Abstract:
The western spotted cucumber beetle (Diabrotica undecimpunctata
undecimpunctata) and the western striped cucumber beetle (Acalymma trivittatum) are
pests of many crops, including vegetable, fruit, and nursery crops. Pesticides are
commonly used to control this pest. Trap and kill technologies are under development as
use in an alternative control for cucumber beetles, the trap design includes three parts: a
kairomone, cucurbitacin “beetle bar”, and plastic or plexiglass trap body. This project had
three objectives, including: (1) to evaluate the effect of temperature on the degradation of
the cucurbitacin concentration in the bait components of a trap and kill technology, (2) to
evaluate kairomone lure longevity under field conditions, and (3) to evaluate
effectiveness of alternative traps and design modifications on beetle capture rate. High
Performance Liquid Chromatography was used to identify cucurbitacin degradation. The
cucurbitacin content of the bait declined 23% over ten weeks at temperatures above 32°C
but remained relatively stable at temperatures below 21°C. Duration of kairomone lure
attractivity was determined in the field by beetle capture rate on variously aged
kairomones. The kairomone was the most attractive as fresh or 1-day post prep lure, in
comparison to older lures or no lures. A 35-day old lure caught more beetles than a nolure
trap. Beetle capture rate was used to evaluate trap design efficiency. The dilution of
the bait to 10% cucurbitacin increased beetle capture rate. A round trap design, called the
OSU lab trap, was the most efficient trap for both spotted and striped beetles, while the
modifications of a vent and minilure were inconclusive.
