Irradiation for quarantine control of coffee berry borer, Hypothenumus hampei (Coleoptera: Curculionidae: Scolytinae) in coffee and a proposed generic dose for snout beetles (Coleoptera: Curculionoidea)

Authors: Follett, Peter

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2018
Publication Date: 6/1/2018
Citation: Follett, P.A. 2018. Irradiation for quarantine control of coffee berry borer, Hypothenumus hampei (Coleoptera: Curculionidae: Scolytinae) in coffee and a proposed generic dose for snout beetles (Coleoptera: Curculionoidea). Journal of Economic Entomology. 111(4):1633-1637. https://doi.org/10.1093/jee/toy123.
DOI: https://doi.org/10.1093/jee/toy123

Interpretive Summary: Coffee berry borer is the most serious insect pest of coffee worldwide and a relatively new invasive species in Hawaii that causes economic losses and quarantine restrictions. Green coffee used in blending and roasting is traded between islands and may be subjected to fumigation or freezing for disinfestation of coffee berry borer. Alternative disinfestation treatments would be desirable and irradiation is a viable option in Hawaii. In total, 6,598 adult coffee berry borers naturally infesting dried coffee berries were irradiated at 100 Gy and produced no viable offspring, whereas 1,033 unirradiated controls produced 145 eggs, 44 larvae and 58 pupae at 3 weeks post treatment. Irradiation treatment at 100 Gy could be used to safely move green coffee between islands.

Technical Abstract: Coffee berry borer, Hypothenemus hampei, is the most serious insect pest of coffee worldwide. Green coffee used in blending and roasting is traded between countries and may be subjected to fumigation for disinfestation of coffee berry borer. For example, green coffee shipped to Hawaii from the U.S. mainland must be treated with methyl bromide. Irradiation is an alternative disinfestation treatment option. Dose response tests were conducted with adult beetles to identify a sterilizing dose, followed by large-scale confirmatory tests with adults infesting coffee berries at 100 Gy (measured doses 89-98 Gy). In total, 6,598 adult coffee berry borers naturally infesting dried coffee berries were irradiated at 100 Gy and produced no viable offspring, whereas 1,033 unirradiated controls produced 145 eggs, 44 larvae and 58 pupae at 3 weeks post treatment. This is the first study to develop a postharvest irradiation treatment for a scoytine bark beetle, and supports other studies suggesting 150 Gy is sufficient to prevent reproduction in snout beetles, superfamily Curculionoidea.