• The Korean Journal of Zoology
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• v.8 no.1
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• pp.1-7
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• 1965

The short-necked clam is distributed widely in Korean tidal flats and it is a much an important bivalve quantitatively as to control the production of the tidal flat. The shell of this clam tends to show remarkable morphological variations depending on the habitat. Under a seemingly favorable condition for the growth , the color pattern of shell of the clam is clear and obvious and having less weight and elongated shape, the ratios of shell length to both height and width are small . On the contrary , when the environment appears to be an unfavorable one, the shell is found to be heavy and stunted with smudgy color pattern. If this correlation between could be a basis for the judgement in suitability of growth environment for the clam. In the Ikawazu Bay, Japan, it is revealed that the elongated shell is produced from the coast outside of the Bay (1) , the stunted from the esturay (2) and the intermediate from the floodgate area (3) and the middle of the Bay (4). Followings are the results obtained from the morphological investigation of the claim in this Bay. 1. Relationship between the shell length and the largest shell rib length is linear and between the shell length and the shell width is also linear but with a critical point at the shell length of 17-20 mm. The ratio between the width and the largest rib length at a given shell length increases with the order of 1, 3, 4, and 2. 2. A gradual decreases of the ratio of the shell length to the largest rib length is observed when the former is less than 17-18 mm, and this ratio increases with the shell of longer. Also there is a different range of this ratio in each different location ; the greatest range in 2, the smallest in 1 and 4 being in between. 3. A similar biometric finding is apparent with the ratio between the length and width of the shell and the order in value is 2, 4, 1 and 3. 4. The ratios between the length and the largest rib length of elongated and stunted shell are 0.84-0.86 and 0.89-0.92, respectively , and those between the length and width are 0.40-0.51 and 0.49-0.58, respectively. 5. Generally , the elongated short necked clam shells are products of the tidal flat of good circulation of sea water with high salinity and smaller fluctuations of salinity and temperature within a day. The stunted shells are produced for tidal flats of opposite of above conditions.

• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.67-75
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• 2009

Morphological and genetic variation of Cottus populations in Korea were compared to each other in the watershed. Morphological variation was analyzed by meristic and morphometric characters, and by fertilized egg sizes. Genetic variation was assessed by amplified fragment length polymorphism (AFLP) fingerprinting. Cottus koreanus populations of rivers and streams running towards the eastern coasts of the Korean Peninsula were significantly different in morphometric characters from populations in rivers and streams running towards the western and southern coasts of the Korean Peninsula, but did not differ in meristric characters and fertilized egg sizes. Cottus populations in the upper streams-Yangyangnamadae Stream, Jusu Stream and Samcheogosip Stream-were the same in meristic and genetic characters. However, the Cottus sp. population from Baebong Stream is related to C. hangiongensis in meristic characteristics and to C. koreanus in the morphometric characteristics of length of the ventral fin ray and in the fertilized egg size. Pairwise genetic distances assessed by the AFLP method among C. koreanus populations were in the range of 0.110 to 0.221. Genetic distances between C. hangiongensis and C. koreanus populations varied from 0.542 to 0.621, and those between the Cottus sp. population of Baebong Stream and C. koreanus populations from 0.222 to 0.304. The result of the UPGMA dendrogram shows the Cottus sp. population of Baebong Stream was clearly separated of other C. koreanus populations.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.370-378
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• 2011

To address infra-specific relationships of Sedum kamtschaticum Fisch., and to provide the fundamental information for developing new horticultural variations, we analyzed the morphology of individuals in four natural populations (Mt. Gwangdeok, Mt. Samyeong, Mt. Yonghwa, Tongyeong) and investigated the vegetations of these area. Based on 50 morphological characters the principle component analysis (PCA) has been performed. Principle component axis 1, 2, and 3 explain 22.9%, 14.2%, and 7.4% of total variations, respectively. Dot plot of OTUs in PC2 by PC1 area showed that the areas of four populations are completely overlapped. The result of PCA and the statistics of each character indicate that all of morphological characters are overlapped in these four populations. The maximum deviations are found in the characters related in the size and shape of the leaf. In the vegetation analyses, eighteen community plots that we investigated were grouped into 10 subcommunities: subcomm. Boehmeria spicata, subcomm. Artemisia stolonifera, subcomm. Artemisia keiskeana, subcomm. Impatiens nolitangere, subcomm. Crepidiastrum chelidoniifolium, subcomm. Urtica thunbergiana, subcomm. Artemisia gmelini, subcomm. Commelina communis, subcomm. Erigeron annuus-Artemisia princeps, and typical subcommunity.

• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.163-171
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• 2018

In Korea, Hypodematium glanduloso-pilosum was formerly known as the only Korean native species in the genus. Recently, however, we reported one unrecorded taxon, H. squamuloso-pilosum Ching, which was found on rocks at a limestone mountain in Yeongwol, along with one new taxon, H. angustifolium in Okcheon. Traditionally, Hypodematium taxa are often distinguished from each other by vegetative characters such as pinnatifid lamina, glandular hairs, and narrower or linear lanceolate scales on stipe bases. H. glanduloso-pilosum, distributed widely throughout the country except on Jejudo Island in Korea, exhibiting variations in leaf segregation, indusia positions, hair distributions and size. The high variation in the morphological characters in the widely distributed taxon has caused problems delimitating three native species from each other. To evaluate the phylogenetic relationships among H. glanduloso-pilosum and taxa related to Hypodematium (all Korean native taxa), we carried out morphological and molecular analyses (cpDNA rbcL and psbA-trnH) of populations of the genus Hypodematium in Korea. Although H. glanduloso-pilosum exhibits high variations in some morphological characters, the species is characterized by stipes and indusia with densely multicellular hairs and rod-shaped glandular hairs or hairs and lanceolate or oblong lanceolate scales in rhizomes and stipe bases distinguished from those of other Korean native taxa (H. squamuloso-pilosum and H. angustifolium). In the analyses of cpDNA data, three Korean native taxa are placed in the same clade, i.e., in the glanduloso-pilosum group. Moreover, our analyses propose that H. squamuloso-pilosum (China and Korea), H. angustifolium (Korea), and H. fordii (China and Japan) share the same glanduloso-pilosum clade with H. glandulosopilosum (China, Korea, and Japan).

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.413-418
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• 2010

A total of 424 plants was regenerated from the seed-culture of a rice cultivar, 'Ilpum'. The regenerated plants were grown in a greenhouse. The 297 plants with high fertility were selected among 424 plants. The harvested seeds from each plant were planted to each line at experiment field in 2008 and 2009. The each line was evaluated for the agronomic and morphological traits, also. The 64 lines (21.5%) showed significant differences in agronomic and morphological traits from donor cultivar 'Ilpum' among 297 lines. The heading date different from donor cultivar 'Ilpum' showed highest frequency in 297 lines, and accounts for 9.1% (29 lines). The phenotype of opaque endosperm and rolling leaf account for 1.7% and 1.3% in 297 lines, respectively. The genetic segregation was observed in dwarf/semi-dwarf, rolling leaf and opaque endosperm at $S_1$ generation, but not in $S_2$ generation. These results suggest that the mutant derived from a tissue-culture will be one of the promising genetic resources, due to its wide variation and high frequency of mutation, comparatively.

• Journal of the Korean Wood Science and Technology
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• v.15 no.3
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• pp.1-13
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• 1987

This study was carried out to investigate the variations of dimension and exterior shape of vessel elements, morphology of spiral thickening and ray-vessel pit in korean diffuse-porous woods (56 species, 18 families), The tangential pore diameter and vessel element length was increased, whereas the pore number per unit area($1mm^2$) was decreased from pith outwards. The tangential pore diameter was decreased but the length of vessel element was not changed from earlywood to latewood within an annual ring. However, the dimensional variations of vessel element was not able to be recognized among relative positions in peripheral variation. The exterior shape of vessel element could be classified into four types; Type 1 is without tail, Type 2 with ligulate tail, Type 3 with broad taper tail and Type 4 with the very short length between perforations. The distribution frequency of Type 2 and 3 was relatively high in comparision with the others. According to the prominence, distribution position and branched shape, the spiral thickenings could be divided into five types. The spiral thickenings occurred 52% in the species observed. Thus it was doubtful to consider the simple presence of spiral thickening as diagnostic index in diffuse-porous woods. The morphology of ray-vessel pit could be grouped as reticulate, scalariform, oval, linear and coalescent type. Most of species examined showed oval and linear type.

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.39-45
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• 2017

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.11-16
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• 2011

This study was conducted to identify the morphological characteristics and variations level by site environment of native bermudagrass (Cynodon spp.) from costal and island region in South Korea. Soil chemical properties and morphological characteristics were investigated. There were significant differences in plant height, leaf width, leaf length, cotton on leaf blade, stolon, and number of seed per spike depending on where they were collected from natural habitat. We have discovered a variety of variation among the investigated traits in Korean native bermudagrass ecotypes. There were broad leaf and fine leaf types of native bermudgarass in S. Korea. Adaptability was in very high on inadequate environment in bermudagrass with broad leaf types, it has also been suggested that management worth in terms of use. These results may provide basic information for bermudagrass breeding development and the collected types during this investigation would be worth being preserved as genetic resources for further breeding purposes.

• Korean Journal of Plant Resources
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• v.33 no.1
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• pp.40-49
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• 2020

The objectives of this study were to evaluate total phenolic content (TPC) and individual phenolic compounds in leaves of perilla genetic resources, assess whether they could be used as distinguishing factor among germplasms, and evaluate their relationship with some quantitative and qualitative morphological characters. TPC and individual phenolic compounds were determined using Folin-Ciocalteu method and UPLC-PDA system, respectively. Wide variations in TPC (7.99 to 133.70 mgGAE/g DE), rosmarinic acid (ND to 21.05 mg/g DE), caffeic acid (ND to 1.17 mg/g DE), apigenin-7-O-diglucuronide (ND to 2.21 mg luteolin equivalent (mgLUE)/g DE), scutellarein-7-O-glucuronide (ND to 5.25 mg LUE/g DE), and apigenin-7-O-glucuronide (ND to 2.81 mg LUE/g DE) were observed. Intensities of green pigment at abaxial and adaxial leaf surfaces were positively correlated with phenolic compounds whereas leaf length and width had negative correlation. Purple pigmented accessions were shorter in leaf length and width but exhibited higher amount of phenolic compounds compared to green pigmented accessions in most cases. Leaf shape was not related with content of phenolic compounds, color of leaves, and length/width of leaves. TPC and individual phenolic compounds along with morphological characters could be useful distinguishing factors for perilla genetic resources.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.84-92
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• 1985

This experiment was carried out to study the morphological traits, yield and yield components of barley cultivars - Kangbori, Olbori and Suwon 18 - on different seeding dates. It appeared generally rapid development of young spike from late stage of floret differentiation (X stage) to complete it at heading stage. Young spike appeared more influencials by the different seeding dates rather than years and cultivars. Stem started the development from late stage of spikelet differentiation (VII stage) to early stage of floret differentiation (IX stage), indicating the continuing development from basal to upper internodes. Number of spikes per unit area showed more effect in seeding date rather than cultivar and year. However, number of kernels per spike and 1,000 kernel weight affected more due to years rather than cultivar and seeding date. It was significantly difference in grain yield according to different seeding dates.