• Mycobiology
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• v.43 no.1
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• pp.81-86
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• 2015

To promote the selection of promising monokaryotic strains of button mushroom (Agaricus bisporus) during breeding, 61 progeny strains derived from basidiospores of two different lines of dikaryotic parental strains, ASI1038 and ASI1346, were analyzed by nucleotide sequencing of the intergenic spacer I (IGS I) region in their rDNA and by extracellular enzyme assays. Nineteen different sizes of IGS I, which ranged from 1,301 to 1,348 bp, were present among twenty ASI1346-derived progeny strains, while 15 different sizes of IGS I, which ranged from 700 to 1,347 bp, were present among twenty ASI1038-derived progeny strains. Phylogenetic analysis of the IGS sequences revealed that different clades were present in both the ASI10388- and ASI1346-derived progeny strains. Plating assays of seven kinds of extracellular enzymes (${\beta}$-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease) also revealed apparent variation in the ability to produce extracellular enzymes among the 40 tested progeny strains from both parental A. bisporus strains. Overall, this study demonstrates that characterization of IGS I regions and extracellular enzymes is useful for the assessment of the substrate-degrading ability and heterogenicity of A. bisporus monokaryotic strains.

• Mycobiology
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• v.38 no.4
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• pp.249-255
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• 2010

We identified Lacrymaria velutina of the Coprinaceae in Korea. The unusually large and sturdy fruiting body, fibrillose to fibrillose-scaly cap and stalk without a volva with an obscure superior hairy ring zone or hairy annulus, and blackish brown, warted spores distinguished this species from closely related Psathyrella species. An illustrated account of the microscopic traits is presented. Fruiting bodies with obtusely hemispherical caps, 2.5~6 cm, becoming convex with age; surface dry, densely fibrillose-scaly with split margin; stipe, 4.5~6 cm, equal, hollow, fibrillose, dry, whitish above the superior ring zone, light brown below; crowded gills, adnexed, dark black at maturity. Pileipellis typically cellular with the gill edge appearing white and beaded. Blackish brown basidiospores that discolor in concentrated sulfuric acid. Spores elliptical, warted, $9\sim11{\times}6\sim8{\mu}m$, with prominent snout-like germpores. Cheilocystidia abundant, $57\sim68{\times}19\sim25{\mu}m$, and narrowly elongated clavate, often clustered in threes or fours. Pleurocystidia rarely present, $45\sim47.5{\times}12\sim13{\mu}m$, and clavate to utriform. This trait distinguishes our sample as L. velutina from other Psathyrella spp. of the Coprinaceae, which have smooth spores. This taxon was clarified by the observation that Psathyrella spores fade in concentrated sulfuric acid. A molecular phylogenetic study revealed that our specimen was Lacrymria velutipes, which is closely related to Lacrymaria lacrymabunda. Moreover, those two species are clearly distinguishable from other Psathyrella species, which agreed with the morphologically distinctive traits described above. We believe that this is the first report of this taxon, which has not been described in Korea.

• Research in Plant Disease
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• v.9 no.4
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• pp.209-212
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• 2003

Blister blight was occurred on tea (Thea sinensis) in a farmer's tea garden located in Sicheon-myon, Sancheong-gun, Gyeongnam province, Korea. The typical symptoms of the disease were appeared on the leaves and bud. The early symptom were started with small yellowish spots then infected area became upheave and covered with white blister which the hymenium de.veloped from under neath of epidermis. Generally, the infected leaves and buds were appeared like rice cake. Colonies formed on PDA were developed white, later turned milk white. Basidia were 2 sterigma, and 30${\sim}$53 ${\times}$ 3.1${\sim}$5.8 ${\mu}m$ in size. Basidiospores were ellipsoid curved, coloriess, 1-celled and 11${\sim}$14.7 ${\times}$ 4${\sim}$5.4 ${\mu}m$ in size. The optimum temperature for growth of the fungus was about $25^{\circ}C$ on PDA and PSA. This is the first report on the blister blight of tea caused by Exobasidium vexans in Korea.

• Research in Plant Disease
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• v.12 no.3
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• pp.284-286
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• 2006

Leaf gall was occurred on Rhododendron indicum(L.) Sweet[=Azalea indica L.] in a farmer's garden located in Geumsan-myon, and along the walk way of Gangju pond in Jeongchon-myon, Jinju, Korea. The infected leaves was deformed into very conspicuous, pale, fleshy shapeless galls. Basidia were fusiform, $3{\sim}5$ sterigma, and $8{\sim}35{\times}3{\sim}6{\mu}m$ in size. Basidiospores were musiform, straight or curved and $10{\sim}22{\times}3{\sim}5{\mu}m$ in size. The causal organism was identified as Exobasidium japonicum Shirai based on the mycological characteristics of the fungus and pathogenicity. This is the first report on the leaf gall of R. indicum caused by E. japonicum in Korea.

• Mycobiology
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• v.47 no.4
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• pp.368-377
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• 2019

The genus Macrolepiota (Agaricales, Basidiomycota) is easy to recognize at the genus level because of big, fleshy basidiocarps with squamules covering the pileus; a single or double annulus; and big, thick-walled basidiospores with a germ pore. However, morphological identification is often unreliable in Macrolepiota due to similar morphological features among species. Due to the uncertainty of previous morphological identification in the genus Macrolepiota, it is necessary to re-examine Korean Macrolepiota using molecular data. We reexamined 34 Macrolepiota specimens collected from 2012 to 2018 in Korea using a reverse taxonomic approach, whereby species identification was first done based on the internal transcribed spacer (ITS) region analysis, followed by morphological confirmation. We identified the presence of four species: M. detersa, M. mastoidea, M. procera, and M. umbonata sp. nov. Two species (M. detersa and M. mastoidea) were previously unrecorded from Korea and M. umbonata is a new species. Detailed descriptions of all four species and taxonomic key are provided in this study. Macrolepiota procera and M. umbonata are distributed through the country, but M. detersa and M. mastoidea are distributed only in limited areas. According to our results, the combination of ITS locus and morphology proved to be a robust approach to evaluate the taxonomic status of Macrolepiota species in Korea. Additional surveys are needed to verify the species diversity and clarify their geographic distribution.

• Korean Journal Plant Pathology
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• v.10 no.4
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• pp.261-269
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• 1994

One hundred and ninety two isolates of Armillaria were obtained from mycelial fans on infected hosts, rhizomorphs, and single basidiospores or trauma tissue of fruiting bodies. Mating tests showed that two of these isolates were A. mellea, eight were A. tabescens, 20 were A. ostoyae, and 162 were A. gallica. Armillaria ostoyae was mainly isolated from Pinus koraiensis and Qurecus spp., A. tabescens from fruiting bodies on Pinus densiflora and Qurecus spp., and A. gallica from many tree species but not Pinus koraiensis. Armillaria mellea, A. gallica, A. ostoyae and A. tabescens showed distinct protein banding patterns. Mycelial growth and rhizomorph formation was good on basal medium with ethanol added. A. gallica and A. mellea formed many rhizomorphs, but A. ostoyae did not. A. gallica showed the best rhizomorph formation on media with tannic acid and ethanol, but a. mellea formed the most rhizomorphs on gallic acid. Rhizomorphs showed monopodial branching for A. gallica and dichotomous branching for A. ostoyae. Fruiting bodies. formed in the laboratory on sawdust media most abundantly by A. tabescens. In nature, fruit body formation by A. tabescens was from early to mid August. A. ostoyae and A. gallica fruit bodies were formed from early August to late October. While there are common names in Korea for A. mellea and A. tabescens, such as mulberry mushroom relative, no common names are available for A. gallica and A. ostoyae. Therefore, we refer to a. gallica as the Gastrodia mushroom because it has been used to produce Gastrodia and A. ostoyae as the Korean pine mushroom because it is frequently found as mushrooms on Korean pine.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.34-38
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• 2006

To assess the effects of proton beam on radiation sensitivity of the basidiospore and mycelium of oyster mushroom (Pleurotus ostreatus), the $D_{10}$ values and $L_{50}$ (lethal 50%) values were analysed. By the proton beam radiation, the survival rate and germination rates increased at the dose of $10\;Gy{\sim}100\;Gy$ and then decreased significantly over 500 Gy. $L_{50}$ values of basidiospore and mycelium of Pleurotus ostreatus were over 500 Gy and 400 Gy, respectively. $D_{10}$ values were calculated from linear regression formulae ($D_{10}\;=\;-1/slope(b)$, y = a + bx) as 750 Gy and 1,250 Gy, respectively. Based on our experiment, the optimum dose of proton beam as a mutation source would be between from 500 Gy to 750 Gy for basidiospores and from 400 Gy to 1000 Gy for mycelium of oyster mushroom.

• Mycobiology
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• v.48 no.4
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• pp.288-295
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• 2020

Species of Laccaria (Hydnangiaceae, Agaricales, and Basidiomycota) are well-known ectomycorrhizal symbionts of a broad range of hosts. Laccaria species are characterized by brown, orange, or purple colored basidiocarps, and globose or oblong, echinulate and multinucleate basidiospores. While some Laccaria species are easily identified at the species level using only the morphological characteristics, others are hard to distinguish at the species level due to small differences in morphology. Heretofore, ten Laccaria species have been reported in Korea. While studying the fungal diversity in the National Parks of Korea, two new Laccaria species were discovered. Species identification was done based on molecular analyses (ITS, 28S rDNA, rpb2, and tef1), then were confirmed by their corresponding morphologies. The two newly discovered Laccaria species are proposed here as Laccaria macrobasidia and Laccaria griseolilacina. The unique morphological characters of L. macrobasidia that distinguish it from its closely related species are orange-brown colored basidiocarp, long basidia and the absence of cheilocystidia. L. griseolilacina is characterized by a light grayish lavender-colored pileus and the absence of cheilocystidia. Two new species are described and illustrated in the present paper.

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.164-169
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• 1984

Interspecific heterokaryons were obtained between auxotrophic mutants of Pleurotus ostreatus and Pleurotus florida by polyethylene $glycol-Ca^{++}$ induced fusion of somatic protoplasts. The fusion products produced colonies of dense growing mycelium after 10-14 days culture on hypertonic Mushroom Minimal Medium. When they were transferred to Mushroom Minimal Medium plates, the sectors showed normal vegetative morphology but the colonies of irregular shape varied in growth rate. All of the colonies produced fruit body of normal pilei. Some heterokaryon colonies bearing none or only a small amounts of basidiospores were isolated. Fusion products, generally, gave higher basidiocarp yields than the parents.

• The Korean Journal of Mycology
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• v.17 no.4
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• pp.189-193
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• 1989

Ganoderma lucidum formed uniquely non-basidiocarpous basidiospore (NBB) from the aerial mycelia on agar media without the normal basidiocarps. Light was necessary for NBB formation. Best sporulation was obtained at the periodic exposure of 16 hour light and 8 hour darkness for more than 8 days. Effective wave length was blue and yellow but non sporulation was induced by near U.V. light. Effective light intensity for NBB bearing appeared to be about 1,000 Lux as white light. Photomorphogenetic responses in Ganoderma lucidum were clearly different among strains of the fungus.