• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.100-108
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• 2016

An auxin-producing bacteria (strain 5-1) was isolated from button mushroom compost in Boryeong-Si, Chungcheongnam-Do. The 5-1 strain was classified as a novel strain of Enterobacter aerogenes based on chemotaxonomic and phylogenetic analyses. The isolated E. aerogenes 5-1 was confirmed to produce indole-3-acetic acid (IAA), one of the auxin hormones, using TLC and HPLC analyses. When the concentration of IAA was assessed by performing HPLC quantitative analysis, a maximum concentration of IAA of $109.9mgL^{-1}$ was detected in the culture broth incubated in R2A medium containing 0.1% L-tryptophan for 24 h at $35^{\circ}C$. Acidification of the culture was deemed caused by an increase of IAA because a negative relationship between IAA production and pH was observed. Supplementation with a known precursor of IAA production, L-tryptophan, appeared to induce maximal production at 0.1% concentration, but it reduced production at concentrations above 0.2%. To investigate the growth-promoting effects to crops, the culture broth of E. aerogenes 5-1 was used to inoculate water cultures and seed pots of mung bean and lettuce. In consequence, adventitious root induction and root growth of mung bean and lettuce were two times higher than those of the control.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.647-654
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• 2015

A prostrate species of Codium (Bryopsidales, Chlorophyta) was collected from Daejin on the eastern coast of Korea. This alga is morphologically characterized by a prostrate, adherent or pulvinate, dark green thallus that is tightly attached to substratum. The utricles are strongly grouped and cylindrical to slightly clavate. Their apex is rounded to capitated, and it frequently has an alveolate ornament. Hair scars are found in the upper portion of the utricle. The gametangia grow on a short pedicel in the upper part of the utricle. In the phylogenetic tree based on molecular data, this alga is placed in the same clade as C. mozambiquense in UPGMA analysis, and nests in a sister clade of C. lucasii subsp. capense and C. mozambiquense in ML and NJ analyses. However, the genetic distance between the sequences of the Korean alga and the two species is 1.3-1.9%, while that between the Korean alga and C. lucasii from Japan is 1.1% within intraspecific range. The divergence value between the Korean alga and C. lucasii from the type locality (Australia) is 2.7% considered to be interspecific range. As based on this genetic divergence value, the Korean alga together with Japanese C. lucasii can be separated from genuine C. lucasii from the type locality. However, the Korean alga is identified as C. lucasii until those entities are morphologically characterized in species level. This is the first record of C. lucasii in Korea

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.395-410
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• 2014

The genus Callophyllis is recorded as six separate species with imprecise species delimitation in Korea. To elucidate the species boundaries of Korean Callophyllis, we performed morphological observations and molecular analyses, and included three Japanese Callophyllis species from the type locality. From the results of molecular analyses using plastid rbcL and mitochondrial COI-5P genes, we confirmed ten Callophyllis species, including five cryptic ones: C. adhaerens, C. adnata, C. crispata, and C. japonica from Korea and Japan; C. hayamensis as an unrecorded species from Korea; C. cartilaginea, C. mollitia, C. repens, C. serratifolia, and C. undulata as new species from Korea. There were no Korean specimens that matched C. adnata or C. crispata from Japan, except Korean C. japonica, which formed a genetic group with the Japanese species. We obtained the interspecific divergences among the five cryptic species as 0.6-4.5% in rbcL and 2.8-8.4% in COI-5P. We recognized that the species diversity of Callophyllis has been underestimated from the northwestern Pacific region. The species boundary of Callophyllis from Korea and Japan will be a cornerstone to revealing the phylogenetic affinity of the genus distributed in both hemispheres of the western Pacific.

• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.163-167
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• 2015

Canine parvovirus (CPV) is a major diarrhea-causing agent in puppies. Since CPV type 2 (CPV-2) emerged in 1978, new antigenic variants including CPV-2a, CPV-2b, and CPV-2c have been identified in many countries. Two puppies died suddenly at a veterinary clinic in Gyeonggi province, South Korea. Two viruses were isolated in A72 cells, confirmed as CPV strains based on a CPV rapid kit and an indirect fluorescence test and designated QIACP1403 and QIACP1404. The nucleotide sequences of complete VP2 genes of QIACP1403 and QIACP1404 were determined, and the corresponding amino acid sequences were deduced. Molecular analyses revealed that the QIACP1403 and QIACP1404 isolates were type CPV-2b. Several mutated amino acids were detected on VP2 gene residues of the two isolates. Phylogenetic analyses showed that the two isolates were most closely related to strain CPV-BM11, which was isolated from Chinese dogs in 2011. Our results suggest that these isolates may be a candidate for a vaccine to prevent CPV infection in dogs after conducting passages of the isolates in an in vitro culture system.

• Korean Journal of Veterinary Research
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• v.52 no.1
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• pp.9-18
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• 2012

Rabies is a major zoonotic disease that causes approximately 55,000 human deaths worldwide on an annual basis. The nucleocapsid protein and glycoprotein genes of the Korean rabies virus (RABV) have been subjected to molecular and phylogenetic analyses. Although the phosphoprotein (P) has several important functions in viral infection and pathogenicity, the genetic characterizations of the P of Korean RABV isolates have not yet been established. In the present study, we conducted genetic analyses of P genes of 24 RABV isolates circulating in the Republic of Korea (hereafter, Korea) from 2008 to 2011. This study revealed that the P genes of Korean RABVs are genetically similar to those of RABV strains of lyssavirus genotype I including V739 (dogs, Korea), NNV-RAB-H (humans, India), NeiMeng925 (raccoon dogs, China), and RU9.RD (raccoon dogs, Russia). Among Korean isolates, the RABV P genes showed low variability in the variable domains among Korean isolates; they had specific consensus sequences and amino acid substitutions capable of identifying geographic characteristics and retained specific sequences thought to be important for viral function. These results provide important genetic characteristics and epidemiological information pertaining to the P gene of the Korean RABV.

• Journal of Mushroom
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• v.13 no.4
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• pp.275-281
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• 2015

An auxin-producing bacteria (A-1) was isolated from soils of Oyster mushroom farmhouse in Daejeon city, South Korea. The strain A-1 was classified as a novel strain of Ochrobactrum anthropi based on a chemotaxanomic and phylogenetic analyses. The isolate was confirmed to produce indole-3-acetic acid (IAA), one of auxin hormones, by TLC and HPLC analyses. The maximum concentration of IAA, $5.6mg\;L^{-1}$ was detected from the culture broth of O. anthropi A-1 incubated for 24 h at $35^{\circ}C$ in R2A broth containing 0.1% L-tryptophan. To investigate the growth-promoting effects to the crops, the culture broth of O. anthropi A-1 was inoculated to water cultures and seed pots of mung bean as well as lettuce. In consequence, the adventitious root induction and root growth of mung bean and lettuce were 2.7 and 1.4 times higher than those of the non-inoculated, respectively.

• ALGAE
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• v.21 no.4
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• pp.417-423
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• 2006

Morphology and molecular phylogeny of a red algal species, Hypnea flexicaulis that is recently described from Japan, were investigated based on 23 collections from Korea (21), Taiwan (1), and the Philippines (1). Hypnea flexicaulis has percurrent axes with flexuous, antler-like branches which have wide branching angles, and abaxially curved ultimate branchlets. In order to study DNA divergence and phylogenetic relationships of the species, we determined plastid rbcL and mitochondrial cox1 sequences from the 23 collections. All 21 specimens from five different locations in Korea were almost identical to H. flexicaulis from Japan in rbcL sequences. Although there was a difference of three to five base pairs (bp) between samples from Korea and the Philippines or between the Philippines and Taiwan, Bayesian analyses of the rbcL data showed that all specimens from Korea, Japan, the Philippines, and Taiwan were strongly monophyletic. However, it is interesting that specimens from the Philippines differed by 31-34 base pairs in mitochondrial cox1 gene from those of materials from Korea and Taiwan, which differed by one to seven bp in rbcL between them. Although H. boergesenii is different from H. flexicaulis in having many antler-like branchlets, both appeared as sisters in all analyses of the rbcL data. This is the first report of H. flexicaulis from Korea based on morphology, rbcL, and cox1 gene sequences.

• The Korean Journal of Mycology
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• v.47 no.2
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• pp.113-120
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• 2019

We isolated endophytic fungal strains from the roots of three medicinal crops, Ligusticum chuanxiong, Angelica gigas, and Cnidium officinale, cultivated at Yeongju, Korea. The fungal strains were identified based on their morphological characteristics and molecular analyses of their internal transcribed spacer, large subunit rDNA, and beta-tubulin regions. Thereby, we identified three previously unrecorded endophytic fungal species, Dactylonectria pauciseptata, Rhizopycnis vagum, and Sistotrema sernanderi, in Korea. In this report, we describe the morphological characteristics and phylogenetic analyses of these three fungal species.

• Journal of Marine Bioscience and Biotechnology
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• v.14 no.1
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• pp.51-60
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• 2022

A green alga specimen was collected from the eastern coast of Korea. This species shared the typical features of genus Ulva and was characterized by irregularly shaped thalli, relatively small and thick thallus, entire undulate margins without serrations, and one or two pyrenoids per cell. In a phylogenetic tree, based on sequences of the nuclear-encoded internal transcribed spacer region, it nests as a sister clade to a few species including Ulva ohnoi, which has a relatively large thallus. This Korean algal specimen differs from the species forming the same subclades, including U. ohnoi, Ulva fasciata, Ulva reticulata, and Ulva gigantean, and has a relatively small (3-8 cm) and thick (60-100 ㎛) thallus. Of these species, U. ohnoi, originally described from Japan, is similar to the Korean alga as it had a thick thallus of 30-90 ㎛, but it has microscopic serrations on the thallus margin, unlike the Korean alga. The genetic distance between the Korean alga species and the aforementioned species was determined to be 1.8%-4.8%, indicating an inter-specific divergence level at the genus Ulva. Herein, Ulva grossa sp. nov. (Ulvales, Chlorophyta) from Korea is described based on the morphological and molecular analyses.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.218-218
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• 2022

Granules-bound starch synthase II (GBSSII), one of the isoforms of granule-bound starch synthase (GBSS), is responsible for amylose synthesis by expressing in non-storage tissues such as leaf, stem, root, and pericarp. Up to date, little is known about this gene functions and basic knowledge of heritable characteristics of this gene, GBSSII. We identified functional haplotypes and performed evolutionary analyses on the GBSSII using 374 rice accessions (320 Korean bred and 54 wild) based on the classified groups. A total of 14 haplotypes were found, and almost all haplotypes (13) were functional, carrying 19 non-synonymous SNPs in two exons (exons 1 and 2). The lowest nucleotide diversity was detected in Tropical japonica (0.00145), while the highest pi-value was in Aus (0.01081), illustrating the signal of this gene evolution. The highest Tajima's D value in Aus (1.6380) indicates GBSSII gene domestication signature under balancing selection, while the lowest Tajima's D value in Temperate japonica (-0.8243) highlights that they were under positive selection, which may be purified due to the excess of rare alleles. The highest genetic differentiation was observed between Tropical japonica and aroma (F_ST = 0.921928). In contrast, the highest interbreed level was detected in Aus-admixture (F_ST = -0.20157). The genetic relatedness between and or among the wild and cultivated subpopulations was revealed through PCA, population structure, and phylogenetic analyses.