• The Plant Pathology Journal
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• v.18 no.4
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• pp.225-227
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• 2002

Moth orchid plants with yellowing blight and root rot symptoms were collected, and a total of 54 isolates of Fusarium spp. was obtained from roots and leaf bases of the diseased plants. The isolates were identified based on their morphological characteristics. Out of the 54 isolates of Fusarium spp., 42 isolates were identified as F. solani, 5 isolates as F. oxysporum, and 7 as F. proliferatum. Isolates of the three Fusarium spp. were tested for pathogenicity to moth orchid plants by artificial inoculation. All the Fusarium spp. induced root rot of the host plants. The symptoms progressed up to the basal part of the leaves, which later caused yellowing blight. The symptoms induced on the plants by artificial inoculation with the Fusarium spp. isolates were similar to those observed in greenhouses. The present study reveals that F. oxysporum, F. proliferatum, and F. solani cause root rot of moth orchid, and that F. solani is the main pathogen of the disease.

• Mycobiology
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• v.29 no.4
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• pp.224-226
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• 2001

Inflorescence of Allium thunbergii was found to be severely infected with Fusarium sp. The flower was covered with the fungus and eventually failed to form seeds. The causal fungus was identified as F. proliferatum(Matsushima) Nirenberg based on the cultural and morphological characteristics. Pathogenicity of the fungus was proved by artificial inoculation onto the healthy plants. This is the first record of this disease from Korea.

• Research in Plant Disease
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• v.21 no.4
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• pp.326-329
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• 2015

Fusaric acid is a mycotoxin produced by species of the fungus Fusarium and can act synergistically with other Fusarium toxins. In order to develop a specific detection method for fusaric acid-producing fungus, PCR primers were designed to amplify FUB10, a transcription factor gene in fusaric acid biosynthetic gene cluster. When PCR with Fub10-f and Fub10-r was performed, a single band (~550 bp) was amplified from F. oxysporum, F. proliferatum, F. verticillioides, F. anthophilum, F. bulbicola, F. circinatum, F. fujikuroi, F. redolens, F. sacchari, F. subglutinans, and F. thapsinum, all of which were known for fusaric acid production. Whereas the FUB10 specific band was not amplified from Fusarium species known to be trichothecene producer. Because production of fusaric acid can co-occur in species that also produce fumonisin mycotoxins, we developed a multiplex PCR assay using the FUB10 primers as well as primers for the fumonisin biosynthetic gene FUM1. The assay yielded amplicons from fumonisin producers such as F. proliferatum and F. verticillioides, allowing for the simultaneous detection of species with the genetic potential to produce both types of mycotoxins.

• Mycobiology
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• v.35 no.3
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• pp.162-165
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• 2007

Thirty seven species of Fusarium were evaluated for their ability of producing extracellular enzymes using chromogenic medium containing substrates such as starch, cellobiose, CM-cellulose, xylan, and pectin. Among the tested species Fusarium mesoamericanum, F. graminearum, F. asiaticum, and F. acuminatum showed high ${\beta}$-glucosidase acitivity. Xylanase activity was strongly detected in F. proliferatum and F. oxysporum. Strong pectinase activity was also found in F. oxysporum and F. proliferatum. Amylase activity was apparent in F. oxysporum. No clear activity in cellulase was found from all the Fusarium species tested.

• Mycobiology
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• v.51 no.3
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• pp.186-194
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• 2023

In July 2021, wilting symptoms were observed in adult and seedling hemp (Cannabis sativa L. cv. Cherry Blossom) plants grown in a greenhouse. As the disease progressed, yellowing and wilting symptoms on the leaves developed, resulting in whole plant death. In seedling plants, typical damping-off symptoms were observed. To identify the pathogen, the roots of diseased plants were sampled, surface sterilized, and cultured on potato dextrose agar (PDA) media. From the culture, 4 different fungal isolates were recovered and purely cultured. Each fungal isolate showed distinct growth shapes and color development on malt extract agar, oatmeal agar, sabouraud dextrose agar, and PDA media. Microscopic observation and molecular identification using ribosomal DNA internal transcribed spacer sequencing identified them as 3 Fusarium spp. and 1 Thielaviopsis paradoxa. Additional sequencing of elongation factor 1-alpha and b-tubulin regions of 3 Fusarium spp. revealed that 2 of them are Fusarium solani, and the other one is Fusarium proliferatum. To examine which isolate can act as a causal agent of wilt disease of hemp, each isolate was tested for their pathogenicity. In the pathogenicity test, F. solani AMCF1 and AMCF2, and F. proliferatum AMCF3, but not T. paradoxa AMCF4, were able to cause wilting disease in hemp seedlings. Therefore, we report that F. solani AMCF1 and AMCF2, and F. proliferatum AMCF3 as causal agents of Fusarium wilt of hemp plants. To our knowledge, this is the first report of the wilt disease of C. sativa L. caused by Fusarium spp. in Korea.

• Mycobiology
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• v.41 no.4
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• pp.225-233
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• 2013

Gibberella fujikuroi species complex (GFSC) was isolated from rice (Oryza sativa L.) seed samples from ten Asian countries and investigated for incidence of GFSC, molecular characteristics, and pathogenicity. Regardless of geographic origin, GFSC was detected with incidences ranging from 3% to 80%. Four species, Fusarium fujikuroi, F. concentricum, F. proliferatum, and F. verticillioides, were found to show an association with rice seeds, with F. fujikuroi being the predominant species. In phylogenetic analyses of DNA sequences, no relationship was found between species, isolates, and geographic sources of samples. Unidentified fragments of the ${\beta}$-tubulin gene were observed in ten isolates of F. fujikuroi and F. verticillioides. With the exception of three isolates of F. fujikuroi, F. fujikuroi, F. proliferatum, and F. verticillioides were found to have FUM1 (the fumonisin biosynthetic gene); however, FUM1 was not found in isolates of F. concentricum. Results of pathogenicity testing showed that all isolates caused reduced germination of rice seed. In addition, F. fujikuroi and F. concentricum caused typical symptoms of bakanae, leaf elongation and chlorosis, whereas F. proliferatum and F. verticillioides only caused stunting of seedlings. These findings provide insight into the characteristics of GFSC associated with rice seeds and might be helpful in development of strategies for management of bakanae.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.217-222
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• 2011

Job's tears (Coix lacryma-jobi) is native to East Asia, and grains of the plant are used as health food and medicinal material. Head blight symptoms of the plant were frequently observed during disease surveys in Korea from 2006 to 2008. The symptoms were characterized as discoloration of husks, and subsequently inside of mature grains were shriveled or emptied. One hundred fifty nine isolates of Fusarium species were obtained from the disease symptoms of the plant collected from several locations in the country. Out of the isolates, the most frequently isolated Fusarium species were F. graminearum (34%), F. proliferatum (14.5%), F. verticillioides (10.1%), F. equiseti (6.9%), and F. fujikuroi (6.3%). Other Fusarium species isolated were F. subglutinans, F. semitectum, F. poae, and F. sporodochioides. Elongation factor 1 alpha gene sequences of the isolates were used for phylogenetic analysis. Analyses of the sequences revealed that the isolates were confirmed to be identical with each reference species of NCBI GenBank. Pathogenicity tests showed that F. graminearum, F. proliferatum and F. verticillioides were strongly virulent to grains of Job's tears. The present study is the first report of head blight of Job's tears caused by Fusarium species in Korea.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.357-363
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• 2012

Several species belonging to the Gibberella fujikuroi species (Gf ) complex are commonly associated with rice and corn, not only causing serious diseases, but also producing fumonisins, a group of mycotoxins harmful to animals and humans. To characterize the population structure of the putative fumonisin-producing Gf complex in Korea, we obtained 276 candidate isolates from rice and corn harvested in 2009 and 2010 by diagnostic polymerase chain reaction with several specific primer sets. Phylogenetic trees were constructed using multilocus sequences (combined RPB2 and EF1A, totaling 1.6 kb) from these isolates. Among the 135 isolates from rice, F. fujikuroi (teleomorph: G. fujikuroi; 59.3%) and F. proliferatum (G. intermedia; 13.3%) were predominant, followed by F. concentricum (5.9%). Additionally, twenty-five (18.5%) rice isolates belonged in a distinct subclade of F. commune, a non-member of the Gf complex. In contrast, F. verticillioides was the most predominant species (38.3%) among the 141 corn isolates, and followed by F. fujikuroi (27.7%), F. proliferatum (14.9%), F. subglutinans (7.1%), and F. concentricum (2.8%). A single mating type (MAT1-1) was found predominantly among the Gf complex isolates examined. Possible distinct subclades were detected within the populations of F. fujikuroi and F. proliferatum; however, this needs further confirmation. This is the first reported population-level characterization of putative fumonisin-producing Gf complex associated with rice and corn in Korea.

• The Korean Journal of Mycology
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• v.41 no.3
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• pp.142-148
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• 2013

Sorghum (Sorghum bicolor Moench) was traditionally grown on a small scale, however, at present its cultivation is getting momentum in terms of food and animal feed crop throughtout the Korea. Grain mold symptoms of the plant were frequently observed during disease surveys in Korea from 2007 to 2009. The symptoms were highly variable. Severely infected grain was fully covered with mold and partially infected grain may look normal or discolored. Ninety isolates of Fusarium species were obtained from the diseased plants collected from several locations in the country. Among the collected Fusarium isolates, 41 were identified as Fusarium thapsinum, 23 as F. proliferatum, 12 as F. graminearum, 5 as F. incarnatum, and 3 as F. equiseti based on their morphological and cultural characteristics. Elongation factor 1 alpha gene sequences of the isolates were used for phylogenetic analysis. Analyses of the sequences revealed that the isolates were confirmed to be identical with related species of NCBI GenBank. Pathogenicity tests showed that three dominant species, F. thapsinum, F. proliferatum and F. graminearum were strongly virulent to grains of sorghum. This study is the first report of sorghum grain mold caused by Fusarium species in Korea.

• Mycobiology
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• v.28 no.3
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• pp.158-162
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• 2000

Twenty-three isolates of Fusarium spp. were obtained from decayed citrus fruits in the fields and storages in 1998-1999. Of them, six and five isolates belonged to F. proliferatum and F. moniliforme, respectively, which were the most common. F. solani and F. sambucinum had each two isolates, F. equiseti had one isolate and seven isolates were unidentified. They produced symptoms of two types in pathogenicity test: those with leathery, beige to light or dark brown, and sunken lesions without surface mycelium (type-1) and those with lesions covered with white, beige or pink surface mycelium (type-2). Four of six isolates identified to F. proliferatum and two unidentified isolates produced type-1 lesions, and all isolates identified to F. moniliforme, F. solani, F. sambucinum, F. equiseti and five unidentified isolates produced type-2 lesions.