• The Plant Pathology Journal
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• v.37 no.4
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• pp.329-338
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• 2021

Alternaria leaf blight is one of the most common diseases in watermelon worldwide. In Korea, however, the Alternaria species causing the watermelon leaf blight have not been investigated thoroughly. A total of 16 Alternaria isolates was recovered from diseased watermelon leaves with leaf blight symptoms, which were collected from 14 fields in Korea. Analysis of internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and RNA polymerase II second largest subunit (RPB2) were not competent to differentiate the Alternaria isolates. On the contrary, analysis of amplicon size of the histone H3 (HIS3) gene successfully differentiated the isolates into three Alternaria subgroups, and further sequence analysis of them identified three Alternaria spp. Alternaria tenuissima, A. gaisen, and A. alternata. Representative Alternaria isolates from three species induced dark brown leaf spot lesions on detached watermelon leaves, indicating that A. tenuissima, A. gaisen, and A. alternata are all causal agents of Alternaria leaf blight. Our results indicate that the Alternaria species associated watermelon leaf blight in Korea is more complex than reported previously. This is the first report regarding the population structure of Alternaria species causing watermelon leaf blight in Korea.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.227-238
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• 2012

Mitogen-activated protein kinase (MAPK) cascades are conserved signaling modules in the eukaryotic cells. They are involved in many major cell processes in fungi such as stress responses, vegetative growth, pathogenicity, secondary metabolism and cell wall integrity. In this review, we summarized the advances of research on the MAPK signaling pathways in Alternaria species. As major phytopathogenic fungi, Alternaria species reduce crop production. In contrast to the five MAPK pathways known in yeast, only three MAPK pathways as Fus3/Kss1-type, Hog1-type, and Slt2-type have been characterized in Alternaria. The Fus3/Kss1-type MAPK pathway participates in regulation of vegetative growth, conidiation, production of some cell-wall-degrading enzymes and pathogenicity. The Hog1-type pathway is involved in osmotic and oxidative stress, fungicides susceptibility and pathogenicity. The Slt2-type MAP kinases play an important role on maintaining cell wall integrity, pathogenicity and conidiation. Although recent advances on the MAPK pathways in Alternaria spp. reveal many important features on the pathogenicity, there are many unsolved problems regarding to the unknown MAP kinase cascade components and network among other major signal transduction. Considering the economic loss induced by Alternaria spp., more researches on the MAPK pathways will need to control the Alternaria diseases.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.151-157
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• 1995

국내에서 분리한 20종의 Alternaria 277개 균주를 사용하여 Alternaria 진균소독인 altenuene(ALT), altertoxin-I(ATX-I) 및 tenuazonic acid(TA)의 in vitro에서의 생성능과 그 분포를 조사하였다. 각 사용균주를 200g의 살균된 쌀배지에 접종하여 $25^{\circ}C$에서 3주간 배양하였다. Alternaria 배양체들을 methanol로 추출하고 용매분획과 TLC 및 HPLC분석을 통하여 순화하였다. A. alternata와 그와 형태적으로 유사한 A. kikuchiana, A. longipes 및 A. mail는 비록 종간 및 종내의 균주간에 생성량의 차이는 매우 다양하였지만 TA를 비롯한 5종의 진균독소를 모두 생성하였다. A sesami와 A. sesamicola는 4종의 진균독소(AOH, AME, ALT, ATX-I)를 생성하였고 A. cucumerina, A. dauci, A. macrospora, A. porri, A. solani, A. tagetica와 A. zinniae와 같은 대형분생포자와 긴 beak를 형성하는 7종의 Alternaria균들은 AOH와 AME만을 생성하였다. A. brassicicola, A. helianthi, A. panax, A. radicina 및 A. raphani등 5종의 Alternaria는 5종의 진균 독소를 모두 생성하지 않았다.

• Mycobiology
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• v.29 no.1
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• pp.27-42
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• 2001

The taxonomy of the Alternaria spp. has been a subject, of controversy because of their high variability in conidial morphology and polymorphism displayed even in pure cultures. The published Korean literature on the genus Alternaria is scattered and fragmentary, and pertains to about 25 species with special emphasis on occurrence and pathogenicity, but mycological studies on this group of fungi are insufficient. This is the first series of detailed and consolidated account of Korean species of Alternaria, which includes 11 species; viz., Alternaria brassicae, A. brassicicola, A. cinerariae, A. dauci, A. dianthi, A. dianthicola, A. helianthi, A. helianthinffciens, A. iridicola, A. japonica and A. protenta. Detailed diagnostic descriptions, specific characterizations, taxonomic discussions and illustrations for each species are presented.

• Journal of Mushroom
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• v.21 no.4
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• pp.195-199
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• 2023

The fungus Alternaria alternata, responsible for causing brown to black spotting on numerous fruits and vegetables globally, was identified in 2022 as the causative pathogen of brown spot disease in potatoes in Korea. In pursuing potential inhibitors against A. alternata growth, we evaluated 15 mushroom culture filtrates: eight from Trametes spp. and seven from Polyporus spp., known for their antibacterial and anticancer properties. Antifungal activity was assessed by exposing each filtrate to A. alternata on a paper disc. Four filtrates displayed inhibitory action against the fungus, albeit with mild effects. Our findings highlight the potential of Trametes and Polyporus fungi as emerging antifungal candidates, offering promise in preventing potato brown spots.

• The Plant Pathology Journal
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• v.19 no.5
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• pp.221-226
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• 2003

Twenty universal rice primers (URPs) were used to detect PCR polymorphisms in 25 isolates of six different Alternaria species producing host specific toxins (HST). Eight URPs could be used to reveal PCR polymorphisms of Alternaria isolates at the intra- and inter-species levels. Specific URP-PCR polymorphic bands that are different from those of the other Alternaria spp. were observed on A. gaisen and A. longipes isolates. Unweighted pair-group method with arithmetic mean (UPGMA) cluster analysis using 94 URP polymorphic bands revealed three clustered groups (A. gaisen group, A. mati complex group, and A. logipes group).

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.263-268
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• 1983

In a survey of seed-borne mycofloras of Glycine max, 21 species have been isolated. Alternaria tenuis, Aspergillus spp., Cercospora kikuchii, Penicillium spp. and Fusarium spp. were the predominant fungi. C. kikuchii was isolated more often from purple stained seed than from unstained seed, and Fusarium spp., Phomopsis sp., Aspergillus spp. and Penicillium spp. were isolated less frequently in stained than unstained seeds. In inoculation experiments, C. kikuchii, Colletotrichum dematitum, Phomopsis sp. produced mild to severe symptoms on leaves when suspension of their conidia and mycelia were sprayed on to plants. In soil inoculation experiments, Fusarium oxysporum, F. moniliforme and F. semitectum showed pathogenicity causing seed rot and seedling blight.

• Journal of Environmental Science International
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• v.14 no.8
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• pp.793-800
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• 2005

We isolated and identified microorganisms from the aerial environment of domestic museums. The fungi, Penicillium spp., Alternaria spp., and Cladosporium spp. were isolated in many museums. It seems that these fungi are related to biological degradation of textile remains. A total of 14 kinds of bacterial strains were isolated: Acinetobacter spp., Pseudomonas spp., Neisseria spp., Alcaligenes spp., Shigella spp., Klebsiella spp., Corynebacterium spp., Aerococcus spp., Bacillus spp., Micrococcus spp., Citrobacter spp., Erwinia spp., Salmonella spp., and Providencia spp. Acinetobacter spp., Pseudomonas spp., Neisseria spp., and Alcaligenes spp. were the predominate bacteria found in samples with a variety of bacteria. This suggests that there is a relationship between bacteria and the damage of textile remains. In the museum, we isolated Alternaria spp, Geotrichum spp., Penicillium spp. Acinetobacter spp., Pseudomonas spp., Alcaligenes spp. from the entrance, exhibit hall and storage, but they were found in smaller number and species in the exhibit cases and paulownia cases. We concluded that paulownia cases were not influenced by the microorganisms because of quality of care provided by the museum staff. Corynebacterium spp., and Bacillus spp. were not detected at the entrance and exhibit hall but were detected in paulownia cases. It is presumed that those bacteria did not flow in from outside, but resulted from contaminants in paulownia cases. In the distribution of microorganisms associated with textile remains, more fungi were detected than bacteria. Acinetobacter spp., Pseudomonas spp., and Neisseria spp., were isolated from silk items. Penicillium spp. and Cladosporium spp. were isolated in the silk and hump items. Aspergillus spp. and Penicillium spp. were isolated from the cotton items. On the other hands, there were no fungi strains in the wool items. Most of the isolated strains from textile remains were aerial microorganisms from the museum environment. These results suggest that textile remains were apt to contaminated by contact with the air.

• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.191-196
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• 1982

In order to prevent the losses of the rice by fungal deterioration during storage, fungal contaminants were isolated and identified from the grain samples (Milyang Nr.23) stored for seven months from December, 1978 to June, 1979 in silo, flat store and Tongari. Out of thirty cultures isolated from Korean paddy and brown rice samples, twenty seven species were identified, and there are eleven species of Aspergillus (A. caespitosus, A. condidus, A. chevalieri, A fischeri, A. fumigatus, A. flavus, A. nidulans, A. oryzae, A. ruber, A. sydowii, A. versicolor), five species of Penicillium (P. atramentosum, p. chrysogenum, P. cyaneofulvum, P. nototum, P. steckii), two species of each Alternaria (Al. faesiculata, Al. grisea) and Curvalaria (C, interseminata, C. tetromea), and one species of each Trichothecium roseum, Nigrospora sphaerica, Rhizopus nigricans, Fusarium spp., Mucor spp., Helminthosporium spp., and Gliocladiopsis spp. The major types of fungi grown on the surface of paddy during storage were A. flavus and A. candidus, while A. ruber and A. sydowii appeared in brown rice samples. And also A. candidus, A. versicolor and A. glacus groups were considered as major deteriorating microorganisms in stored brown and paddy rice in Korea.

• Food Science and Preservation
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• v.24 no.6
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• pp.857-864
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• 2017

To establish good storage practices for hulled barley against mycotoxin contamination, we measured occurrence of fungi and mycotoxin in hulled barley grains under various storage conditions. Hulled barley grains collected from two places were stored in five different warehouses: 1) two without temperature control, 2) one with temperature controlled at $12^{\circ}C$, 3) a chamber set at $15^{\circ}C/65%$ relative humidity, and 4) one seed storage set at $10^{\circ}C$. The samples were stored for six month with temperature and relative humidity monitored regularly. Every stored samples were retrieved after 0, 1, 3, and 6 month to investigate fungal and mycotoxin contamination. From the stored grains, Fusarium, Epicoccum, Alternaria, and Drechslera spp. were frequently detected. In the warehouses without temperature control, Fusarium and Alternaria spp. constantly decreased, whereas Drechslera spp. increased along with storage period. In the other warehouses with temperature controlled, Fusarium spp. decreased slowly and more than 2.5 log CFU/g of Fusarium spp. were detected after 6 month storage. The level of nivalenol was maintained during 0-3 month but increased after 6 month storage. There was no difference in the nivalenol levels between the warehouses. Therefore reducing storage period less than 6 months could be more effective to control nivalenol contamination in hulled barley grains.