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Monochamus alternatus is a very important vector of the pine wood nematode (Bursaphelenchus xylophilus) which is the causal agent of pine wilt disease. To reduce population density of M. alternatus, thiacloprid has been sprayed by aircrafts on pine forests. Thus, we examined the effect of aerial spraying as contact toxicity and thiacloprid residues of pine branches as ingestion toxicity on the mortality of M. alternatus in pine forests in Yangsan, Korea. In addition, the effect of aerial spraying on honey bees, Apis mellifera, was tested in the same locality. Thiacloprid was sprayed once a month from June to August in 2016. To test the effect of thiacloprid, eight M. alternatus and ten honey bees were put into each small mesh cage, which were hung on pine trees in each study plot. Thiacloprid appeared to be effective for reducing longevity of M. alternatus, while mortality and abnormal behaviors were not found for honey bees. In addition, longevity of M. alternatus beetles was declined by thiacloprid residues of pine branches compared to the control group. However, we found that dead pine trees infected by pine wood nematodes in the next year similarly occurred in our study area whether thiacloprid‐aerial spraying occurred or not. Consequently, thiacloprid sprayed by aircraft may be an effective control agent for Monochamus beetle adults without negative effect on honey bees, but aerial application to prevent expansion of pine wilt disease should be reassessed.

Oak tree death caused by symbiosis of an ambrosia beetle, Platypus koryoensis, and an ophiostomatoid filamentous fungus, Raffaelea quercus-mongolicae, has been a nationwide problem in Korea since 2004. In this study, we surveyed the yeast species associated with P. koryoensis to better understand the diversity of fungal associates of the beetle pest. In 2009, a total of 195 yeast isolates were sampled from larvae and adult beetles (female and male) of P. koryoensis in Cheonan, Goyang, and Paju; 8 species were identified by based on their morphological, biochemical and molecular analyses. Meyerozyma guilliermondii and Candida kashinagacola were found to be the two dominant species. Among the 8 species, Candida homilentoma was a newly recorded yeast species in Korea, and thus, its mycological characteristics were described. The P. koryoensis symbiont R. quercusmongolicae did not show extracelluar CM-cellulase, xylanase and avicelase activity that are responsible for degradation of wood structure; however, C. kashinagacola and M. guilliermondii did show the three extracellular enzymatic activities. Extracelluar CM-cellulase activity was also found in Ambrosiozyma sp., C. homilentoma, C. kashinagacola, and Candida sp. Extracelluar pectinase activity was detected in Ambrosiozyma sp., C. homilentoma, Candida sp., and M. guilliermondii. All the 8 yeast species displayed compatible relationships with R. quercus-mongolicae when they were co-cultivated on yeast extract-malt extract plates. Overall, our results demonstrated that P. koryoensis carries the yeast species as a symbiotic fungal associate. This is first report of yeast diversity associated with P. koryoensis.

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.

Korean oak wilt disease caused by Raffaelea quercus-mongolicae is vectored by the ambrosia beetle Platypus koryoensis. To prevent the spread of the disease, the beetle infested oak tree had been cut into logs, covered with plastic vinyl, fumigated with a pesticide, and stored for three years on the site where the tree was cut. This study was carried out to get information on the fungi colonizing the fumigated oak wood. Wood disk samples collected from the fumigated oak logs at two locations in the Taejo Mountain, Cheonan city, were used for fungal isolation. A total of 99 filamentous fungal isolates were obtained from the wood disk samples. Hypocrea spp., Trichoderma spp. and Penicillium spp. were identified based on morphological characteristics and nucleotide sequence analysis of translation elongation factor 1-alpha gene and ITS rDNA region. Trichoderma was the major fungal group. R. quercus-mongolicae, and P. koryoensis were not detected from the fumigated oak wood. Our work provided evidence that after three years of storage, the fumigated oak wilt-diseased logs should be no longer harmful source of oak wilt disease transmission.

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.

The ambrosia beetle, Platypus koryoensis, is a serious pest of oak trees in Korea. In this study we investigated filamentous fungi present in the body of the beetle. Fourteen genera of filamentous fungi belonging to Ascomycota and Basidiomycota were isolated. Among the isolated fungi, some were able to produce wood degrading enzymes. This is first report of fungi associated with P. koryoensis.

Phenylalanine ammonia-lyase (PAL) from the maize pathogen Ustilago maydis was analysed immunologically to obtain insights into the structural relationships between plant PAL and fungal PAL and between PAL and histidine ammonia-lyase (HAL). Cross-reactivity was found among all the PAL proteins from different species tested, using antibodies raised against both plant and fungal PALs. Both anti-Alfalfa and anti-popular PAL antibodies strongly recognized plant PALs but only weakly recognized fungal PALs. Antibodies raised against U. maydis PAL only weakly recognized the Rhodotorula glutinis yeast PAL. The anti-U. maydis PAL antibodies showed low affinity for the plant PALs but they bound strongly to Pseudomonas bacterial HAL. Significant cross-reactivity between the two plant PAL antibodies and the bacterial HAL was also observed. Both the anti-Ustilago PAL and the anti-poplar PAL antibodies displayed similar enzyme inhibition patterns, including moderate inhibition of bacterial HAL activity. However, the bacterial HAL antibody inhibited only Ustilago PAL. The PAL and HAL antibodies tested showed no inhibition against yeast PAL. This is first report on the immunological relationships between PAL and HAL.

The production of dihydroxynaphthalene (DHN) melanin is known to be essential factor for pathogenicity in Colletotrichum lagenarium. However, the genetic diversity of melanin genes was not much known among Colletotrichum spp. To investigate the variability of melanin gene in Colletotrichum spp. that cause anthracnose on diverse crops including tomato, we cloned and sequenced partial sd, one of DHN melanin genes encoding for scytalone dehydratase, from eight strains of C. coccodes, C. acutatum, C. truncatum C. caricae, and C. musae. The size of PCR-amplified sd ranged 437 bp to 545 bp. The nucleotide sequence identity of sd among the Colletotrichum strains tested varied from 49% to 99%. All of the PCR-amplified sd from eight strains contain an intron and have two exons coding for 122 amino acids. Overall, the size and nucleotide sequence of sd varied among the five Colletotrichum spp. Sequence identity of the predicted scytalone dehydratase protein of 122 amino acids ranged 50 to 99%. Phylogentic analysis based on the sd nucleotide sequences revealed that the five Colletotrichum spp. could be genetically divided.

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.

Notes on Three Species of the Genus Euphoriomyces (Laboulbeniales) from KoreaTaxonomic Studies on Myelochroa from KoreaMolecular Analysis of Korean Anzia opuntiella (Lichenized Ascomycota) Based on...

Pine tree death caused by pine wood nematode (PWN) involves phoretic relationships between PWN and its vector Japanese pine sawyer beetle (JPS). In an effort to understand the diversity of fungi involved in PWN life cycle, a total of 176 fungal isolates were collected from PWNs, adults and larvae of JPS, PWN-diseased Japanese black pine that was cut down in 2005 at Jinju, Korea. Based on microscopic observation and colony morphology, and sequence analysis of the ITS rDNA, the fungal isolates were identified at the level of genus. Three genera including Mucor, Ophiostoma, and Penicillium were identified from PWN. Two genera of Ophiostoma and Penicillium were discovered from JPS larvae. From JPS adult beetles, nine genera of Aspergillus, Gibberella, Hypocrea, Irpex, Leptosphaeria, Ophiostoma, Penicillium, and Plectosphaerella and unknown basidiomycetes were found. Ten genera from PWN-infected wood were confirmed as Bionectria, Botrytis, Camarops, Fusarium, Hypocrea, Nectrtia, Mucor, Ophiostoma, Penicillium, and Trichoderma. Penicillium and Ophiostoma were commonly distributed on PWN and its vector and host. This is first report of the fungi associated with PWN and its vector and host 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.

We isolated and identified a strain of Eurotium rubrum from Meju that has not been reported in Korea. This fungus is yellowish brown; reverse dark brown on CYA and PDA while yellow on 2% MEA at 25℃. Cleistothecia are first bright yellow and gradually turned brown. Mycerial growth on CYA attained a diameter of 30 mm at 20℃, 37 mm at 25℃ and 32 mm at 30℃ after 15 days. The isolate grew slower on 2% MEA (< 20 mm 15 days at 25℃) compared to CYA and PDA (< 40 mm 15 days at 25℃). Cleistothecia are superficial, yellow to light brown, globose to subglobose, 40~75 µm in diameter. Asci are 8-spored and globose to subglobose 8~11 µm. Ascospores are disciform, 4.0~5.0 µm in length and 4.2~4.5 µm in width. Conidia are ovate or bacillar, finely roughened to densely spinulose, 4.6~6.0 µm in length and 3.0~4.3 µm in width. Compared to known Eurotium rubrum, the Korean isolate showed 99% sequence similarity in ITS rDNA (554 bp) and calmodulin (750 bp) gene and 100% in β-tubulin (1016 bp) gene. The E. rubrum isolate also had weak β-glucosidase and protease activities.

To evaluate which dye is effective in a plate assay for detecting extracellular cellulase activity produced by fungi, four chromogenic dyes including remazol brilliant blue, phenol red, congo red, and tryphan blue, were compared using chromagenic media. For the comparison, 19 fungal species belonging to three phyla, ascomycota, basidiomycota, and zygomycota were inoculated onto yeast nitrogen-based media containing different carbon substrates such as cellulose (carboxylmethyl and avicel types) and cellobiose labeled with each of the four dyes. Overall, the formation of clear zone on agar media resulting from the degradation of the substrates by the enzymes secreted from the test fungi was most apparent with media containing congo red. The detection frequency of cellulase activity was also most high on congo red-supplemented media. The results of this study showed that congo red is better dye than other three dyes in a plate assay for fungal enzyme detection.