• 한국식물병리학회지
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• 제11권3호
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• pp.230-237
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• 1995

Airborne and waterborne ascospores and conidia of Botryosphaeria dothidea were collected in apple orchards at Suwon and Chunan in 1992 through 1994. Both waterborne and airborne spores were first detected in mid April to early May. Thereafter, spores were abundant in early June to late August and present until early December. Rainwater collections contained much more conidia than ascospores during the apple growing seasons. Airborne ascospores catches, which were also detected on humid days without measurable rainfall, were much more than airborne conidia catches. High amounts of ascospores were detected in early times of apple growing season, whereas most conidia catches occurred in later times of the season. The number of waterborne conidia and airborne ascospores was positively correlated with mean daily maximum, minimum, and average air temperatures during the trapping periods (p=0.01). However, no significant correlation was found between the number of spores and the total precipitation during the trapping periods.

• The Plant Pathology Journal
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• 제27권2호
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• pp.138-147
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• 2011

Xylogone ganodermophthora, an ascomycetous fungus, is known to cause yellow rot in the cultivated mushroom Ganoderma lucidum. In this study, we investigated the dissemination of this fungal pathogen in G. lucidum grown in cultivation houses. To determine the role of ascospores produced by X. ganodermophthora in disease development, we constructed a green fluorescent protein-labeled transgenic strain. This X. ganodermophthora strain produced a number of ascomata in the tissues of oak logs on which G. lucidum had been grown and on the mushroom fruit bodies. However, the ascospores released from the ascomata were not able to germinate on water agar or potato dextrose agar. Moreover, less than 0.1% of the ascospores showed green fluorescence, indicating that most ascospores of X. ganodermophthora were not viable. To determine the manner in which X. ganodermophthora disseminates, diseased oak logs were either buried in isolated soil beds as soil-borne inocula or placed around soil beds as air-borne inocula. In addition, culture bottles in which G. lucidum mycelia had been grown were placed on each floor of a five-floor shelf near X. ganodermophthora inocula. One year after cultivation, yellow rot occurred in almost all of the oak logs in the soil beds, including those in beds without soil-borne inocula. In contrast, none of the G. lucidum in the culture bottles was infected, suggesting that dissemination of X. ganodermophthora can occur via the cultivation soil.

• 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.

• Mycobiology
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• 제40권3호
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• pp.147-150
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• 2012

This paper provides a description of Opegrapha herbarum, Opegrapha viridis and Phaeographis subdividens, all newly identified in the Republic of Korea. The characteristic features of O. herbarum include Varia-type asci, Subelevata-type ascospores, a lack of secondary metabolites and a saxicolous habitat. O. viridis possesses Calcarea-type asci, Vulgata-type ascospores and no chemicals in the thallus. P. subdividens is recognizable by its curved to sinuous lirellae, divergent labia, a brown and uniformly thick proper exciple which is open at its base, 3~4-septate ascospores, and lack of secondary metabolites. All three taxa are now reported to exist on Bogil Island in the Republic of Korea.

• Mycobiology
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• 제48권6호
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• pp.443-449
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• 2020

Two new species, Thelopsis ullungdoensis and Phylloblastia gyeongsangbukensis are described from Ullung-Do (Island), South Korea. The closest relatives from Europe and Korea are epiphytic Thelopsis flaveola which differs by their immersed or semi-immersed yellow ascomata, ascospores without halo and their habitat of smooth bark (mainly Fagus) in humid and cold climates. Thelopsis gangwondoensis differs by its bigger semi-immersed ascomata (600-700 ㎛ in diam.), oblong halonate ascospores (8-12 × 6-8 ㎛) and its habitat of smooth bark of deciduous trees. P. gyeongsangbukensis differs from its relatives within the genus in having 5-septate ascospores (22-26 × 6-8 ㎛), semi-immersed, subglobose ascomata with a flattened top (250-400 ㎛) and a thin, matt, uneven gray-brown to gray-green continuous thallus without isidia.

• Mycobiology
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• 제28권1호
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• pp.5-10
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• 2000

The genus Hypoxylon is a member of the Xylariaceae which has brown to dark brown and pha- seoliform single cell ascospores with a conspicuous full germ slit. The isolates of Hypoxylon collected from England, Hong Kong and Korea are compared with similar taxa and described. These isolations under Hypoxylon section are detailed and illustrated, using light microscopy and scanning electron microscopy. Hypoxylon howeianum and H. rubiginosum are described and compared with former collection from Korea. A key to the species is also included.

• 식물병연구
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• 제7권1호
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• pp.16-19
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• 2001

최근 박과류 재배 주산단지에서 발생이 증가하고 있는 검은점뿌리썩음병 병원균의 균학적 특성과 발병 포장에서의 병원균 밀도를 조사하였다. Monosporascus cannonballus의 균사생장과 자낭각의 형성은 PDA배지에서 가장 좋았고, CMA와 OMA, V-8 juiceqowl에서는 비슷한 생장량을 보였으나, WA에서는 생장도 빈약하였고 자낭각은 전혀 형성되지 않았다. 자낭각의 형성 적온은 25~3$0^{\circ}C$였다. 이병포장에서 검은점뿌리썩음병균의 자낭포자는 토양 20g당 1.7~14.6개 범위로 존재하였다. 토양심도별로는 10cm나 30cm보다 20cm 깊이에 보다 많이 분포하는 경향이었으나 조사포장간에 편차가 심하였다.

• 한국식품과학회지
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• 제19권1호
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• pp.38-41
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• 1987

팽창된 복숭아 통조림으로부터 분리된 Saccharomyces cerevisiae Py9와 Saccharomyces chevalieri Pw7의 자낭포자의 열저항성을 측정하였다. 그 결과 S. cerevisiae Py9는 $D_{58}$=6.5분, $D_{60}$=2.5분, $D_{62}$=1.25분이었고 Z값은$5.5^{\circ}C$로 나타났다. 그리고 S. chevalieri Pw7은 $D_{58}$=35분, $D_{60}$=3.5분, $D_{62}$=1.5분이었고 Z값은 $3.4^{\circ}C$로 나타났다. 열처리를 했을때 미생물 사멸이 직선인 부분과 그렇지 않은 부분으로 나뉘어지므로 즉, tailing 현상으로 인해 가열치사속도곡선과 가열치사시간곡선에 나타난 대로의 열처리 만으로는 효모의 완전 살균이 불가능함을 알 수 있었다.

• The Plant Pathology Journal
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• 제17권4호
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• pp.216-221
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• 2001

Dieback of pine branches or twigs with brown needles occurs most commonly on Pinus species after severe winter in Korea. In this study, Cenangium ferruginosum was isolated from infected stems, branches, and twigs of Pinus koraiensis (C1), P. densiflora (C2), and P. thunbergii (C3). Morphological and cultural characteristics of the isolates were than compared. There were no significant differences in the morphological characteristics of conidia and ascospores produced by the three isolates. However, cultural differences were observed among the isolates. Optimum temperatures for mycelial growth of C1, C2, and C3 were 15, 20, and $20^{\circ}$, respectively. C1 produced a few conidia and no ascospores, while C2 and C3 produced abundant ascospores and conidia. While optimum temperatures for mycelial growth ranged from 15 to $20^{\circ}$, mycelial growth was also relatively good at lower temperatures of 5-$10^{\circ}$. Conidiomata and conidia were produced on MSA (malt extract soya peptone agar) after 25-30 days of incubation in the dark at $15^{\circ}$. Apothecia were produced by altering culture condition from 15 to $20^{\circ}$, and incubating for 35-60 more days. Optimum temperature for ascospore and conidium germination was $20^{\circ}$. RAPD analysis revealed that there was high similarity of 0.78 between C2 and C3, and low similarity of 0.31 between C2 or C3 and C1.

• 한국식물병리학회지
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• 제11권4호
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• pp.344-347
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• 1995

Factors affecting on the ascospore release of Mycosphaerella nawae, the causal organism of persimmon leaf casting disease, were investigated. The ascospore release of the pathogen occurred following the precipitation of rain. The ascospore release started from the beginning of raining, reached maximum at 2 hours after the precipitation of rain, and then decreased abruptly. When the inoculum source (a file of infected leaves) was submerged in water to imitate raining conditions, 92.5% of the total ascospores were released within 1 hour after submerging, 5.8% were after 2 hours, 1.4% were after 4 hours, 0.1% were after 8 hours, and none detected after 10 hours. The inoculum source overwintered in the field released ascospores much more and earlier than the inoculum source kept in the greenhouse. The first ascospore release was about 10 days earlier, and the amount of the total liberated spores was 3∼4 times higher in the field inoculum source than the greenhouse nioculum source. The early defoliated leaves (in early October) in the previous year produced ascospores twice more than the late defoliated leaves (in early November) produced.