Monday, December 10, 2007 - 10:53 AM

Emergence trap evaluation and seasonal variation in infestation of blueberry gall midge (Diptera: Cecidomyiidae) in rabbiteye blueberries

Craig R. Roubos, and Oscar E. Liburd, University of Florida, Entomology and Nematology Department, Bldg 970 Natural Area Drive, Gainesville, FL

Blueberry gall midge, Dasineura oxycoccana Johnson, is a key pest of rabbiteye blueberries (Vaccinium ashei). Larvae feed in both flower and leaf buds. Monitoring adult midges is difficult due to their small size and short lifespan. An effective method for monitoring adult midges early in the season would be useful for making management decisions. We evaluated three emergence trap types for monitoring blueberry gall midge adults. The trap types were glass jar, Petri dish, and plastic lid. Traps were placed at the bases of blueberry plants and checked weekly. The Petri dish trap captured significantly more midge adults than the glass jar and plastic lid traps in both 2006 and 2007. The sex ratio of adult midges was 1:1 (male: female) and was not significantly different for any trap types. In addition to evaluating emergence traps, we investigated the distribution of gall midge infestation in a blueberry planting. Infested flower buds were collected from three different areas within the planting: border with vegetation, plot center, and border without vegetation. Larvae exiting the buds were counted and analyzed. Significantly more midges were recorded in the border with vegetation compared with the other treatments (areas) where buds were collected. Few midges were recorded in the border without vegetation.

Species 1: Diptera Cecidomyiidae Dasineura oxycoccana (blueberry gall midge, cranberry tipworm)