Canola Oil as a Kairomonal Attractant of Rangeland Grasshoppers:

an Economical Liquid Bait for Insecticide Formulation

Jeffrey A. Lockwood1, Narisu2, Scott P. Schell2, and Dale R. Lockwood3

1 Association for Applied Acridology, International
Entomology Section,
Department of Renewable Resources,
University of Wyoming,
Laramie, Wyoming 82071-3354

2 Entomology Section,
Department of Renewable Resources,
University of Wyoming,
Laramie, Wyoming 82071-3354

3 Dept. of Wildlife, Fish and Conservation Biology,
University of California,
One Shields Avenue, Davis, CA 95616

Short title: Canola oil as grasshopper bait

ABSTRACT

Micro-, meso-, and macro-scale experiments demonstrated that canola oil is an attractant of rangeland grasshoppers and a viable insecticide carrier. In laboratory-based micro-scale tests, olfactometry revealed a significant, positive chemotaxis of Melanoplus sanguinipes in response to a canola and olive oil mixture. Field-based, micro-scale tests with airbrush applications of 5 ml of canola oil (equivalent to 500 liter per ha) to centers of aluminum rings (0.1 m²) increased grasshopper densities by 4-fold after 1 h. Applications of canola oil (10 and 100 µl; equivalent to 1 and 10 liter per ha) with the same technique increased the grasshopper density by 3- to 5-fold from 1 to 24 h after application. Meso-scale tests using fluorescent powder for mark-release-resight/recapture of grasshoppers showed applications of 1 and 10 liter of canola oil per ha significantly increased grasshopper densities in treated sites over a period of 36 h. A macro-scale aerial application of 1 liter per ha of canola oil applied in alternating 30 m treated and untreated swaths demonstrated that attraction of rangeland grasshoppers started 1 d after the treatment, peaked after 3 d, and gradually declined from 7 to 21 d. Late instar nymphs and adults of rangeland pest species of Gomphocerinae and Melanoplinae were strongly attracted to treated strips. Grasshopper density across the treated plot (both within and between swaths) was higher than in the untreated plot for 21 d after the application. Macro-scale aerial applications of carbaryl formulated in canola oil (120 g per ha of Sevin XLR in 237 ml of canola oil) showed that this carrier increased grasshopper mortality by 24 to 85%, at 7 to 21 d after treatment, relative to a water-based application. These findings suggest that this carrier could markedly enhance the efficacy of insecticides in grasshopper control programs.

Key words: semiochemical, target specificity, pest management, formulation, reduced agent/area treatments


The entire report will soon be available online.

Available as: Corresponding author:
University of Wyoming PhD Dissertation Jeffrey A. Lockwood
For Submission to: Entomology Section
International Journal of Pest Management Department of Renewable Resources
University of Wyoming
Laramie, Wyoming 82071-3354
Phone (307) 766-4260
Fax (307) 766-5025
Email: lockwood@uwyo.edu