Potential hosts of Prostephanus truncatus (Coleoptera: Bostrichidae) among native and agroforestry trees in Kenya

This study was carried out to establish the extent to which an invasive stored products pest, Prostephanus truncatus Horn exploits wood as a feeding and breeding resource in Kenya. Twenty seven out of 84 native and agroforestry trees and shrubs supported the breeding of P. truncatus under laboratory conditions. Adult survival (<1% to 18%) for 8 weeks was recorded on 51 tree species that did not support breeding. The breeding success of this beetle varied widely between host tree species and showed no obvious trends based on tree systematics or wood hardness. Studies of P. truncatus survival on two host tree species found that the greatest increase in the P. truncatus population occurred on stem sapwood, whilst the smallest population increase was on twigs. Breeding also varied greatly from season to season; studies on ten selected host species showed that reproduction was often greatest in wood samples collected and tested during the dry season in September. The implications of these findings for the management of P. truncatus infestations in farm stored maize are discussed.