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Allison Henderson
Master of Science Candidate
Centre for Environmental Biology
Simon Fraser University, Burnaby B.C.,Canada

The Project The goal of my research to better understand the basic biology of two tropical, polyphagous, economically important weevils Exophthalmus jekelianus and Exophthalmus sp. (Coleoptera: Curculionidae) that cause severe defoliation to Costa Rican coffee and citrus, respectively. Current management relies on frequent application of insecticides. Due to low coffee prices and new production standards for more "ecologically friendly" coffee and citrus, Costa Rican coffee and citrus growers require alternative weevil management techniques that reduce their use of insecticides.

Potential Solution By exploring the chemical and behavioural ecology of Exophthalmus jekelianus and Exophthalmus sp. , I aim to identify pheromones for use in a pheromone-based Integrated Pest Management Plan (IPM) for coffee and citrus in Costa Rica. This IPM plan will reduce the amount of insecticide applied by using identified pheromones in mass trap or attract and infect tactics. This IPM plan may significantly enhance crop production and will inevitably affect the lives of men and women involved in growing coffee and citrus in Costa Rica.

Exophthalmus jekelianus Feeding by E. jekelianus can cause severe damage to coffee plants by directly limiting growth and indirectly facilitating entry of the fungus, Phoma costarricensis which causes Derrite, a very important coffee disease.

Exophthalmus sp. Exophthalmus sp. has recently been identified as a problem on citrus farms in northern Costa Rica. Defoliation by Exophthalmus sp. causes severe damage to young citrus plants by limiting growth and facilitating the entrance of plant pathogens.

Social Considerations While in Costa Rica, I will conduct interviews with members of the coffee and citrus production systems to determine if pheromone trapping as part of a weevil Integrated Pest Management plan is acceptable to coffee and citrus growers.

I am working under the joint supervision of Dr. Bernard Roitberg at Simon Fraser University, Canada and Dr. A. C. Oehlschlager of ChemTica Internacional S.A., San Jose, Costa Rica. This project is financially supported by an Industrial Post Graduate Scholarship from the Natural Sciences and Engineering Research Council of Canada and a Latin America and Caribbean Research Exchange Grant from the AUCC.