Trapping tips, cultural controls, and how to test fruit will be among the topics covered by experts from Ohio State University.
“The bad news about this pest is that is it widespread and causes significant damage,” said Celeste Welty, an Ohio State University (OSU) Extension entomologist and associate professor of entomology, who also has an appointment with the Ohio Agricultural Research and Development Center (OARDC). OSU Extension and OARDC are the outreach and research arms, respectively, of the college.
“But once you identify it and know it is impacting your crops, it can be managed and beaten back. Early detection is a critical part of managing this pest.”
To help growers learn new management tips for spotted wing drosophila and new methods to trap and get rid of the pest, Welty, along with Jim Jasinski, an OSU Extension educator and integrated pest management specialist, will offer a webinar May 6 from 10:30 a.m. to noon.
The webinar will teach participants the basics of adult monitoring with traps, cultural controls, how to manage spotted wing drosophila with insecticides once detected, and how to determine if fruit is infested with larvae using a simple salt water test, she said.
The pest is known to cause significant losses for fruit growers in several states, including Michigan, where many blueberry, bramble and strawberry growers reported up to 50% fruit loss in 2012, according to a report from Michigan State University Extension.
“Once you find spotted wing drosophila, it takes rigorous insecticide use to manage it, including spraying weekly using a pesticide that can be applied close to harvest,” Welty said.
Some growers who do not want to spray are abandoning the production of berry crops until a biological control tactic can be developed, Welty said.
“Growers can determine if spotted wing drosophila is in their crops by setting up traps to monitor any activity,” she said.
The webinar will discuss trapping options, including a homemade one that may be more difficult to use or a purchased option that is easier to manage thanks to a new lure that is specialized to attract spotted wing drosophila.
“Growers who’d prefer to avoid using pesticides can instead try growing black raspberries or June harvest strawberries, as these two crops don’t seem to be as much of a problem with spotted wing drosophila,” Welty said. “There is also a pesticide available to use that is effective and is allowed in organic growing.”
Other management tips include:
- Do not delay harvesting: Pick as soon as fruit ripen.
- Keep harvested fruit cooled as soon as it is picked.
- Sanitation is critical. Collect and destroy unharvested or damaged fruit every two days. Put culls in a clear plastic bag and leave the bag in the sun for one week, or bury it 2 feet deep.
- Netting is a control option, especially for organic growers.
- If any spotted wing drosophila are found in the trap, then insecticides need to be applied to the fruit crop, starting when fruits begin to ripen or berries start to turn color, until the final harvest.
- Spray every seven days with insecticides that provide seven-days residual activity.
- Do a salt test weekly to see if the control program is working well. Put a sample of fruit in a bag with warm salty water and wait 15 minutes to see if any larvae are present.
Visit www.surveymonkey.com/s/SWDmm2015 to register for the May 6 webinar.
Source: Ohio State University news release