To Örebro University

Ophiostomatalean fungi may facilitate bark beetle colonization and reproduction. In the present study of the fungal community associated with bark beetle spe-cies belonging to Tomicus in Yunnan, China, six ophios-tomatalean fungi (Ophiostoma canum, O. ips, O. tingens, Leptographium yunnanense, Leptographium sp. 1 and Lep-tographium sp. 2) were isolated from the beetles or their galleries; O. canum was the most common fungal species. The distribution of O. canum was associated with stands heavily damaged by Tomicus species and a higher percentage of valid galleries of Tomicus yunnanensis and T. minor in Yunnan pine (Pinus yunnanensis). After inoculation of Yun-nan pine with the fungus, a phloem reaction zone formed and monoterpenes accumulated in the phloem. These results suggested that O. canum was pathogenic to Yunnan pine and that the wide distribution of the fungus might be beneficial to reproduction of pine shoot beetles in Yunnan pine. How-ever, because the reaction zone and monoterpene accumu-lation were mild, fungal damage of Yunnan pine might be limited. A more integrated study considering all the fungal species should be done to better understand the interactions among bark beetles, blue-stain fungi, and the tree hosts in the region.