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Japanese pine sawyer beetle (Monochamus alternatus) is an economically important pest in coniferous trees. Ophiostoma ips was isolated from the beetle and identified based on analysis of morphological properties and the β-tubulin gene sequence. The fungus easily produced perithecia with a long neck on malt extract agar and its ascospores were rectangular shaped. This is first report of Ophiostoma species associated with the pinewood nematode vector beetle in Korea.

A Mariannaea fungus was isolated during investigation of an elm tree infested with unidentified beetles. Based on morphological characteristics and molecular analysis of the internal transcribed spacer rDNA sequence, the fungus was identified as Mariannaea elegans var. elegans. Fungal growth was better on malt extract agar than on potato dextrose agar and oatmeal agar. Optimal temperature and pH for growth of the fungus were 30℃ and pH 7.0, respectively. The fungus was found to have the ability to produce extracellular enzymes such as amylase, β-glucosidase, cellulase, and protease. This is first report on M. elegans var. elegans in Korea.

One of the sapstain fungal species isolated from the stained sapwood of a Japanese black pine in Korea was characterized. The fungal species is tolerant to cycloheximide and has Petosum-like synnema and Sporothrix type synanamorph which are found in the anamorphs of the Ophiostoma piceae complex group. But the species could not form perithecia on MEA. Based on cultural and morphological properties and analysis of the -tubulin gene sequence, the fungal species was identified as Ophiostoma quercus. Here, we report mycological characteristics of the anamorphic stage of Ophiostoma quercus isolated in Korea.

During an investigation of fungi from an elm tree infested with bark beetles in Korea, one isolate, DUCC401, was isolated from elm wood. Based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer and 28S rDNA (large subunit) sequences, the isolate, DUCC401, was identified as Mariannaea samuelsii. Mycelia of the fungus grew faster on malt extract agar than on potato dextrose agar and oatmeal agar media. Temperature and pH for optimal growth of fungal mycelia were 25℃ and pH 7.0, respectively. The fungus demonstrated the capacity to degrade cellobiose, starch, and xylan. This is the first report on isolation of Mariannaea samuelsii in Korea.

Wood discoloration caused by sapstain fungi is one of the problematicissues in the forest products industry. Sapstain fungi include treepathogens belonging to Ophiostoma, Ceratocystis, and Grosmanniagenera. During a recent survey on sapstain fungi occurring inJapanese red pine ( Pinus densiflora ) logs and lumber in Korea, deepreddish brown stain that had never been reported in wood staindamage was observed. We isolated and identified Ophiostomafungus from the region of reddish brown stain (Fig. 1). A voucherspecimen was deposited at Korean Agriculture Culture Collection,Suwon, Korea (KACC 43403). The fungus grew optimally at 30

Sapstain fungi that cause blue or black discolorations of sapwood indiverse trees are one of the important fungal groups in forest healthas tree pathogens, and in forest products industry as wood-stainers(Seifert, 1993). Sapstain, caused by fungi, is the cosmetic damage ofwood that reduces wood quality and the values of commercial woodproducts. In July 2006, bluish or brown colored signs of sapstainwere found on cut sapwood of Japanese black pine (Pinusthunbergii) in Taean, Korea (Fig. 1A). The signs of sapstain werealso found on cut sapwood of Japanese black pine infected withpinewood nematode in Jinju in June 2007. Voucher specimens weredeposited at Dankook University Culture Collection, Cheonan,Korea (DKM 0510, 0410, 0412, 0413, 0601).The fungal colony was brown and dark on MEA, light brown onPDA and black on oat meal agar (Fig. 1B). Optimal growthtemperature and pH for the fungus was 22 and pH 6. The fungusshowed tolerance to cycloheximide (250 μg/ml). The optimal pHfor growth was on PDA and MEA. Observation of morphologicalfeatures on a phase-contrast light microscope (Karl Zeiss Axioskop40) and a scanning electron microscope (Hitachi S-4200) revealedthat the fungus has Sporothrix and Pesotum anamorph of O. piceae-complex. Conidial mass on apex of synnema was milky color.Synnema were dark brown and 500-1300 ( −1600)μm. Synemmat-ousconidia were hyaline and 5-15×1-3.5 μ m (Fig. 1C-E). Peritheciaand ascospores were not found in our cultures. To confirm the identity of this fungus, partial β-tubulin gene wasamplified with primers T10 and BT12 (Kim et al., 2003) and directlysequenced. The determined nucleotide sequence was deposited inGenBank (EU012505). The determined sequence shared 100%sequence identity with those of O. piceae. Based on β-tubulin genesequence, a cladogram was constructed using PAUP by the neigh-bor-joining method with the heuristic search option (Swofford,2002). The fungus grouped with O. piceae (Fig. 2). This moleculardata confirmed the fungus is O. piceae. An inoculation test on woodchips of Japanese pine displayed that the fungus colonized anddeveloped dark and/or brown stain in the chips (Fig. 3B). On theinoculated chip, the fungus formed its typical brown pigmentedsynnema having a droplet of conidial mass (Fig. 3C). So far m, ore than 150 species of Ophiostoma have been descrbed,ibut their occurrence has rarely been studied in Korea. This is the firstreport of O. piceae in Korea. Since we isolated O. piceae from a pinediseased by pinewood nematode that recently has devastated pinetrees in Korea, further study on Ophiostoma fungi should be done toexplore their impact on forest health and wood discoloring damage.

An Ophiostoma fungus was isolated from a stump of Pinus thunbergii in a forest on the West coast of Korea. Microscopic analysis using a light microscope, a stereo microscope, and a scanning electron microscope revealed that it had morphological features of Pesotum and Sporothix synanarmorphs. Based on the β-tubulin gene sequence analysis, the fungus was identified as the anamorph of Ophiostoma floccosum. Mycological properties of the species including its growth properties on different culture media were described.