This document briefly discusses the most relevant Integrated Pest Management (IPM) practices that are recommended for Spotted Wing Drosophila Management (SWD) in berry crops. The “1-2-3” approach to SWD management is meant to provide easy-to-understand steps to manage SWD in small farms. The three main components being discussed here are monitoring, cultural practices, and timely application of insecticides.
For 2014, a monitoring program for susceptible crops is recommended throughout the harvest season. Place one monitoring trap baited with active dry yeast (1/2 tablespoon), sugar (2 tablespoons) and water (6 ounces) every 2-3 acres (Washington State Univ. recommends 1 trap in each crop or 1 trap per acre for large plantings). The trap needs to be hung on a plant, stake, or trellis 3–5 ft. or feet above the ground on the most shaded / coolest side of the plant canopy.
Articles discussing the importance of SWD monitoring, trap construction, and monitoring protocols can be found athttp://www.lincolnu.edu/web/programs-and-projects/ipm
2. CULTURAL PRACTICES
Cultural controls are practices that reduce the establishment, reproduction, dispersal, and survival of immature SWD.
No action threshold is available for SWD and in other states traps have not consistently been able to detect adults prior to fruit infestations. Based on this information, Michigan State University researchers are recommending a more conservative approach involving application of insecticides when SWD are captured by monitoring traps and the crop being protected has the first fruit beginning to soften and turn color.
It is important to highlight that an IPM program includes the use of monitoring traps to assess adult SWD population levels. Quantifying fruit infestation through fruit sampling is critical to determine the effectiveness of control systems implemented against SWD.
For the last five years or so, researchers have been evaluating numerous insecticides to identify the products that provide effective SWD control while reducing negative impacts to non-target organisms including pollinators. A number of registered conventional insecticides have shown to be effective against SWD in recent trials by Michigan State University researchers. Insecticides with fast knockdown activity such as the organophosphate Malathion*, the pyrethroids Asana (esfenvalerate), Danitol (fenpropathrin), Mustang Max (Zeta-cypermethrin), and Brigade (bifenthrin), and the spinosyns Delegate and Entrust (organic) have performed best. In a recent paper, researchers from Michigan State University (Van Timmeren and Isaacs, 2013) documented that spinosad (Entrust) and Spinetoram (Delegate) consistently performed as well as some pyrethroids such as Zeta-cypermethrin (Mustang Max). Malathion also showed good performance. Most insecticides lost efficacy after rainfall, and one of the exceptions was Zeta-cypermethrin (Mustang Max). Efficacy of most treatments was reduced greatly after exposure to just over 2 cm of rain. By one week after treatment adult mortality was not significantly different from the untreated controls for most insecticides that had been exposed to rain.
*While effective at suppressing SWD, malation degrades with UV light, therefore increasing the rate could help mitigate the effects of environmental degradation of this insecticide.
Research done in Florida also indicates that Danitol, Mustang Max, and Delegate performed equally well at reducing adult SWD activity and injury to blueberries.
Cornell University SWD website: http://www.fruit.cornell.edu/spottedwing/
Lincoln University IPM program: http://www.lincolnu.edu/web/programs-and-projects/ipm and http://www.LU-IPM.net
Michigan State University: http://www.ipm.msu.edu/invasive_species/spotted_wing_drosophila
North Carolina State University: http://ncsmallfruitsipm.blogspot.com/p/spotted-wing-drosophila-general.html
Oregon State University: http://spottedwing.org
Financial support for research and extension activities on Spotted Wing Drosophila and Brown Marmorated Stink Bug was provided by USDA-NIFA and the Missouri Department of Agriculture Specialty Crops Block Grant grants program to the LU IPM program.
REVISED: September 30, 2015