• Research in Plant Disease
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• v.16 no.2
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• pp.129-135
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• 2010

PCR primers were developed to detect Pseudomonas savastanoi pv. phaseolicola, a causal agent of halo blight that occurs in all species of common bean (Phaseolus vulgaris L.), from the bean seeds. A primer set, Psp-JHF and Psp-JH-R, specifically amplified 513 bp fragment from Pseudomonas savastanoi pv. phaseolicola only. A nested primer set, psp-JH-F-ne and psp-JH-R-ne, designed from the $1^{st}$ PCR amplicon, amplified 169 bp fragment. The primer sets did not amplify any non-specific DNA from the seed extracts of Fabaceae including 4 beans, 2 soybeans, and 2 peas. The detection sensitivity of the nested PCR method developed in this study was much higher than that of ELISA and selective medium. PCR assays developed in this study should be useful to detect Pseudomonas savastanoi pv. phasolicola from the bean seeds.

• Research in Plant Disease
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• v.16 no.3
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• pp.306-311
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• 2010

To detect Fusarium mycotoxins, grain samples were collected from 32 rice fields all over the country and from 19 maize fields in eastern and midland provinces in Korea in 2009. Maize contamination with Fusarium species (54.9%) was higher than in rice (8.2%). Using Fusarium species specific PCR primer sets (Fg16 and VERT), 58 and 354 of total 506 isolates from maize samples were putatively identified as F. graminearum (11.5%) and F. verticillioides (70.0%), respectively. From rice samples, 276 of 315 isolates (87.8%) were putatively identified as F. graminearum but F. verticillioides was not identified. LC or LC-MS analysis of the samples revealed that fumonisin was the most commonly detected mycotoxin in maize samples but its level was below the regulation limit. Only two maize samples were contaminated with deoxynivalenol and zearalenone at the levels above the regulation limit. In rice samples, contamination with zearalenone was common but the levels were below the regulation limit. This study showed that most of the Korean maize and rice samples collected in 2009 were contaminated with Fusarium mycotoxins but the levels were below the Korean regulations for deoxynivalenol, fumonisin and zearalenone.

• Research in Plant Disease
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• v.7 no.1
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• pp.1-7
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• 2001

An isolate of Cucumber mosaic cucumovirus(CMV) was isolated from Hydrangea macrophylla for. otaksa(Sieb. et Zucc. ) Wils. showing mosaic symptoms, and designated as Hm-CMV. Hm-CMV was characterized by the tests of host range, physical properties, serological properties, RNA and coat protein compositions, and reverse transcription and polymerase chain reaction (RT-PCR) analysis. Twelve species in 4 families were used in the host range test of Hm-CMV and could be differentiated from Y-CMV used as a control CMV by the ringspot and line pattern on inoculated leaves of several tobacco plants. Thevirus produced local lesions on inoculated leaves of Chenopodium amarticolor, C. quinoa and Vigna unguiculata. The physical properties of the virus were as follows; thermal inactivation point(TIP) was 60$\^{C}$, dilution end point (DEP) was 10$\^$-3/, and longevity in vitro (LIP) was 3∼4 days. Hm-CMV was serologically identical to Y-CMV. SDS-polyaciylamide gel electrophoresis(SDS-PAGE) showed one major protein band of about 28 kDa. In RNA or dsRNA analysis, Hm-CMV consisted of four RNA or dsRNA species, but satellite RNA was not detected. In RT-PCR using CMV-common primer and CMV subgroup I-specific primer, bothe amplified expected size of about 490 bp and 200 bp DNA fragments from Hm-CMV, respectively. Restriction enzyme analysis of the 490 bp RT-PCR products using EcoR I and Msp I showed that Hm-CMV belonged to CMV subgroup I. However, Hm-CMV could be differentiated from other CMV subgroup I isolates by RNA fingerprinting by arbitrarily primed polymerase chain reaction (RAP-PCR).

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.280-288
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• 2018

In this study, an approach for the analysis of the five cephalopod species (octopus, long-arm octopus, squid, wet-foot octopus, beka squid) consumed in the Republic of Korea is developed. The samples were collected from the Southeast Asian countries Thailand, Indonesia, Vietnam, and China. The SYBR-green-based real-time qPCR method, based on the mitochondrial DNA genome of the five cephalopods was developed and validated. The intergroup variations in the mitochondrial DNA are evident in the bioinformatic analysis of the mitochondrial genomic DNA sequences of the five groups. Some of the highly-conserved and slightly-variated regions are identified in the mitochondrial cytochrome-c-oxidase subunit I (COI) gene, 16s ribosomal RNA (16s rRNA) gene, and 12s ribosomal RNA (12s rRNA) gene of these groups. To specify each five cephalopod groups, specific primer sets were designed from the COI, 16s rRNA and 12s rRNA regions. The specific primer sets amplified the DNA using the SYBR-green-based real-time PCR system and 11 commercially secured animal tissues: Octopus vulgaris, Octopus minor, Todarodes pacificus, Dosidicus gigas, Sepia esculenta, Amphioctopus fangsiao, Amphioctopus aegina, Amphioctopus marginatus, Loliolus beka, Loligo edulis, and Loligo chinensis. The results confirmed by a conveient way to calculate relative amplification levels between different samples in that it directly uses the threshold cycles (Ct)-value range generated by the qPCR system from these samples. This genomic DNA-based molecular technique provides a quick, accurate, and reliable method for the taxonomic classification of the animal tissues using the real-time qPCR.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.422-428
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• 2016

Ginkgo (Ginkgo biloba L.) is one of the most appropriate roadside trees because of a good transplantation nature and ability to grow well in urban environment. Ginkgo is a dioecious species. Sex discrimination of ginkgo is possible through comparing morphological characters of reproductive organs. However, it needs more than about twenty years for reproductive organs to appear after sexual maturity. Until now, ginkgo trees for roadside plantation have been planted without discriminating the sex because ginkgo trees have been usually planted before sexual maturity. Ginkgo nuts from the female ginkgo trees planted along the roadside emit a foul odor, and make much pollution on the streets. Thus in this study a novel SCAR marker (SCAR-GBM) for the early sex discrimination was developed. Primers were developed on the basis of the sequence of male-specific RAPD variants reported previously. False-negative problem of SCAR marker, probably caused by dominant nature, was resolved by using multiplex PCR using primers of both the SCAR-GBM and a universal primer set of atp1 region in mitochondria DNA, which resulted in improved discrimination efficiency. The results showed that DNA bands of 1,039 bp were commonly amplified by the atp1 primer set in male and female trees, and SCAR-GBM markers of 675 bp were specifically amplified only in male trees. Reproducible and specific discrimination of the multiplex PCR was finally confirmed by applying multiple male and female individuals.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.191-197
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• 2013

Two medium-leaf ecotypes (CY6069, CY6097) belonging to one species (Zoysia japonica) of Korean lawngrasses were selected in sod production fields in Jang Seong, Korea. They were reported to have distinct morphological and growth rate characteristics different from the preferred medium-leaf type zoysiagrass in Korea. This study was conducted to define further the genotypic difference at the molecular level and to develop DNA marker based on the specific DNA fragment. Polymorphic DNA fragments were first explored by using randomly amplified polymorphic DNA (RAPD) primers, which were then converted into PCR-based sequence characterized amplified region (SCAR) markers. The CY6069-specific primer set amplified about 550 bp successfully, while the CY6097 marker produced the expected 690 bp band, by which those markers were nominated by CY6069_550 and CY6069_690 SCARs, respectively. Together with the reported morphological and other phenotypic features, the SCAR markers confirmed in this study will be useful to identify those medium-leaf zoysiagrass genotypes when they are cultivated with other vegetatively propagated warm-season turfgrasses in sod farms.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.365-370
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• 2013

The plume fruit moth, Grapholita dimorpha Komai, a fruit tree pest occurring in the northeast Asia, was firstly reported to infest apple in Korea in 2009, but its direct damage to other fruit trees has been poorly studied. In this study, we investigated shoots and fruits of both peach and plum trees and compared their damage rates by G. dimorpha to those by G. molesta, a congeneric species. In order to discriminate the two moth species, we developed a molecular diagnosis method using species-specific primer sets on different PCR conditions and distinguished the two species collected from the damaged shoots or fruits. The shoots and fruits of peach were infested mostly by G. molesta. However, in plums, the shoots were damaged by G. molesta and the fruits mostly by G. dimorpha. In addition, these two species showed a clear difference in host preference in fruit damage, where 92.5% of the Grapholita moths collected in peach fruits were identified as G. molesta, but 97.0% of the moths in plum fruits were G. dimorpha. The difference of the damage between the two fruit trees may give important information for monitoring of the two moth species in these orchards.

• The Plant Pathology Journal
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• v.33 no.1
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• pp.43-52
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• 2017

A survey was conducted to determine the status of Lucerne transient streak virus (LTSV) in three high-yielding alfalfa regions in central Saudi Arabia (Riyadh, Qassim, and Hail) during 2014. Three hundred and eight symptomatic alfalfa, and seven Sonchus oleraceus samples were collected. DAS-ELISA indicated that 59 of these samples were positive to LTSV. Two isolates of LTSV from each region were selected for molecular studies. RT-PCR confirmed the presence of LTSV in the selected samples using a specific primer pair. Percentage identity and homology tree comparisons revealed that all Saudi isolates were more closely related to each other but also closely related to the Canadian isolate-JQ782213 (97.1-97.6%) and the New Zealand isolate-U31286 (95.8-97.1%). Comparing Saudi isolates of LTSV with ten other sobemoviruses based on the coat protein gene sequences confirmed the distant relationship between them. Eleven out of fourteen plant species used in host range study were positive to LTSV. This is the first time to document that Trifolium alexandrinum, Nicotiana occidentalis, Chenopodium glaucum, and Lathyrus sativus are new host plant species for LTSV and that N. occidentalis being a good propagative host for it.

• Korean Journal of Plant Taxonomy
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• v.34 no.1
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• pp.63-74
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• 2004

The genus Suaeda is one of the most popular plants on salt marsh areas in Korean Peninsular. The entities that comprise taxa in Korea exhibit widely overlapping ranges in all morphological attributes. Ramdom amplified polimorphic DNA (RAPD) markers were used to clarify taxonomic delimitation among the Korean taxa of Suaeda and to analyse genetic variations among the populations of S. japoniro in western and southern coastal regions. Six decamer primers amplified a total of 65 scorable bands, of which 61 were polymorphic. In all primers investigated, S. glauro of sect. Schanginia is the most distinctive species, compared with others of sect. Heterosperma. S. japonica, S. maritima, and S. malacosperma, which have been hardly distinguished each other by external morphology, were readily recognized by its specific DNA bands. The characteristic RAPD markers were identified local populations of S. japonica, but this feature was not revealed within population.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.195-203
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• 2012

In reared populations of Allomyrina dichotoma, commercial insects, the skin of last instar larvae was changed softer with opaque white, and infested grubs eventually died. To clarify the cause of the symptom, we collected the larvae of A. dichotoma from five farms and examined their intestinal bacterial florae using pyrosequencing technique. From those results, a member of Paenibacillus was found only in the larvae showing the symptom of disease. Through PCR analysis using a Paenibacillus specific primer set, we obtained the partial 16S rRNA gene sequence and confirmed the microbe as Paenibacillus sp. For clear identification, a whole guts was extracted from each larva showing the sign of the disease and incubated at $70^{\circ}C$ for 15 min to isolate spore forming bacteria. After then, each content of guts was cultured on $MYPGP_{NAL}$ agar medium($12.5{\mu}g/ml$ of nalidixic acid) at $30^{\circ}C$. The 16S rRNA gene sequence analysis for the isolated bacteria showed that they were closely related to P. rigui(97.9% similarity), to P. chinjuensis(96.1% similarity), and to P. soli(95.3% similarity). Additional tests including API test and cellular fatty acid composition analysis were performed, but the strain couldn't be identified at species level, suggesting it may represent novel species of the genus Paenibacillus.