OSU agricultural entomologist, Valerio Rossi Stacconi and Jennifer Field, a chemist and professor in the Department of Environmental and Molecular Toxicology at Oregon State, the scientists are refining an organic product that allows the chemicals to release at a slow and sustained rate. “We are essentially producing an economic benefit because of the combined lower cost of labor, and we are increasing its effectiveness,” says Stacconi. The longer the product remains active, the less that needs to be applied.
Brian Wall, assistant vice president for research, commercialization and industry partnering, in the OSU Research Office, sees great potential in this synthetic fruit solution to a pervasive pest problem. His team is committing $60,000 in support through the University Venture Development Fund, has filed a patent application, provided OSU Advantage Accelerator training, and is connecting with local entrepreneurs and investors who may be interested in supporting the work as is emerges.
“This is an outstanding example of how OSU research plays a key role in driving economic impact in Oregon and beyond,” Wall says.