Ophiostomatoid fungi associated with the invasive pine-infesting bark beetle, Dendroctonus valens, in China

Abstract

Bark beetles (Coleoptera: Scolytinae) are common vectors of ophiostomatoid fungi, including several primary tree pathogens as well as important agents of sapstain. Dendroctonus valens, considered a secondary bark beetle in its native, North America, has caused unprecedented tree mortality in China. Several species of ophiostomatoid fungi are associated with the beetle in North America, but little research has been done on the fungi associated with this invasive bark beetle in China. The aim of this study was to isolate and characterize ophiostomatoid fungi associated with this D. valens in China. Ten ophiostomatoid fungi (Leptographium procerum, L. pini-densiflorae, L. truncatum, Hyalorhinocladiella pinicola, Ophiostoma flocossum, O. ips, O. minus, O. piceae, O. abietinum and an undescribed taxon close to O. rectangulosporium) were isolated from the bark beetle or its galleries and identified using morphology and DNA sequence comparisons. Leptographium truncatum, L. pini-densiflorae, H. pinicola, O. flocossum, and O. minus are reported from China for the first time. Leptographium procerum was the most frequently isolated species.