• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.31-37
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• 2017

This study aimed to investigate the morphology and reconstruct the phylogenetic relationships of Centrocestus formosanus originating from 5 species of freshwater fish, i.e., Esomus metallicus, Puntius brevis, Anabas testudineus, Parambassis siamensis, and Carassius auratus, in Chiang Mai province, Thailand. Sequence-related amplified polymorphism (SRAP) and phylogeny based on internal transcribed spacer 2 (ITS2) and mitochondrial cytochrome c oxidase subunit 1 (CO1) were performed. The results showed similar morphologies of adult C. formosanus from day 5 after infection in chicks. C. formosanus originated from 4 species of freshwater fish had the same number of circumoral spines on the oral sucker, except for those from C. auratus which revealed 34 circumoral spines. The phylogenetic tree obtained from SRAP profile and the combination of ITS2 and CO1 sequence showed similar results that were correlated with the number of circumoral spines in adult worms. Genetic variability of C. formosanus also occurred in different species of freshwater fish hosts. However, more details of adult worm morphologies and more sensitive genetic markers are needed to confirm the species validity of C. formosanus with 34 circumoral spines originating from C. auratus in the future.

• Parasites, Hosts and Diseases
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• v.51 no.5
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• pp.563-567
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• 2013

An ocular Toxocara canis infection is reported for the first time in Vietnam. A 34-year-old man residing in a village of Son La Province, North Vietnam, visited the National Eye Hospital (NEH) in August 2011. He felt a bulge-sticking pain in his left eye and loss of vision occurred over 3 months before visiting the hospital. The eye examination in the hospital showed damage of the left eye, red eye, retinal fibrosis, retinal detachment, inflammation of the eye tissues, retinal granulomas, and a parasitic cyst inside. A larva of Toxocara was collected with the cyst by a medical doctor by surgery. Comparison of 264 nucleotides of internal transcribed spacer 2 (ITS2) of ribosomal DNA was done between our Vietnamese Toxocara canis and other Toxocara geographical isolates, including Chinese T. canis, Japanese T. canis, Sri Lankan T. canis, and Iranian T. canis. The nucleotide homology was 97-99%, when our T. canis was compared with geographical isolates. Identification of a T. canis infection in the eye by a molecular method was performed for the first time in Vietnam.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.187-190
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• 2012

Various koji were prepared by fungi isolated from traditional nuruk and their quality characteristics were investigated. Acidity and saccharification power of their koji were ranged in 5.0~6.8 and 128sp~241sp. Nine fungi which were showed good quality and sensory evaluation were identified by analysis of their nucleotide sequences with PCR-amplified 18S rDNA internal transcribed spacer-1(ITS-1) and ITS-4 genes. Among them, six strains were identified as Aspergillus oryzae and the other strains were identified as Mycocladus corymbiferus, Rhizo-pus oryzae, Lichtheimia corymbifera.

• Mycobiology
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• v.47 no.1
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• pp.76-86
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• 2019

Scab disease caused by Venturia nashicola is of agroeconomic importance in cultivation of Asian pear. However, little is known about the degree of genetic diversity in the populations of this pathogen. In this study, we collected 55 isolates from pear scab lesions in 13 major cultivation areas in Korea and examined the diversity using sequences of internal transcribed spacer (ITS) region, ${\beta}$-tubulin (TUB2), and translation elongation factor-$1{\alpha}$ ($TEF-1{\alpha}$) genes as molecular markers. Despite a low level of overall sequence variation, we found three distinctive subgroups from phylogenetic analysis of combined ITS, TUB2, and $TEF-1{\alpha}$ sequences. Among the three subgroups, subgroup 1 (60% of isolates collected) was predominant compared to subgroup 2 (23.6%) or subgroup 3 (16.4%) and was distributed throughout Korea. To understand the genetic diversity among the subgroups, RAPD analysis was performed. The isolates yielded highly diverse amplicon patterns and none of the defined subgroups within the dendrogram were supported by bootstrap values greater than 30%. Moreover, there is no significant correlation between the geographical distribution and the subgroups defined by molecular phylogeny. Our data suggest a low level of genetic diversification among the populations of V. nashicola in Korea.

• The Korean Journal of Mycology
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• v.47 no.1
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• pp.29-34
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• 2019

A fungal isolate designated 17E029 was isolated from a soil sample in Jeju, Korea. The strain was similar to other Allantophomopsiella species in its morphological characteristics such as grey mycelia, conidiophore, and conidia sizes. The isolate produced aerial mycelia, which appeared grey on the reverse side of the media surfaces and turned black on the front side of the colonies. The conidiophores emanating from the hyphae were hyaline, grey, aseptate, branched, and $6.7{\sim}9.2{\times}1.8{\sim}2.5{\mu}m$. Conidiogenous cells were ovoid to subcylindrical, discrete, guttulate, and hyaline. Conidia were hyaline, aseptate, smooth, guttulate, oval to subcylindrical, irregular in shape, and $6.0{\sim}7.8{\times}3.0{\sim}3.4{\mu}m$. The strain was confirmed based on phylogenetic analysis of the closest related organism, A. pseudotsugae CBS 288.37, using the partial 28S, internal transcribed spacer rDNA regions, and partial RNA polymerase II second largest subunit locus (RPB2) gene sequences along with its culture characteristics. Therefore, morphological observations and phylogenetic analysis revealed that strain 17E029 is similar to the previously identified A. pseudotsugae. Hence, this species was described as A. pseudotsugae strain 17E029, which is a new record in Korea.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.499-503
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• 2020

Clubroot symptoms were frequently observed on the roots of Baecheongchae plants grown in vinyl greenhouses of a farmer located in Yangpyeong area of Korea during a disease survey in June 2019. The incidence of diseased Baecheongchae plants ranged from 30 to 90% in the vinyl greenhouses investigated. Many resting spores were found in the tissue of root galls collected. The resting spores were hyaline and spherical and measured 2.5-4.2 ㎛ in diameter. Three inoculum suspensions of resting spores prepared from the root galls were inoculated to the roots of healthy Baecheongchae plants. All the inoculum suspensions caused clubroot symptoms to appear on the roots of the inoculated Baecheongchae plants. The symptoms on the roots induced by artificial inoculation were similar to those observed in the plants of the vinyl greenhouses during the disease survey. Resting spores of the pathogen were recovered from the root galls of the inoculated plants. Three root gall isolates obtained from the inoculated plants were used for molecular identification. Comparing the isolates to the Plasmodiophora brassicae strains in GenBank, the amplification products demonstrated 100% similarity with the internal transcribed spacer (ITS2) sequences. The clubroot pathogen was identified as P. brassicae according to its morphological, pathological, and molecular characteristics. This is the first report of P. brassicae causing clubroot in Baecheongchae.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.40-45
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• 2010

The application of PCR analysis on the herbal medicine Moutan Cortex (Paeonia suffruticosa Andrews) was evaluated by the comparison of the genetic relationship based on the DNA sequence with Paeoniae Radix (Paeonia lactiflora Pallas) following development of specific primers. Moutan Cortex and Paeoniae Radix were distinguished through the PCR analysis based on the internal transcribed spacer (ITS-PCR) from nuclear ribosomal DNA region. The 294 bp PCR products both of Moutan Cortex and Paeoniae Radix was amplified by MIF1 and MIR1. And a Moutan Cortex specific 225 bp PCR amplification product was amplified by MIF2 and MIR1 primers. The 225 bp sequence could be successfully amplified from Mortan Cortex of dried herbal preparations. PCR analysis based on ITS (ITS-PCR) may be an efficient tool for the discrimination of Moutan Cortex.

• Korean Journal of Oriental Medicine
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• v.14 no.1
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• pp.129-135
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• 2008

Phylogenetic relationship and DNA polymorphism among local populations of the Asparagus cochinchinensis have been investigated based on nuclear ribosomal DNA ITS sequences and RAPD analysis in Korea. In result, two genetically distinct groups of local populations except Geoje were recognized by the phylogenetic tree both in rDNA-ITS and RAPD. One was called 'western coast group' that includes the Buan 1, 2 and Taean and the other was 'southern coast group' that includes Haenam, Yeosu and Namhae. Thus, the geographical relationship of Asparagus cochinchinensis was two well-typified clades. These results suggest that the geographical genetic variation of Asparagus cochinchinensis is closely connected with the slow and long period of propagation via the coast in Korean Peninsula.

• The Plant Pathology Journal
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• v.38 no.2
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• pp.131-145
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• 2022

Ceratocystis wilt disease has caused significant mortality in duku (Lansium domesticum) since 2014 and has now spread to all districts in South Sumatra, Indonesia. Recently, 16 isolates from duku representing populations from various districts in South Sumatra were isolated. Analysis for the morphological characteristic of the isolate showed that the population has a uniform morphology. Genetic analysis based on internal transcribed spacer (ITS) and β-tubulin sequences verified that the population has being dominated by the ITS5 haplotype of Ceratocystis fimbriata and a new ITS group, the ITS7b haplotype that was localized in Musi Banyuasin. Both haplotypes were highly pathogenic to duku. Inoculation tests on various forest and agroforestry plant hosts showed that both haplotypes were highly pathogenic to Acacia mangium, moderately pathogenic to Acacia carsicarpa, Eucalyptus urophylla, and Melaleuca cajuputi, but weakly pathogenic to Dyera costulata, Hevea brasiliensis, and Alstonia scholaris. Therefore, this pathogen becomes a serious threat to Indonesia's biodiversity due to its ability to infect forest and agroforestry plants, especially the indigenous ones.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.1
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• pp.155-166
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• 2011

The leaf beetle, $Chrysolina$ $aurichalcea$ (Coleoptera: Chysomelidae), is a pest damaging plants of Compositae. In order to understand the genetic diversity and geographic variation we sequenced a portion of mitochondrial COI gene (658 bp) and complete nuclear internal transcribed spacer 2 (ITS2) of the species collected from seven Korean localities. A total of 17 haplotypes (CACOI01~CACOI17), with the maximum sequence divergence of 3.04% (20 bp) were obtained from COI gene sequence, whereas 16 sequence types (ITS2CA01~ITS2CA16), with the maximum sequence divergence of 2.013% (9 bp) were obtained from ITS2, indicating substantially larger sequence divergence in COI gene sequence. Phylogenetically, the COI gene provided two haplotype groups with a high nodal support (${\geq}87%$), whereas ITS2 provided only one sequence type group with a high nodal support (${\geq}92%$). The result of COI gene sequence may suggest the presence of historical biogeographic barriers that bolstered genetic subdivision in the species. Different grouping pattern between COI gene and ITS2 sequences were interpreted in terms of recent dispersal, reflected in the ITS2 sequence. Finding of unique haplotypes and sequence types only from Beakryeng-Islet population was interpreted as an intact remnant of ancient polymorphism. As more samples are analyzed using further hyper-variable marker, further fruitful inference on the geographic contour of the species might be available.