The invasion of Pinus radiata seedlings by sapstain fungi, following attack by the Black Pine Bark Beetle, Hylastes ater (Coleoptera: Scolytidae)

Abstract

The relationship between sub-lethal Pinus radiata seedling attack by the Black Pine Bark Beetle, Hylastes ater, and subsequent invasion by sapstain fungi were investigated. Results show that seedlings attacked by H. ater were more likely to be infected by species of sapstain fungi. In addition, the likelihood of invasion increased with increasing severity of H. ater attack. Fifty percent of severely attacked seedlings were infected by one or more species of sapstain fungi. In total, six species of sapstain fungi were isolated from seedlings. Ophiostoma huntii was the most common species isolated from seedlings. H. ater was found to vector one species of sapstain fungi, although other sapstain species have been found to be associated with H. ater in other studies. Further research is required to fully determine the role of H. ater as a vector of sapstain fungi in New Zealand.