Survey of Trogoderma species (Coleoptera: Dermestidae) associated with international trade of dried distiller’s grains and solubles in the USA

Abstract

Dried distiller’s grains and solubles, DDGS, is a valuable commodity with substantial international trade. Vietnam discovered an infestation of Trogoderma inclusum, an actionable quarantine pest, in DDGS from the USA in 2012. All subsequent shipments to Vietnam were required to be fumigated. A shipment to Vietnam from the USA 2015 was then discovered with T. variabile. We surveyed the presence and activity of T. inclusum and T. variabile at locations in the USA that provide DDGSs for shipment to Vietnam. Seven facilities in four states that either produced DDGSs or that facilitated bulk shipments were studied. Pheromone traps were deployed at each location and monitored for several weeks. T. variaible was trapped at all seven sites while T. inclusum was trapped at just five of these. T. variabile were captured in nearly every trapping period and at higher numbers than T. inclusum at five locations, while two locations captured more T. inclusum than T. variabile. Spatial variation seemed to occur within each site, but there was no common pattern among facilities. Substantial numbers of beetles were caught in the outdoor sticky flight traps for most locations, except for relatively low flight trap numbers at locations 1, 4 and 6. The results show that T. variabile and T. inclusum are commonly associated with DDGSs produced in the USA, that these beetles could infest product being shipped overseas, and provide information that can be used to develop risk assessment and pest management programs for the future.

Keywords

• coleoptera
• dermestidae
• ddgs
• vietnam
• quarantine