The purpose of our work was to determine whether eight-toothed bark beetle (Ips typographus [L.]) and six-toothed bark beetle (Pityogenes calchographus [L.]) disseminate fungi, which associated fungi these are, and in what portions they are represented. The beetles were collected at current outbreak locations. They were inoculated into pieces of wood of a healthy, recently felled spruce. Pieces of wood and bark collected from around the holes in which the bark beetles had been previously placed, were afterwards placed on agar. Our work comprised picking the bark beetles in the field, laboratory work and microscopy, but we also tried to determine the relationship between bark beetles and blue-stain fungi, why they are associated so often and what their effect on the tree is. We found out that all beetles were infected with fungi. Among 261 fungi that had developed in 240 testers we confirmed the existence of only 3 species of blue-stain fungi and a probability of another 4 species of blue-stain fungi. Most common and most virulent Ceratocystis polonica has never appeared in the results, but we did find Ophiostoma penicillatum and Ophiostoma bicolor and also 51 fungi from the Gliocladium genus. The latter were not detected in researches, made in other countries. The most frequent fungus was Penicillinum spp. (145 specimens). We studied the sanitary felling due to bark beetles and found out that in Slovenia the outbreak started in 2001, culminated in 2005 and is now in the process of ceasing.
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