• ALGAE
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• 제23권1호
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• pp.15-29
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• 2008

Many species in Gymnodiniales, which are unarmored dinoflagellates, are responsible for marine algal blooms and some of them have potent toxin in the cell. Their taxonomy has so far been well-defined, and several genera (e.g. Akashiwo, Gymnodinium, Karenia) have recently been re-described. In Korea, few works have been carried out on their taxonomical and molecular studies. This study focused on comparison of both morphological and molecular characteristics of five unarmored dinoflagellates on Korean coastal water: Akashiwo sanguinea, Cochlodinium polykrikoides, Gymnodinium catenatum, Gymnodinium impudicum and Karenia aureolum (=K. mikimotoi). Morphological characteristics observed here was in good accordance with the original descriptions of individual species. In addition, none of difference was found in morphological comparisons between the Korean and foreign strains. Furthermore, molecular analysis showed that the SSU rDNA sequences were generally identical according to each species. In some distinct features, A. sanguinea, which has generally the same morphological features, were divided into two groups: one was Korean isolates including European isolates, the other was American isolates. In the two groups, the nucleus was positioned differently: middle of the cells in the Korean isolates (GnSg02, GnSg03), near the epicone in American isolates (CCMP1593, CCMP1837). In addition, this was strongly supported by phylogenetic analysis, inferred from the SSU rDNA sequences. K. aureolum (GrAr01) was corresponded to European G. aureolum (=K. mikimotoi) in shape and position of nucleus, chloroplast, however, which is similar to K. digitata in view of having a finger-like sulcus. This was in good agreement with phylogenetic study of these species. G. catenatum have identical morphology except the ridge location, and their genotype of SSU rDNA was also identical to GenBank data of the same species. From this study, we found that the five Korean unarmored dinoflagellates are identical morphological characteristics and genotype to each species of foreign isolates.

• 한국수산과학회지
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• 제49권2호
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• pp.208-213
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• 2016

The re-identification of two Korean tonguefishes, Cynoglossus interruptus and Symphurus orientalis, was carried out using eight specimens collected from Korean waters in 2007 and 2013. C. interruptus is characterized by having a single row of scales between rows connected to the supraorbital line and the middle lateral line, 107–113 dorsal fin rays, 86–89 anal fin rays, and 53–55 vertebrae. S. orientalis is characterized by having a 1-2-2-2-2 ID pattern, 97–100 dorsal fin rays, 83–89 anal fin rays, and 52–55 vertebrae. Molecular analysis using mitochondrial DNA Cytochrome Oxidase subunit I sequences showed that specimens of the two species corresponded well to Japanese C. interruptus and Taiwanese S. orientalis, respectively. Therefore, although several reports have raised questions regarding the distribution of C. interruptus and S. orientalis in Korean waters, morphological and molecular data confirm that these two species are indeed distributed in these waters.

• Animal cells and systems
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• 제15권3호
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• pp.251-258
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• 2011

Ciliates are considered one of the most diverse protozoa and play significant roles in ecology. For successful taxonomic study of these microscopic eukaryotes, a staining procedure is necessary, due mainly to intrinsic difficulties in recognizing characteristics from living cells. Although molecular taxonomy has been used to resolve the ambiguities associated with traditional morphology-based taxonomy, extraction of genomic DNA from stained ciliate cells is not available yet. In the present study, we describe a method to extract genomic DNA from a single protargol-impregnated euplotid cell. By using $HgCl_2$ as a fixative and modulating the exposure time of bleach solution in the protargol impregnation, high-quality genomic DNA can successfully be extracted from a stained single cell with minimal loss of morphological integrity. This technique will contribute to the effectiveness of combined approaches of molecular and morphological taxonomy from single ciliate cells.

• 환경생물
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• 제41권4호
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• pp.608-615
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• 2023

The morphological features of germling cells were examined to identify an unspecified resting cyst (described as Cochlodinium cf. polykrikoides-like resting cyst) in the Korean coastal area. LSU rRNA gene sequences were also obtained from a strain established from the germling cells. The resting cysts isolated from Korean coastal sediment were characterized as being brown in color, having a large dark-red body, and fibrous lobed ornaments. The germling cells were ellipsoidal with an irregular outline and had an open comma-shaped ASC (apical structure complex), a wide and deep cingulum, and a deep sulcus. These morphological features were consistent with those of previously described harmful dinoflagellate Pseudocochlodinium profundisulcus. The molecular phylogeny revealed that the germling cells and P. profundisulcus were conspecific. Based on these morphological and phylogenetic data, this study documents the occurrence of P. profundisulcus in a Korean coastal area for the first time.

• ALGAE
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• 제31권2호
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• pp.105-115
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• 2016

The genus Pterosiphonia includes twenty-one currently described species of red algae that occur in temperate to tropical regions of the Atlantic and Pacific Oceans. Pterosiphonia spinifera was originally described as Polysiphonia spinifera from Peru and later transferred to Pterosiphonia. Pterosiphonia spinifera has been reported from Peru as Pterosiphonia pennata, which was originally described from the Mediterranean Sea. Recently, Pterosiphonia arenosa was described based on specimens of P. pennata from Korea. We collected P. spinifera along the coast of Peru and P. arenosa near the type locality in Korea. We compared them with the isotype specimens of P. arenosa using both morphological and molecular data. Our morphological observations and our phylogenetic analysis of rbcL sequences demonstrate that P. spinifera and P. arenosa are conspecific and indicate that P. arenosa is a later synonym of P. spinifera. Our study confirms the wide occurrence of P. spinifera in the western and eastern Pacific Ocean.

• 환경생물
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• 제41권4호
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• pp.666-676
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• 2023

Laurencia is a red algal genus that was described by J.V. Lamouroux in 1813. The main characteristics of this genus have been known as the presence of four pericentral cells in an axial segment, secondary pit connections between adjacent epidermal cells, and the presence of corps en cerise in both epidermal and trichoblast cells. Additionally, the tetrasporangia are arranged in a parallel manner, and male branches feature terminal cup-shaped spermatangial pits. Currently, sixteen Korean Laurencia species have been reported based on their morphological characteristics. In this study, Laurencia decussata and L. pacifica have been added as new records to the Korean algal flora based on a combination of morphological observations and molecular analyses of rbcL sequences. Laurencia decussata has expanded from Australia and New Zealand to Korea, while the distribution of L. pacifica has expanded from USA and Mexico to Korea.

• 식물병연구
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• 제28권2호
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• pp.57-60
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• 2022

Leaves of Chionanthus retusus were found to be damaged by leaf spot disease associated with a fungus in Iksan, Korea. Leaf spots were angular to irregular, vein-limited, scattered, 1-8 mm diameter, brownish-gray to dark brown when dry, with heavy fructification. The pathogen causes premature defoliation of C. retusus plant and was identified as Pseudocercospora chionanthi-retusi based on morphological and molecular-phylogenetic analyses. The phylogenetic tree was constructed using multi-locus DNA sequence data of partial actin (actA), partial translation elongation factor 1-alfa (tef1), partial DNA-directed RNA polymerase II second largest subunit (rpb2) genes, and internal transcribed spacer regions. Current study provides detail morphological description of P. chionanthi-retusi on C. retusus in Korea, with supports of phylogenetic analysis and pathogenicity test.

• 생명과학회지
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• 제19권10호
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• pp.1382-1388
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• 2009

Rubus crataegifolius is a shrub species and is primarily distributed throughout Asia and Europe. We collected 550 representative samples of the eleven populations in Korea to estimate leaf variation within species. The 35 morphological characteristics allowed us to resolve well-supported fixed characteristics and variable characteristics. Sixteen of twenty-three quantitative characteristics and five of twelve qualitative characteristics showed significant differences among populations. We argued that the population differentiation can accounted for the variation in phenetic characteristics such as spine in this species, but were less successful in accounting for variation in other traits. Within a polystatistic leaf structure, their morphological differences could be modulated by ecological pressure such as temperature, altitude, duration of sunshine, and solar radiation. The phenogram showed two distinct clades. One was a group in central Korea and the other was a group in the southern regions of Korea. If morphological characteristics in R. crataegifolius populations reflect their ecological niche, morphology should be regarded with caution as the main criterion for population studies in R. crataegifolius.

• 원예과학기술지
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• 제29권3호
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• pp.240-246
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• 2011

The principal objective of this study was to estimate the availability of morphological data on the basis of the guidelines of the International Union for the Protection of New Varieties of Plants (UPOV) with regard to the identification of the rose germplasm. The correlation of morphological traits and random amplified polymorphic DNA (RAPD) marker data among 44 rose cultivars was assessed via a mantel test. Thirty eight phenotypes were employed for morphological analysis. Sixteen primers were utilized for RAPD analysis, and these generated 225 polymorphic bands. The dendrogram based on the RAPD markersgrouped 44 rose cultivars according to their horticultural types. No significant correlation was observed between the morphological and RAPD marker data. We concluded that current UPOV traits could not be applied to study genetic variation. Further studies on morphological traits are required for the analysis of genetic variation among cultivars.

• 수산해양교육연구
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• 제28권6호
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• pp.1858-1864
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• 2016

Morphological and molecular information of two marine algae collected from Korea is given. One belonging to a green alga, is characterized by small size up to 4 cm high, much branched thalli on all sides, slender and linear branchlets which is constricted near base, axes without prominent branch scars, chloroplasts with a prominent central pyrenoid. The other, as a brown alga, is distinct from other Korean species in having cylindrical elevated projections at all parts of thallus axis, leaves with slightly serrulate margin together with distinct midrib bearing spines and absence to rarely occurred vesicles. In phylogenetic tree based on rbcL sequences, these two species are nested in the same clade with Bryopsis triploramosa and Sargassum polyporum, respectively. In this study, these two species are newly recorded in the Korean marine algal flora based on the morphological and molecular data.