Title

Development of a reliable monitoring and perimeter trap crop management system for the pepper maggot (Diptera: Tephritidae) Zonosemata electa (Say)

Date of Completion

January 2003

Keywords

Biology, Entomology

Degree

Ph.D.

Abstract

Ammonium-baited (Stills-style) traps were tested in several in- and near-field positions to find a reliable way to monitor for pepper maggot [Zonosemata electa (Say)] flies. Trapping results indicated that the flies occupy tree canopies adjacent to fields when not on host plants. Traps hung in the canopies of nearby trees, caught more Z. electa flies than when positioned lower along the treeline or in pepper fields. More pepper maggot flies were captured in sugar maples than in choke cherry trees and more were captured at higher canopy elevations than at lower heights. Pepper maggot flies can be reliably detected with Stills-style traps positioned at ≈6.4 m height within the canopy of sugar maple trees adjacent to pepper fields. ^ Oviposition scars and fruit infestations were quantified over time by examining fruit from pepper plants, which were protected from flies with row covers, through different portions of the adult flight period. Peak oviposition and infestation occurred one to four weeks after initial egg laying began. Fruit oviposition scars also are useful site-specific indicators of pepper maggot presence/absence and aid in timing initial and repeat insecticide applications. ^ Three management strategies were evaluated for effectiveness in protecting bell peppers from oviposition and infestation by pepper maggots. The treatment strategies included a perimeter trap crop of hot cherry peppers, border-row insecticide applications and a combination of the two strategies. All three treatments significantly reduced pepper maggot damage on bell peppers. The sprayed perimeter trap crop treatment reduced the natural maggot infestation by 91%, and resulted in harvests that were 98–100% pest-free in both research and commercial settings. Commercial farmers that used the combination strategy improved their pepper maggot control and experienced better control than farms that had used well-timed, full-field sprays. Farmers that used perimeter trap cropping stated that the technique simplified pepper production and marketing, reduced pesticide use, improved crop quality, increased profitability and had additional worker protection, personnel management, pest control and environmental benefits. Economic analysis of the perimeter trap cropping strategy confirmed an overall improvement in crop profitability ($13–$378/hectare). ^