• 한국식물병리학회지
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• 제13권4호
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• pp.215-218
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• 1997

감나무 둥근무늬낙엽병 이병엽에서의 이듬해 봄 위자낭락 성숙에 영향을 미치는 환경요인에 대한 검토를 하였다. 월동 후 이병엽에서 위자낭각이 완전히 성숙되는 시기는 대체로 4월 하순이었는데 이때의 평균 기온은 $14^{\circ}C$ 정도였고 충분한 강우가 있을 때였다. 낙엽시기에 따른 성숙 정도는 10월 초에 낙엽된 이병엽이 11월 초 낙엽된 이병엽보다 성숙율은 상당히 높았으나 성숙시기에는 차이가 없었다. 월동장소에 따른 차이는 야외에서 월동된 이병엽은 온실에서 보관되었다가 이듬 봄에 야외에 노출한 것보다 성숙시기가 20일 정도 빨랐고 성숙율도 훨씬 높았다. 그리고 분생포자를 인공접종하여 발병된 이병엽에서도 위자낭각이 다수 형성되었고 이듬해 봄 성숙율도 자낭포자의 자연감염에 의한 병반에서와 큰 차이가 없었다.

• 한국식물병리학회지
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• 제14권5호
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• pp.408-412
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• 1998

In order to illustrate the role of conidia of Mycosphaerella nawae as a secondary inoculum in nature, pseudothecial development on persimmon leaves was investigated microscopically. The fungal ascospores have been believed as the primary or only inoculum source in nature, however, pseudothecia were readily formed on persimmon leaves infected naturally and artificially by conidia. The pseudothecia of M. nawae were found to form in the tissues of infected leaves while the leaves were still hanging on the trees. The size of pseudothecia were approximately 51.0~122.4$\times$51.0~112.2 ${\mu}{\textrm}{m}$ (82.8 $\times$72.5 ${\mu}{\textrm}{m}$in average), the shapes were spherical, ovoid or occidental pear type. The sizes of asci were approximately 30.6~61.2$\times$8.2~10.2 ${\mu}{\textrm}{m}$(46.6$\times$9.4 ${\mu}{\textrm}{m}$ in average) and the shapes were cylinder or banana. The ascospores were mostly spindle type, and the sizes were 10.2~12.2$\times$3.1~4.1 ${\mu}{\textrm}{m}$ (11.4$\times$3.2 ${\mu}{\textrm}{m}$ in average)-like. The pseudothecial formation was initiated before defoliation and morphological characteristics of the pseudothecia, ascus and ascospores on the infected leaves were fully illustrated in this study. Results indicated that conidia of M. nawae induce circular leaf spot of persimmon as much as ascospores, and might play an important role of the disease epidemics in nature.

• 한국균학회지
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• 제26권2호통권85호
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• pp.287-292
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• 1998

율무 잎마름병을 일으키는 Bipolaris coicis의 완전세대를 배양기내에서 형성하도록 유도하였다. 국내 17개 지역에서 1994년부터 1996년까지 89개의 균주를 수집하였다. 이들을 $25^{\circ}C$에서 볏짚을 위에 올려놓은 Sach's nutrient agar 배지에서 대치배양하였다. 위자낭각은 특정 친화적인 균주의 조합일 때만 형성되었다. 위자낭각은 대체로 배양 2주 후에 볏짚 위에 형성되었으나, 일부 위자낭각에서만 자낭과 자낭포자가 관찰되었다. 위자낭각은 흑색이며 구형이었고, 돌출한 ostiolar beak을 가지고 있었다. 그 내부는 무색이고, 사상형민 위측사로 채워져 있었다. 자낭은 원통형내지 곤봉형이었고, 직선형이거나 약간 굽은 것도 있었다. 자낭벽은 이중격막으로 둘러싸여 있었고 짧은 stipe가 있었다. 자낭포자는 사상형이고 무색이었으며, 자낭의 장축과 평행하거나 약간 나선형으로 굽어 있었다. 자낭포자의 크기는 $146-166.4{\times}2.6-3.8\;{\mu}m$이었다. 이러한 형태적 특징에 기초하여 이 곰팡이의 완전세대는 Cochliobolus nisikadoi (Tsuda, Ueyama & Nishihara Alcorn)으로 동정되었다.

• 미생물학회지
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• 제20권2호
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• pp.80-88
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• 1982

한국의 두장소의 논토양에서 회석평판법에 의하여 토양균을 분리하였다. 동정된 30종중 14종은 한국에서 미기록종이며 이중 7종은 자낭균류에 속하는 것으로 본 논문에 서술하였다. Talaromyces의 종중에서는 Talaromyces flavus var. flavus, T. panasenkoi, T. stipitauts 그리고 T. trachyspermus가 가장 우세하게 분포되어 있다. 또 특이한 것은 Westerdykella multispora가 현저하게 주목된다. Westerdykella multispora는 많은 격막이 있는 원통형 자낭포자가 32개 포함된 자낭을 가지고 있는 구형 또는 아구형의 pseudothecia를 형성한다. Chaelomium globosum은 cellulose를 분해하는 ascomycetes의 종류로 많은 파상 정모와 ostiole을 가지고 있는 검은 자낭각을 형성한다. 이 자낭각은 레몬형태의 올리브색을 띤 갈색자낭포자 8개를 포함하고 있는 곤봉모양을 하고 있으며 소실성의 자낭을 형성한다. 또 다른 Ascomycete로써 Acremonium an-amorph를 가지고 있는 Emericellopsis terricola로 2곳의 채취장소에서 분리할 수 있었다.

• The Plant Pathology Journal
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• 제17권6호
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• pp.347-349
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• 2001

Black blights attacked the blossom and flower buds of wild chrysanthemum (Chrysanthemum boreale) in the experimental field in Hamyang in 1998. The infection rate of the disease on the plant ranged from 4.0 to 91.8%. The pathogen isolated from the infected flower buds produced numerous conidia in pycnidia. The pycnidia, which were immersed into the petals, emerged through the epidermis by short ostiolate neck. Conidia had 0-3 septate (mostly uniseptate) and were 10-27.5 $\times$5-7.5 ㎛ in size. The fungus produced pseudothecia on potato dextrose agar (PDA), and uniseptate ascospores produced in asci were 10$\times$2.7 ㎛ in size. The pathogen also produced pycnidia and pycnidiospores on PDA after 4 weeks in the dark condition. The conidia produced on PDA were smaller than those from infected plants. Based on the examined mycological characteristics, the fungus was identified as Didymella chrsanthemi.

• Mycobiology
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• 제44권4호
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• pp.191-201
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• 2016

In this study, the phylogeny and morphology of Mycosphaerella nawae (Dothideomycetes, Ascomycota) were examined using Korean and Japanese isolates, to establish the phylogenetic relationship between M. nawae and its allied species. Korean and Japanese isolates of M. nawae were collected from circular leaf spot-diseased leaves and were confirmed based on internal transcribed spacer (ITS) sequence data. Phylogenetic analysis was conducted using multiple genes, including the ITS region, 28S rDNA, ${\beta}-tubulin$, translation elongation $factor-1{\alpha}$, and actin genes. Our results revealed that M. nawae is closely related to members of the genus Phaeophleospora but are distant from the Ramularia spp. In addition, microscopic analysis revealed pseudothecia on the adaxial and abaxial surface of overwintered diseased leaves (ODL) and only on the abaxial surface of diseased leaves. Ascospores are oval to fusiform, one-septate, tapered at both ends, $1.7{\sim}3.1{\times}8.1{\sim}14.1{\mu}m$, and were observed in ODL. Conidia are oval, guttulate, one-septate, $3.5{\sim}4.9{\times}12.8{\sim}19.8{\mu}m$, and barely discernable on 30-day cultures. To our knowledge, this is the first report on the phylogeny of M. nawae, which is closely related to the genus Phaeophleospora, especially P. scytalidii.

• 한국균학회지
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• 제51권4호
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• pp.277-286
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• 2023

Tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease in wheat worldwide. In April 2021, tan spot symptoms were observed in a commercial wheat field in Suncheon, Jeonnam Province, Korea, with over 5% of the wheat leaves exhibiting symptoms. These symptoms included oval-shaped tan necrosis surrounded by a bright halo. The three representative isolates exhibited irregular mycelial growth on V8-potato dextrose agar and produced pseudothecia. Based on the concatenated sequence datasets of four multi-genes, including the internal transcribed spacer, large subunit ribosomal RNA, glyceraldehyde-3-phosphate dehydrogenase, and RNA polymerase II second-largest subunit genes, phylogenetic analysis revealed that these three isolates clustered in the same clade as P. tritici-repentis. Results of pathogenicity test indicated that the initial symptoms appeared 5 days post-inoculation (dpi), with typical tan spot symptoms developing at 7 dpi. The pathogen was successfully re-isolated from the symptomatic tissues, thus fulfilling Koch's postulates. Furthermore, we selected three fungicides that effectively inhibited the mycelial growth of P. tritici-repentis by more than 90% in vitro. To the best of our knowledge, this is the first report of tan spot disease in wheat in Korea.