• Mycobiology
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• v.44 no.4
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• pp.202-216
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• 2016

Arthonia coreana, Arthonia superpallens, and Arthonia zelkovae are new species from South Korea. All new species are in the Euarthonia tribe, based on the key characteristics of colorless hypothecium and multi-cellular spores. A. coreana has a dull brownish hypophloedal thallus without bleaching and rounded or curved big apothecia in comparison with those of Arthonia punctiformis. A. coreana consistently exhibits 4-septate ascospores, which is a distinctive characteristic that distinguishes it from other Arthonia species. A. superpallens has a white-greenish thallus, pale yellowish apothecia, and a trentepohlioid alga. However, A. superpallens has no distinct prothallus, adnate, and convex apothecia, no pycnidia, and is UV-, in contrast with related species in the Arthonia antillarum group. A. zelkovae has a white, epiphloedal thallus, brownish-black epruinose apothecia covered with a whitish bark layer, and smaller ascospores in comparison with those of A. punctiformis. A. zelkovae consists of a chlorococcoid alga, which differs from related Arthonia species such as A. punctiformis, Arthonia pinastri, and Arthonia glaucella. Although A. zelkovae is similar to Arthonia dispersa in its white-colored thallus, blackish apothecia, and the presence of a chlorococcoid photobiont, A. zelkovae differs from the latter in having larger-sized 3-septate ascospores. Arthonia cinnabarina f. marginata, A. glaucella, Arthonia ilicinella, Arthonia lapidicola, Arthonia leioplacella, Arthonia pertabescens, A. pinastri, Arthonia spadicea, and Arthonia stellaris are newly described in Korea. The diagnostic characteristics of these species are discussed and presented. An artificial key is provided to facilitate identification of Arthonia species from Northeast Asia.

• Mycobiology
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• v.35 no.2
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• pp.87-90
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• 2007

A total of 520 overwintered sclerotia were collected from surface of soil under mulberry trees in six locations in Korea during February in 2006 and 2007. The collected sclerotia were tested for their germination in vitro and identified based on their morphological characteristics. Out of all sclerotia tested, 52.3% of the sclerotia germinated and produced two types of apothecia. The two types of fungi occurred from the sclerotia at the ratio of 49.8 vs. 50.2. The fungal type with cup-shaped apothecia was identified as Ciboria shiraiana and another type of fungus with club-shaped apothecia as Scleromitrula shiraiana. Taxonomy and distribution of the two sclerotial fungi were described and discussed.

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.252-260
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• 1987

Incidence of lettuce drop was observed throughout the growing season in the vinylhouse at the southern part of Korea, Kimhai. Occurrence of this disease was especially severe at the seedling stage. Number of sclerotia in surface soil $(30\times30\times5cm)$ was 22.0 at the seedling stage, and 5.3 at harvest in the infected area. Temperature for mycelial growth ranged from 5 to $30^{\circ}C$ with optimum temperature at $25^{\circ}C$. Sclerotia were formed fewer at low temperature, but their size was larger resulting in heavier dry weight than that at high temperature. The apothecia were formed from the sclerotia that were buried in March, April and September upto 3cm soil depth, but formed from those buried only 1 em soil depth in October. Sclerotia buried in June and December did not form apothecia regardless of soil depth by 90 days. The sclerotia buried in the 5cm of soil depth did not form apothecia. Sclerotia that were embedded in wet or flooded soil at $25^{\circ}C$ and $30^{\circ}C$ for 5 weeks lost their viability. Infection of lettuce was possible with mycelia originated from sclerotia on autoclaved lettuce plant fragments. The fungus was pathogenic on 25 plant species in 8 families in artificial inoculation tests. Lettuce seedlings appeared to be infected by airborne ascospore originated from sclerotia on crops and weeds around paddy fields, because sclerotia existing in soil might perish under long flood conditions during rice cultivation.

• Research in Plant Disease
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• v.13 no.3
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• pp.131-136
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• 2007

Occurrence of popcorn disease on mulberry fruits was surveyed in several locations in Korea from 2005 to 2007. The diseased fruits turned grayish white and changed to hard and black sclerotia during overwintering after falling onto the ground. Apothecia produced from overwintered sclerotia in the fields of mulberry trees were observed in early May. Two types of apothecia were produced from the sclerotia, which were cup-shaped or club-shaped. The fungus with cup-shaped apothecia was identified as Ciboria shiraiana, and that with club-shaped apothecia as Scleromitrula shiraiana. C. shiraiana occurred at the ratio of about 6 vs. 4 in the fields. Occurrence of the disease differed remarkably depending on years, locations, and varieties of mulberry trees investigated. Field survey of the disease incidence showed that Baekhahyeongsang, Dahojosaeng, Hasusang, a native variety and Sawonppong 22 were resistant to the disease, Cheongilppong, Daeseongppong, Guksang 20 and Turkey-D were moderately susceptible, and Cateneo, Moreji and Sanggwa were highly susceptible. Disease incidence in the fields mulched with nonwoven fabrics or plastic films was much lower than that in the non-mulched fields. Disease incidence in the fields mulched with rice straws was similar to that in the non-mulched fields.

• The Plant Pathology Journal
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• v.17 no.4
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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.

• Mycobiology
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• v.48 no.6
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• pp.464-475
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• 2020

Acervus (Pyronemataceae, Pezizales) is a saprobic genus in Pezizomycetes, characterized by colored apothecia, subcylindrical to cylindrical asci and guttulate ascospores. We collected four Acervus samples from China and Thailand. Descriptions and illustrations are introduced for all fresh samples. One new record of A. globulosus from Thailand, one new species, A. rufus, two known species, A. epispartius and A. stipitatus from China are reported. Phylogenetic analysis based on five genes, the large subunit rRNA (LSU), the translation elongation factor-1 alpha (tef1-α), the second largest subunit of RNA polymerase II (rpb2), the largest subunit of RNA polymerase II (rpb1), and the small subunit rRNA (SSU), revealed the distinct position of the new species. The new species is set apart by its red apothecia. A key to Acervus species is also given.

• Mycobiology
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• v.40 no.2
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• pp.91-93
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• 2012

The study introduces the genus Mycobilimbia, from South Korea. M. philippina is reported here as being new to the country. Characteristic features of the species are crustose thallus, globose apothecia, K-proper exciple and hypothecium, Biatora-type asci, 3-septate fusiform ascospores, and a lack of secondary compounds.

• The Korean Journal of Mycology
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• v.10 no.2
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• pp.93-94
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• 1982

Soybean Whetzelinia rot caused by Whetzelinia sclerotiorum was observed in Jinju area. The diseased soybean plants showed withering and sudden collapse under field conditions. Diseased parts exhibited numerous black, irregularly-shaped scleratia embedded in dense white cottonly mycelium on tissue and in the pith of diseased stems. A sclerotium in the moist sand produced several apothecia under laboratary condition. The primary inoculum was supposed to originate from overwintered sclerotia of soil and soybean debris.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.361-368
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• 2009

Cenangium ferruginosum was known as the causal agent of dieback of pines including Pinus koraiensis and Pinus densiflora. Since the first report of the disease in Korea in 1989, a group dying occurred in Seoul, Gyeonggi, Kangwon and Chungbuk in 2007 spring. Although C. ferreginosum was known as a weak pathogen or a parasite, this disease caused in stressed pine by drought, wounding, extremely cold weather or unusual warm winter. In this study, we explained the features of cenangium dieback with the characteristics of pathogen to understand the trend of disease associated with the climatic change of the world. We collected pycnidia and apothecia from the diseased branches and stems of P. koraiensis and P. densiflora in Gyeonggi, Chungcheong and Gyeongsang province to characterization of pathogen. The fungal development on the diseased branches were observed and the isolates from pycnidia and apothecia were identified as Cenangium ferruginosum by their morphological characteristics and the molecular techniques.

• The Plant Pathology Journal
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• v.15 no.4
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• pp.236-241
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• 1999

Sclerotinia twig blight on trees and cottony rot on fruits of Satsuma mandarin were observed in Cheju, Korea in 1996 and 1997. The causal fungus causing citrus twig blight and cottony rot was identified as Sclerotinia sclerotiorum which had cup-shaped apothecia bearing hyaline and clavate asci and periphyses on sclerotium. Symptoms were produced on twigs, developing young leaves, fully developed new leaves, and fruits 2-9 days after wound inoculation, but only on twigs with young lateral buds and developing young leaves by unwound inoculation. The fungus grew well between 10 and $27^{\circ}$, but optimum temperature was $24^{\circ}$ on potato dextrose agar. Most varieties were highly susceptible to S. sclerotiorum, whereas some varieties such as Ichinan were relatively resistant among twelve Satsuma mandarin varieties in the field. This is the first record of Scledrotinia twig blight on trees and cottony rot on stored fruits of Satsuma mandarin in Korea.