• Mycobiology
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• v.51 no.6
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• pp.388-392
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• 2023

A yeast strain, designated as JAF-11^T, was isolated from flower of Prunus mume Sieb. et Zucc. in Gwangyang, Republic of Korea. Phylogenetic analysis showed that strain JAF-11^T was closely related to Neodothiora populina CPC 39399^T with 2.07 % sequence divergence (12 nucleotide substitutions and three gaps in 581 nucleotides) in the D1/D2 domain of the large subunit (LSU) rRNA gene, and Rhizosphaera macrospora CBS 208.79^T with 4.66 % sequence divergence (25 nucleotide substitutions and five gaps in 535 nucleotides) in the internal transcribed spacer (ITS) region. Further analysis based on the concatenated sequences of the D1/D2 domain of the LSU rRNA gene and the ITS region confirmed that strain JAF-11^T was well-separated from Neodothiora populina CPC 39399^T. In addition to the phylogenetic differences, strain JAF-11^T was distinguished from its closest species, Neodothiora populina CPC 39399^T and Rhizosphaera macrospora CBS 208.79^T belonging to the family Dothioraceae by its phenotypic characteristics, such as assimilation of carbon sources. Hence, the name Neodothiora pruni sp. nov. is proposed with type strain JAF-11^T (KACC 48808^T; MB 850034).

• ALGAE
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• v.39 no.2
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• pp.75-96
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• 2024

Rhodomonas (Cryptophyceae) and species assigned to this genus have undergone numerous taxonomic revisions. This also applies to R. marina studied here as it was originally assigned as a species of Cryptomonas and later considered a variation of R. baltica, the type species. Despite being described more than 130 years ago, R. marina still lacks a comprehensive characterization. Light and electron microscopy were employed to delineate a strain from western Greenland. The living cells were 18 ㎛ long and 9 ㎛ wide, elliptical in shape with a pointed to rounded posterior and truncated anterior in lateral view. Two sub-equal flagella emerged from a vestibulum, where also a furrow extended. In transmission electron microscopy, the furrow was associated with a tubular gullet and the pyrenoid embedded in a deeply lobed chloroplast. The chloroplast contained DNA in perforations and was surrounded by starch grains. A tubular nucleomorph was enclosed within the pyrenoid matrix. In scanning electron microscopy, the inner periplast consisted of rectangular plates with rounded edges and posteriorly these were replaced by a sheet-like structure. The water-soluble pigment was Crypto-Phycoerythrin type I (Cr-PE 545). A phylogenetic inference based on SSU rDNA confirmed the identity of strain S18 as a species of Rhodomonas as it clustered with congeners but also Rhinomonas, Storeatula, and Pyrenomonas. These genera formed a monophyletic clade separated from a diverse assemblage of other cryptophyte genera. To further explore the phylogeny of R. marina a concatenated phylogenetic analysis based on the SSU rDNA-ITS1-5.8S rDNA-ITS2-LSU rDNA region was performed but included only closely related species. The secondary structure of nuclear internal transcribed spacer 2 was predicted and compared to similar structures in related species. Using morphological and molecular signatures as diagnostic features the description of R. marina was emended.

• Parasites, Hosts and Diseases
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• v.62 no.1
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• pp.85-97
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• 2024

This study aimed to describe the morphological and molecular characteristics of Paralecithodendrium longiforme (Digenea: Lecithodendriidae) adults and cercariae isolated in Thailand. Adult flukes were isolated from the Chinese pipistrelle bat (Hypsugo sp.), and cercariae were detected in the viviparid snail (Filopaludina martensi martensi) from Chiang Mai province. The morphological characteristics were observed and described using conventional methods, and the molecular characteristics with internal transcribed spacer 2 (ITS2) and 28S rDNA gene sequences. The adult flukes were fusiform, 0.84-0.98 mm in length, and 0.37-0.49 mm in width, and were distinguishable from other species by the presence of longitudinal uterine coils. The cercariae were nonvirgulate xiphidiocercariae, with the oral sucker bigger than the acetabulum, the tail without fin fold, a body size of 117.5-138.3×48.3-52.2 ㎛, and a tail size of 100.7-103.7×15.0-18.9 ㎛. Molecular studies revealed that the adults and cercariae shared 99.3% (ITS2) and 99.6% (28S rDNA) homology with each other. They were phylogenetically close to P. longiforme with an identity of 94.5% for ITS2 and 98.7% for 28S rDNA. This study provides new information on the natural definitive host and first intermediate host of P. longiforme in Thailand. The discovery of its cercarial stage in Filopaludina snails highlights the importance of monitoring the associated second intermediate host and prevention and control of this potentially zoonotic trematode.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.377-385
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• 2017

Estimates of evolutionary sequence divergence and inference of a phylogenetic tree for eight delphacid planthopper species were based on the full-length nucleotide sequence of the internal transcribed spacer 2 (ITS2) region. Size of the ITS2 DNA sequence varied from 550 bp in Sogatella furcifera to 699 bp in Nilaparvata muiri. Nucleotide sequence distance ($d{\pm}S.E.$) was lowest between N. muiri and N. bakeri ($0.001{\pm}0.001$), and highest between Ecdelphax cervina and Stenocranus matsumurai ($0.579{\pm}0.021$). Sequence distance between N. lugens and other planthoppers ranged from $0.056{\pm}0.008$ (N. muiri) to $0.548{\pm}0.021$ (S. matsumurai). In the neighbor-joining phylogenetic tree, all planthoppers were clustered separately into a species group, except N. muiri and N. bakeri. The ITS2 nucleotide sequence of N. lugens was used to design four loop-mediated isothermal amplification (LAMP) primer sets (BPH-38, BPH-38-1, BPH-207, and BPH-92) for N. lugens species-specific detection. After the LAMP reaction of three rice planthoppers, N. lugens, S. furcifera, and Laodelphax striatellus, with the four LAMP primer sets for 60 min at $65^{\circ}C$, LAMP products were observed in the genomic DNA of N. lugens only. In the BPH-92 LAMP primer set, the fluorescence relative to that of the negative control differed according to the amount of DNA (0.1 ng, 10 ng, and 100 ng) and incubation duration (20 min, 30 min, 40 min, and 60 min). At $65^{\circ}C$ incubation, the difference was clearly observed after 40 min with 10 ng and100 ng, but with a 60-min incubation period, the minimum DNA needed was 0.1 ng. However, there was little difference in fluorescence among all DNA amounts tested with 20 or 30 min incubations.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.65-76
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• 2006

Scz1, an isolate of Sclerotinia homoeocarpa, was recently reported as a novel pathogen responsible for dollar spot disease in Zoysiagrass, a warm season turfgrass. Scz1 possessed different characteristics on mycelial pigment, mycelial affinity and host pathogenecity compared to those of Scb1, a typical isolate, obtained from creeping bentgrass, a cool season turfgrass. In this study, only three isolates, Scz1, Scz2(another analogous isolate of Sclerotinia homoeocarpa from zoysiagrass), and Scb1, were examined at the molecular level using the internal transcribed spacer(ITS) and random amplified polymorphic DNA(RAPD) assays to verify their identification and genetic variation. As a result of ITS assay, partial ITS sequences of three isolates showed 94-97% similarity with a standardized ITS sequence of S. homoeocarpa registered on BLAST. In the analysis of RAPD, range value through similarity matrix was 0.167 between Scz1 and Scb1, 0.139 between Scz2 and Scb1, and 0.713 between Scz1 and Scz2, respectively. Furthermore, tendegram analysis indicated that Scz1 and Scz2, unlike Scb1, were clustered together as accompanying a high genetic similarity. In in vitro fungicide bioassay, $EC_{50}$ value representing the sensitivity degree to propiconazole, a well-known fungicide for dollar spot disease, was 0.012 ${\mu}g/ml$ for Sczl, 0.003 ${\mu}g/ml$ for Scz2, and 0.030 ${\mu}g/ml$ for Scb1. From all data taken, we concluded that both Scz1 and Scz2 belonged to one group of S. homoeocarpa, since they exhibit the same host range and high level of genetic similarity, whereas their chemical competences to a fungicide were different. This study would provide further approach for assessing genetic diversity of S. homoeocarpa isolates as well as characterizing individual isolate against chemical exposure.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.234-241
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• 2019

An intensive interaction between yeasts and insects has highlighted their relevance for attraction to food and for the insect's development and behavior. Yeast associated in the gut of insects secretes cellulase which aided in the food digestion (cellulose degradation). Three strains of cellulose-degrading yeast were isolated from the gut of adult grasshoppers collected in Gyeonggi Province, South Korea. The strains $ON22^T$, $G10^T$, and $G15^T$, showed positive cellulolytic activity in the carboxymethyl cellulose (CMC)-plate assay. The phylogenetic tree based on sequence analysis of D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions revealed that the strains $ON22^T$ (100 and 98.4% sequence similarities in D1/D2 domains and ITS) and $G10^T$ (99.8 and 99.5% in D1/D2 domain and ITS region) were most closely related to the species Moesziomyces aphidis JCM $10318^T$; $G15^T$ (100% in D1/D2 domains and ITS) belongs to the species Moesziomyces antarcticus JCM $10317^T$, respectively. Morphology and biochemical test results are provided in the species description. Cellulase with its massive applicability has been used in various industrial processes such as biofuels like bioethanol productions. Therefore, this is the first report of the cellulolytic yeast strains $ON22^T$, $G10^T$, and $G15^T$ related to the genus Moesziomyces in the family Ustilaginaceae (Ustilaginales), in Korea.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.5-13
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• 2011

In this study, seven Trichoderma species (33 strains) were classified using secondary metabolite profile-based chemotaxonomy. Secondary metabolites were analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) and multivariate statistical methods. T. longibrachiatum and T. virens were independently clustered based on both internal transcribed spacer (ITS) sequence and secondary metabolite analyses. T. harzianum formed three subclusters in the ITS-based phylogenetic tree and two subclusters in the metabolitebased dendrogram. In contrast, T. koningii and T. atroviride strains were mixed in one cluster in the phylogenetic tree, whereas T. koningii was grouped in a different subcluster from T. atroviride and T. hamatum in the chemotaxonomic tree. Partial least-squares discriminant analysis (PLS-DA) was applied to determine which metabolites were responsible for the clustering patterns observed for the different Trichoderma strains. The metabolites were hetelidic acid, sorbicillinol, trichodermanone C, giocladic acid, bisorbicillinol, and three unidentified compounds in the comparison of T. virens and T. longibrachiatum; harzianic acid, demethylharzianic acid, homoharzianic acid, and three unidentified compounds in T. harzianum I and II; and koninginin B, E, and D, and six unidentified compounds in T. koningii and T. atroviride. The results of this study demonstrate that secondary metabolite profiling-based chemotaxonomy has distinct advantages relative to ITS-based classification, since it identified new Trichoderma clusters that were not found using the latter approach.

• The Plant Pathology Journal
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• v.22 no.1
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• pp.36-45
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• 2006

Twenty isolates of Didymella bryoniae were isolated from infected cucurbit plants in various growing areas of southern Korea in 2001 and 2002. Random Amplified Polymorphic DNA (RAPD) group [RG] I of D. bryoniae was more virulent than RG IV to watermelon. Virulence of the RG I isolate was strong to moderate to cucumber, whereas that of the RG IV varied from strong, moderate to weak. Two hundred seventy-three amplified fragments were produced with 40 primers, and were analyzed by a cluster analysis using UPGMA method with an arithmetic average program of NTSYSPC. At the distance level of 0.7, two major genomic DNA RAPD groups were differentiated among 20 isolates. The RG I included 7 isolates from watermelon and one isolate from melon, whereas the RG IV included 12 isolates from squash, cucumber, watermelon and melon. Amplification of internal transcribed spacer (ITS) region and small subunit rRNA region from the 20 isolates yielded respectively a single fragment. Restriction pattern with 12 restriction enzymes was identical for all isolates tested, suggesting that variation in the ITS and small subunit within the D. bryoniae were low. Amplification of the genomic DNAs of the tested isolates with the sequence characterized amplified regions (SCAR) primer RG IF-RG IR specific for RG I group resulted in a single band of 650bp fragment for 8 isolates out of the 20 isolates. Therefore, these 8 isolates could be assigned into RG I. The same experiments done with RG IIF-RG IIR resulted in no amplified PCR product for the 20 isolates tested. An about 1.4 kb-fragment amplified from the RG IV isolates was specifically hybridized with PCR fragments amplified from genomic DNAs of the RG IV isolates only, suggesting that this PCR product could be used for discriminating the RG IV isolates from the RG I isolates as well other fungal species.

• Research in Plant Disease
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• v.22 no.2
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• pp.127-131
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• 2016

During the year 2014, black locust (Robinia pseudoacacia L.) had been observed with dark brown spots on the leaves at Andong, Cheongsong, Mungyeong in Korea. Symptoms initially appeared as small, black lesions on the leaves, and sometimes, the leaves become yellow and ultimately leads to fall off the leaves. The pathogenic fungus grown in potato dextrose agar was white or sometime gray with mycelia in tufts and from which numerous conidia were produced. The conidia were straight and fusiform in shape and measured $8.3-17.2{\times}2.5-4.1{\mu}m$. Internal transcribed spacer (ITS) rRNA sequence analysis for sequence similarity of the ITS region revealed 100% identity with nucleotide sequences for Colletotrichum acutatum. The morphological characteristics, pathogenicity and molecular data have been confirmed that the symptomatic pathogen was C. acutatum. This is the first report of anthracnose caused by C. acutatum on black locust in Korea.

• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.677-681
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• 2013

Paragonimiasis is an important food-borne parasitic zoonosis caused by infection with lung flukes of the genus Paragonimus. Of the 7 members of the genus known in Thailand until recently, only P. heterotremus has been confirmed as causing human disease. An 8th species, P. pseudoheterotremus, has recently been proposed from Thailand, and has been found in humans. Molecular data place this species as a sister species to P. heterotremus, and it is likely that P. pseudoheterotremus is not specifically distinct from P. heterotremus. In this study, we collected metacercariae of both nominal species (identification based on metacercarial morphology) from freshwater crabs from Phetchabun Province in northern Thailand, Saraburi Province in central Thailand, and Surat Thani Province in southern Thailand. In addition, we purchased freshwater crabs imported from Myanmar at Myawaddy Province, western Thailand, close to the Myanmar-Thailand border. The DNAs extracted from excysted metacercariae were PCR-amplified and sequenced for ITS2 and cox1 genes. The ITS2 sequences were nearly identical among all samples (99-100%). Phylogenies inferred from all available partial cox1 sequences contained several clusters. Sequences from Indian P. heterotremus formed a sister group to sequences from P. pseudoheterotremus-type metacercariae. Sequences of P. heterotremus from Thailand, Vietnam, and China formed a separate distinct clade. One metacercaria from Phitsanulok Province was distinct from all others. There is clearly considerable genetic variation in the P. heterotremus complex in Thailand and the form referred to as P. pseudoheterotremus is widely distributed in Thailand and the Thai-Myanmar border region.