|Sim, Sheina - University Of Hawaii|
|Brill, Eva - University Of Hawaii|
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/3/2015
Publication Date: 10/19/2015
Citation: Sim, S.A., Yoneishi, N., Brill, E., Geib, S.M., Follett, P.A. 2015. Molecular markers detect cryptic predation on coffee berry borer (Coleoptera: Curculionidae) by silvanid and laemophloeid flat bark beetles (Coleoptera: Silvanidae, Laemophloeidae) in coffee beans. Journal of Economic Entomology. 109(1):100-105.
Interpretive Summary: The coffee berry borer, Hypothenemus hampei, is an invasive and destructive agricultural pest that has been recently introduced in Hawai’i which threatens a multimillion dollar industry. Current integrated pest management programs can be supplemented by the addition of a biocontrol agent. Two beetle species, the silvanid flat bark beetle, Cathartus quadricollis, and the laemophloeid bark beetle, Leptophloeus sp., have been observed in H.hampei infested coffee cherries, but their direct feeding on H.hampei had not been observed. In this study, molecular methods were developed and used to demonstrate that C.quadricollis and Leptophloeus sp. prey on H.hampei in coffee farms. This finding provides evidence for the use of C.quadricollis and Leptophloeus sp. as agents for biocontrol on H.hampei.
Technical Abstract: The coffee berry borer, Hypothenemus hampei(Coleoptera: Curculionidae)(Ferrari), is a serious pest of coffee worldwide and has been recently introduced in Hawai’i, first detected in the state in 2010. Adult silvanid flat bark beetles, Cathartus quadricollis (Coleoptera: Silvanidae) and adult laemophloeid flat bark beetles Leptophloeus sp.(Coleoptera: Laemophloeidae), have been observed in and around H.hampei infested overripe coffee cherry and coffee raisins. Colony reared C.quadricollis and Leptophloeus sp. prey upon all life stages of H.hampei under laboratory conditions, but due to the fact that the H.hampei life cycle occurs almost exclusively within a coffee bean, it is unknown if C.quadricollis and Leptophloeus sp. consume H.hampei as prey in the wild. To demonstrate predation of H.hampei by adult C. quadricollis and Leptophloeus sp., a molecular assay was developed utilizing species-specific primers targeting short regions (111-240 bp) of the mitochondrial COI gene to determine the presence of each species. Using these primers, wild C.quadricollis and Leptophloeus sp.were collected and screened for presence of H.hampei DNA using PCR. Analysis of collections from various coffee farms showed that the predatory beetles were feeding on H.hampei. Further laboratory testing showed that H.hampei DNA could be detected from in predator samples for as long as 48 hours after feeding, indicating the wild-caught predator samples had preyed on H.hampei within 2 days of sampling. This study demonstrates the utility of molecular markers for the study of the ecology and feeding of predators and prey with cryptic behavior.