Fungi isolated from Picea abies infested by the bark beetle Ips typographus in the Bialowieza forest in north-eastern Poland

P>The assemblage of fungi occurring in the sapwood of Norway spruce (Picea abies) and in bark beetle galleries following attack by the Eurasian spruce bark beetle Ips typographus was investigated in the Bialowieza forest in north-eastern Poland. Fungi were isolated from blue-stained sapwood of beetle-infested spruce trees in June 2002, and a few isolates were also obtained from ascospores and conidia taken from perithecia and asexual structures occurring in the gallery systems of the insects. The mycobiota of I. typographus in the Bialowieza forest was dominated by ophiostomatoid fungi, which were represented by seven species. Four species, including Ceratocystis polonica, Grosmannia penicillata, Ophiostoma ainoae and Ophiostoma bicolor were isolated at high frequencies, whereas three other taxa, Ceratocystiopsis minuta, Ceratocystiopsis alba and a Pesotum sp. were rare. The anamorphic fungus Graphium fimbriisporum and yeasts also occurred occasionally. In addition, the basidiomycete Gloeocystidium ipidophilum was relatively common. The pathogenic blue-stain fungus C. polonica was the dominant fungal associate of I. typographus in the Bialowieza forest, which is consistent with a previous study at this area in the 1930s. Ceratocystis polonica was the most frequently isolated species at the leading edge of fungal colonization in the sapwood and had on an average penetrated deeper into the wood than other fungal associates. This suggests that it acts as a primary invader into the sapwood after attack by I. typographus in the Bialowieza forest, followed by O. bicolor, O. ainoae, G. ipidophilum and G. penicillata. Thus far, the Bialowieza forest is one of the few areas in Europe, where C. polonica has been reported as a dominate fungal associate of I. typographus.