The blueberry maggot, Rhagoletis mendax Curran is the key late-season pest of blueberries, Vaccinium spp., in eastern and mid-western United States. Currently, ammonium baited PheroconŽ AM yellow boards and green spheres are used for monitoring sexually immature and mature flies, respectively. In an attempt to develop and refine blueberry maggot fly monitoring programs, we evaluated several synthetic blueberry volatile compounds over two seasons in field and laboratory experiments. In 1999, the following compounds were screened for their attractiveness: ammonium acetate, cis-3-hexen-1-ol, geraniol, beta-caryophyllene, alpha-terpiniol, trans-2-hexen-1-ol, 6-methyl-5-hepten-2-one, linalool, and trans-2-hexen-al. Volatile compounds (3 mL) were loaded into Beem capsules and polyethylene vials and subsequently attached to 9-cm diam green plastic spheres. Spheres were hung within blueberry bushes approximately 15 m apart and 20 m between blocks of highbush blueberries in Rhode Island and Michigan. In 2000, we evaluated different release-rates of selected blueberry volatile compounds within cultivars of different phenologies in Michigan. Treatments included geraniol, cis-3-hexen-1-ol, trans-2-hexen-1-ol, linalool, and untreated control and were compared against the standard ammonium acetate bait currently used in blueberry maggot fly monitoring programs. In Rhode Island (2000), the 1999 study was repeated, with the inclusion of butyl butanoate as an additional treatment. Traps baited with butyl butanoate and trans-2-hexenal were more attractive than control spheres in the field, but were not significantly more attractive than spheres baited with ammonium acetate. In field studies, a high load-rate of cis-3-hexen-1-ol was attractive to R. mendax as flies reached sexual maturity. In laboratory studies, R. mendax responses to synthetic volatile compounds were similar to field studies in some treatments when flies were given choice tests against an untreated control.
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA