Submitted to: Journal of Applied Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/11/2013
Publication Date: 4/5/2013
Citation: Basoalto, E., Hilton, R., Knight, A.L. 2013. Factors affecting the efficacy of a vinegar trap for Drosophila suzukii (Diptera: Drosophilidae). Journal of Applied Entomology. 137:561-570. Interpretive Summary: The spotted wing fruit fly, Drosophila suzukii is an introduced pest from Asia now attacking many fruit crops in the United States. Effective, low-cost monitoring is an important component of detection and developing integrated programs using action thresholds and semiochemicals to minimize the use of insecticides. Researchers at the USDA, ARS, Yakima Agricultural Research Laboratory, Wapato, WA developed a new trap and in collaboration with scientists from Oregon State University compared it with a number of other trap designs. These comparative studies clarified the factors, such as color/pattern, cumulative area of openings, and the size of the trap affecting fly captures. These data can be used to develop a standardized trapping program for this important new pest.
Technical Abstract: Studies were conducted to develop an optimized, economical trap for monitoring the spotted wing fruit fly, Drosophila suzukii Matsumura. Flies were attracted to dark colors ranging from red to black compared with low attraction to white, yellow, and light blue. Similarly, fly catches in 237 ml plastic ‘spice’ jars with ten 0.48-cm holes and baited with apple cider vinegar were significantly higher in jars with red or black than white caps. The use of an alternating set of three, 1.5-cm wide horizontal red, black, and red bands (Zorro trap) significantly increased fly catches compared with the use of a 4.5-cm all-red or all-black strip. This increase was associated with a significantly higher proportion of flies first landing on the side instead of the cap of the Zorro trap compared with the all-red or all-black spice jars. These data were used to develop a predictive model to define total fly capture as a function of trap color, cumulative area of entry holes, and the length of the trapping portion of the trap. Total fly catches by the Zorro trap was compared to other red and clear plastic traps in five trials conducted in cherry, blueberry, and wild blackberry. Comparisons included a commercial red-capped 200-ml trap with two 0.63 cm holes and clear and red 473-ml and clear 946-ml plastic cups with six or ten 0.48 or 0.63-cm holes. The model was successfully validated suggesting that trap performance can be predicted based on a few characteristics. The Zorro trap has many advantages including its durability, small size, and availability. In addition, a lower proportion of non-target drosophilids were caught in the Zorro than the various cup traps.