Mycoplasma hyorhinis (M. hyorhinis) is considered an etiological agent of arthritis in suckling pigs. Recently, some M. hyorhinis strains were shown to produce pneumonia that is indistinguishable from the mycoplasmosis caused by M. hyopneumoniae. In this study, we developed a sensitive and specific PCR assay to detect M. hyorhinis and applied the developed PCR assay for detection of Mycoplasma infection in clinical piglets infected with M. hyorhinis. We developed a new PCR assay using a M. hyorhinis-specific primer pair, Mrhin-F and Mrhin-R, designed from the Mycoplasma 16S-23S rRNA internal transcribed spacer (ITS) region. The primers and probe for the assay were designed from regions in the Mycoplasma 16S-23S rRNA ITS unique to M. hyorhinis. The developed PCR assay was very specific and sensitive for the detection of M. hyorhinis. The assay could detect the equivalent of 1 pg of target template DNA, which indicates that the assay was very sensitive. In addition, M. hyorhinis PCR assay detected only M. hyorhinis and not any other Mycoplasma or bacterial spp. of other genera. The new developed PCR assay effectively detected M. hyorhinis infection in pigs. We suggest that this PCR assay using a M. hyorhinis-specific primer pair, Mrhin-F and Mrhin-R, could be useful and effective for monitoring M. hyorhinis infection in pigs.

Root-lesion nematodes, Pratylenchus sp., are recognized as one of the most important plant parasitic nematodes. They infest various crop plants and cause severe root damages which lead to the yield loss of agricultural crops. There are 72 species recorded in the world, but 14 species in Korea. Soil samples were collected from chrysanthemum cultivars in various regions. Morphological and molecular diagnosis firstly recognized two species as Pratylenchus kumamotoensis and P. pseudocoffeae in Korea. Morphologically, P. kumamotoensis characterized by pharyngeal gland lobes overlapping with intestine dorsally. P. pseudocoffeae, which is similar with P. coffeae, but pharyngeal gland lobes are longer than P. coffeae. In molecular diagnosis, nucleotide sequences of D2-D3 region (700-800 bp) within 28S rDNA and ITS region including ITS1, 5.8S and ITS2 (700-1,000 bp) between 18S and 28S rDNA were determined from collected samples. NCBI database comparison of D2-D3 of P. kumamotoensis and P. pseudocoffeae were 99% similar with those of corresponding species, respectively. ITS of P. pseudocoffeae was 99% similar within species. ITS sequence of P. kumamotoensis was firstly determined in this study. Distribution of P. kumamotoensis was only reported in Japan but P. pseudocoffeae is present in Japan and USA. Here we firstly report the presence of these two species in Korea.

A rust on Asiatic dayflower plant (Commelina communis L.) was found in Geoje, Korea, in August 2010. Uredia are mostly produced on abaxial leaf surface or elongated on stem, early naked, surrounded by the ruptured epidermis, cinnamon-brown. Uredospores are globose, ellipsoid or ovate, echinulate, yellowish brown or brown, 20-30 × 20-25 ㎛. On the basis of mycological characteristics and molecular data, the fungus was identified as Uromyces commelinae Cooke. The phylogenetic position of U. commelinae is separate from the other rusts where the economically important rusts of the Poaceae are situated. Although host ranges of the rust caused by U. commelinae were previously recorded, full descriptions and illustrations, including symptoms and signs have not been described. This is the first description of rust disease on C. communis plant with molecular identification, symptoms, and signs.

Nuclear ribosomal DNA (rDNA) was analyzed to identify inter-specific genetic relationships among 8 Cymbidium species (Cymbidium insigne, C. ensifolium, C. marginatum, C. faberi, C. gyokuchin, C. kanran, C. forrestii, and C. goeringii). Nuclear rDNA including 2 internal transcribed spacer (ITS) regions and 5.8S, was amplified using polymerase chain reaction and sequenced. The sequences were compared via pair-wise multiple alignment to determine the genetic relationships among the studied species. The lengths of the ITS1, ITS2, and 5.8S regions were 235 bp, from 255 bp to 257 bp, and from 153 bp to 165 bp, respectively. Sequence similarities in the ITS region ranged from 78.7% between C. gyokuchin and C. kanran to 96.8% between C. ensifolium and C. kanran. A phylogenetic tree was constructed from nuclear rDNA nucleotide sequence data of the 8 cymbidiums and 1 outgroup species to estimate genetic relationships. The tree revealed that cymbidiums could be classified by their ecological traits, such as their temperature preference or inflorescence pattern. The phylogenetic data is applicable for identification, classification, and breeding of cymbidiums.

Recently, ambrosia beetles have become very important pest of 2~5 year old apple trees with M9 dwarf rootstocks in South Korea. The beetles have killed the branches and stems of the young trees, especially, frozen damage trees in winter or drought stressed tree in spring. By the increase in planting area and weaken property in winter of M9 dwarf rootstock, ambrosia beetles are becoming a key pest in Korean apple orchards using M9 rootstock. According to the survey of damaged apple trees by ambrosia beetles, Xylosandrus germanus Blandford, Xyleborus apicalis Blandford and Xyleborinus saxeseni (Ratzeburg). These insects are hosts of the ambrosia fungi. ITS region of rDNA has shown to be a useful source for phylogenetic studies and identifying speices in previous published articles. We analyzed the nucleotide sequences of ITS1, 5.8S and ITS2 region of ambrosia fungi isolated from three ambrosia beetles, in order to observe molecular variation among the fungi strains and to reveal phylogenetic relationships.

Background : Korean Indigenous Hylotelephium erythrostictum is widely distributed in South Korea and is used in Korean traditional medicine. In this study, the phylogenetic analysis of Korean native Hylotelephium erythrostictum and related plants on Internal Transcribed Spacer (ITS) sequences were investigated to distinguish its origin. Methods and Results : The phylogenetic analysis of 6 species of Hylotelephium were investigated by ITS. The dendrogram was constructed by UPGMA(Unweighted Pair Group Method with Arithmetic Mean) clustering algorithm based on genetic similarity of ITS. In the ITS sequence analysis, the size of total was varied from 676 to 779 bp. The size of ITS 1 was rated at 287bp, while ITS 2 was rated at 123bp. The G+C content of ITS region was ranged from 60 to 66%. In the ITS tree, six species of Hylotelephium were monophyletic, and H. viviparum was the first branching within the clade. Conclusion : H. spectabile formed a clade with H. erythrostictum, while H. verticillatum formed with H. viviparum.

Background : Ixeris dentata is the perennial herbaceous plant in the Ixeris genera within the Compositae family. The whole plant has been used traditionally as herbal medicine. It is widely distributed in South Korea and the genetic difference among the plants harvested from different regions may differ due to the disparity in cultivation climate. Therefore, this research was performed to discriminate the I. dentata that are collected from four locations in South Korea based on sequence analysis of nrDNA-ITS region. Methods and Results : Genomic DNA was extracted from I. dentata obtained from Goesan, Dangjin, Yangpyeong, and Chuncheon. I. stonolifera was included for a comparison of genetic distance with I. dentata. PCR amplification was performed by using an universal barcode nrDNA-ITS primer for DNA barcoding. After sequencing, the data was aligned using ClustalW multiple alignment tool in BioEdit version 7.2.5 software. SNP and phylogenetic analysis were conducted with the MEGA7 program. Phylogenetic analysis was presented with Neighbor-joining method using the K2P model. Statistical significance are evaluated using bootstrap (1,000 replicates). PCR products were amplified with about 800bp length for the ITS1-4 sequences of all samples. Nineteen SNPs were detected within a 578bp fragment of the aligned sequences. The mean GC content was 51.88% for ITS1-4 sequences of them. The interspecific genetic distance between I. dentata and I. stonolifera was 0.029%. The highest region-specific distance was confirmed to 0.010% between the plants from Dangjin with Goesan and Chuncheon group. Meanwhile, the mean intraspecific distance among the plants from Yangpyeong was 0.002%. Conclusion : In the phylogenetic analysis, the plants from Goesan and Chuncheon were placed within the same clade, while the plants from Dangjin formed independent clade. On the other hand, the plants from Yangpyeong were not grouped into one clade followed by the intraspecies variation. In conclusion, the data from the research will be useful for the regional identification of Dangjin, even if it is required to perform some additional researches.

The 12 cultivars of the Jeju native Citrus are considered to have originated from China. However, the origin of the cultivar ‘Byungkyool’ (Citrus platymamma Hort. ex Tanaka) is not clearly known. We performed PCR analysis by using three primer sets designed from the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) to analyze the phylogenetic relationship between the traditional citrus cultivars and the Byungkyool cultivar. Sequence length of the nrDNA ITS1 region of JNCPCRI (Jeju Native Citrus platymamma Citrus Research Institute) cultivar was 247 bp, 8the ITS2 region was 228 bp and the total ITS region (ITS1-5.8S-ITS2) was 638 bp. Analysis of the genetic relationship based on the sequence analysis at the ITS region of the JNCPCRI cultivar revealed that the ITS1 region of the cultivar was genetically the same as that of the Byungkyool (JQ990189) cultivar, and the ITS2 region was genetically similar to the Binkyool (JQ990180), Hongkyool (JQ990178), Dangyooja (JQ990179), and Pyunkyool (JQ990181) cultivars. Moreover, the total ITS region in the 5.8S rDNA region was genetically similar to the Hongkyool (JQ990178) cultivar. In addition, the total ITS region of the JNCPCRI cultivar was the most closely related to the Cheongkyool (JQ990183) cultivar and has been reported to originate from the Binkyool (JQ990180) and Pyunkyool (JQ990181) cultivars. Although the JNCPCRI cultivar was morphologically the same as the Byungkyool (JQ990189) cultivar, the ITS region showed genetic heterogeneity. Taken together, we conclude that the genetic variation in the ITS region of JNCPCRI cultivar suggests that it was propagated through fertilization with the surrounding citrus cultivars.

Background : Correct identification of Panax species is important to ensure food quality, safety, authenticity and health for consumers. This paper describes a high resolution melting (HRM) analysis based method using internal transcribed spacer (ITS) and 5.8S ribosomal DNA barcoding regions as target (Bar-HRM) to obtain barcoding information for the major Panax species and to identify the origin of ginseng plant. Methods and Results : A PCR-based approach, Bar-HRM was developed to discriminate among Panax species. In this study, the ITS1, ITS2, and 5.8S rDNA genes were targeted for testing, since these have been identified as suitable genes for use in the identification of Panax species. The HRM analysis generated cluster patterns that were specific and sensitive enough to detect small sequence differences among the tested Panax species. Conclusion : The results of this study show that the HRM curve analysis of the ITS regions and 5.8S rDNA sequences is a simple, quick, and reproducible method. It can simultaneously identify three Panax species and screen for variants. Thus, ITS1HRM and 5.8SHRM primer sets can be used to distinguish among Panax species.

The bramble cultivated widely in South Korea, which is known as Bokbunja-ddal-gi, is regarded as having originated from Korean native Rubus coreanus. This study was carried out to obtain basic phylogenetic information on Korean cultivated bramble (KCB) by comparing the internal transcribed spacer (ITS) regions with those of R. coreanus, blackberry (R. lanciniatus), black (R. occidentalis) and red (R. idaeus) raspberry. Sequences of the ITS 1 suggest that some KCB accessions share a significant similarity with both R. occidentalis and R. coreanus in the ITS 1 region. The ITS 2 sequences of the three KCB accessions clustered more closely to those of two R. occidentalis accessions than to those of R. coreanus. These results suggest that there exist variations in the sequences of ITS among KCB accessions and KCB accessions are more closely related to black raspberry than R. coreanus in the ITS regions.