• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.686-692
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• 2010

This study described the general pattern of genetic variation among ten teak (Tectona grandis Linn. f.) provenances in Myanmar and determined the most suitable seed sources for the plantation program in Bago Yoma region. Seeds of ten provenances were collected to cover the whole teak natural distribution in Myanmar and planted at four trial sites in Bago Yoma region in 1998. Seven years after planting, variation was assessed for growth, morphological characteristics and their correlation with geoclimatic factors. Statistical analysis using ANOVA revealed that there were significant differences in most of the traits measured among provenances, trial sites and provenance ${\times}$ site interaction at five percent level. A positive significant correlation (p<0.01) was found among most of the traits. The regression analyses between all traits and geoclimatic factors indicated the existence of ecoclinal variation in teak. Most of the traits were negatively correlated with the latitude while a positive significant correlation was found between longitude and C/B ratio, crown-diameter, average branch angle and leaf-remain. There was no significant correlation between the mean temperature and any other traits in this study. Furthermore, growth traits and crown diameter were positively correlated with the mean annual rainfall while negative correlation was found between the geographical distance and growth traits. Results indicate that the latitudinal pattern of teak genetic variations in growth performance was attributed to the limit of mean annual rainfall. Comparative assessment showed that local provenances were generally the best and could be use as suitable seed sources for the plantation program in the Bago Yoma region.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.1-8
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• 1995

The relationships between aphids, plants, other organisms and some physical components of the environment are reviewed. Aspects considered include year cycles, polymorphism fecundity, relationship of different groups of aphids with particular groups of plants, honeydew, alarm pheromones, aposematic colouring, camouflage, colour variation within species, morphological variation within species, multivariate analysis and problems of its interpretation, parasitism, stridulating mechanisms, predators, coevolution of plants and aphids, plant galls, trapping aphids and the interpretation of trap catches, an curation of aphid collections. References are given to sources of information about aphids, with special reference to the Korean fauna.

• The Plant Pathology Journal
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• v.33 no.2
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• pp.109-117
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• 2017

Tan spot caused by the fungus Pyrenophora triticir-repentis is a serious disease of wheat, which is on increase in recent years in Mediterranean region. In the field this fungus produces a diamond-shaped necrotic lesions with a yellow halo on wheat foliage. The objective of this study was to characterize and compare several monospore isolates of P. tritici-repentis collected from different infected wheat fields in various locations of Algeria, and find the morphological differences between them, if any. The results revealed wide morphologically variation among the isolates based on colony colors and texture, mycelial radial growth and conidial size.

• Journal of the Korean Society of Costume
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• v.21
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• pp.87-99
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• 1993

The fiber morphologies of the textiles from the burials of the Seip group of Ohio Hopewell (ca. 100 B.C. to A.D. 500)mounds were examined using light and scanning electron microscopy. A theoretical model was proposed which delineates the rate of morphological change in fibers through time and the cultural activities which occur during the life of a textile element. The Seip textiles were categorized according to their visual and structural characteristics. The microscopic examination of the Seip textiles yielded the evidence of animal hair fibers and bast fibers. The animal hair fibers of the seip textiles were identified as the hair of rabbit or hare. The bast fibers of the Seip textiles exhibited variation in morphological features such as the degree of bundle separation and the presence of transverse striations, fibrillations, or trans-verse cracks.

• Journal of Species Research
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• v.13 no.1
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• pp.41-49
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• 2024

Chironomus is a large genus of Diptera comprising about 400 species and occurs worldwide except for Antarctica. The strong morphological cross-taxon similarity of chironomid larvae renders identification at the species level difficult. Here, we analyzed the morphology of larvae of Chironomus flaviplumus, an easily cultured species employed as a bioindicator in polluted environments, to determine identifying morphological characteristics at the first through fourth instar. Observed differences appearing at each instar include the presence or absence of setae on the body and tubules on the 10^th and 11^th body segment, the number of seta interna in the mandible, and the presence or absence of ring organs in the antennae. Some specific morphological characteristics did not change after hatching. Our findings provide a reliable method for identifying C. flaviplumus larvae.

• Korean Journal of Plant Resources
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• v.30 no.6
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• pp.590-600
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• 2017

A total of 447 accessions consisting of seven Brassica spp.; Brassica carinata (34), B. juncea (199), B. rapa subsp. dichotoma (18), B. rapa. subsp. oleifera (14), B. rapa subsp. rapa (36), B. rapa subsp. trilocularis (56) and B. alba subsp. alba (90) were studied for their morphological characters and fatty acid compositions. There was a wide variation for morphological traits, oil content and fatty acid composition among Brassica species. Seed number/silique and yield/plant were varied from 4.2 (B. alba) to 25.1 (B. rapa subsp. trilocularis) and from 170.7 g (B. rapa subsp. oleifera) to 351.9 g (B. juncea L. Czern.), respectively. Among Brassica species, B. rapa subsp. trilocularis exhibited the highest oil (29.2%), stearic (20.4%) and erucic acid (45.3%) content. B. carinata had the highest content of palmitic (5.2%), oleic (21.2%) and linolenic acid (11.1%). B. rapa subsp. dichotoma and B. rapa subsp. oleifera exhibited the highest content of linoleic (8.1%) and behenic (26.9%) acid, respectively. B. rapa subsp. trilocularis exhibited the highest (45.3%) erucic acid content and significant positive relationship was observed between oleic acid and linoleic acid. This variation of agronomic and fatty acid compositions in Brassica species can be utilized to develop new varieties.

• Journal of Korean Dental Science
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• v.11 no.1
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• pp.1-4
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• 2018

Purpose: The aim of this study was to evaluate the ossification and maturation of the midpalatal suture in young Koreans using cone-beam computed tomography (CBCT). Materials and Methods: The study sample consisted of 40 patients with ages from 8.2 to 23.6 years who visited the Department of Orthodontics, Chung-Ang University Dental Hospital. CBCT images were taken for diagnosis. From the CBCT image, morphological stages and Hounsfield units (HU) of midpalatal suture were obtained to evaluate the midpalatal suture maturation. Spearman's correlation coefficients were calculated to analyze relationships between chronological age, morphological stage, and HU. Result: There was a wide variation in the morphology of the midpalatal suture in each age group. It showed a modest relationship between the chronological age and the degree of morphological stages. Also there was a modest relationship between the chronological age and HU. In contrast, there was a significant relationship between morphological stages and HU of midpalatal suture (P<0.01). Conclusion: CBCT images can be used for the evaluation of midpalatal suture maturation. For the estimation of the prognosis of rapid maxillary expansion, CBCT may be reliable for the assessment of the maturation of the midpalatal suture.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.68-68
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• 2017

The status of corn genetic diversity in the uplands of Sarangani in Southern Philippines was investigated using 12 morphological traits subjected to multivariate statistical analyses. Information about traditional farming, post-harvest and storage practices were also elicited especially in relation to losses of traditional varieties, a phenomenon known as genetic erosion. While a handful of farmers still plant traditional corn varieties in the remotest areas, a significant number had already shifted to genetically modified corn. Furthermore, principal component analysis (PCA) reduced the 12 morphological traits into 5 principal components and identified ear length and ear weight to be major contributors to variation. Cluster Analysis, on the other hand, formed two distinct groups but failed to give information about intra-cluster variability among the 32 collected corn accessions. These results warrant that more informative morphological traits and that molecular markers will be used to obtain a better picture of genetic diversity in Sarangani upland corn. Molecular analysis is also needed to establish genetic identities of these cultivars and to detect gene introgression from GM varieties into the gene pool of farmers' corn varieties. These analyses are imperative for the conservation of traditional corn varieties before they disappear in the Sarangani uplands because of shifting priorities of upland farmers.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.353-362
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• 2014

In this study, we investigated the effect of geographical variations on Sargassum thunbergii morphology to make a taxonomic reconsideration about infraspecific taxa in this species. In order to examine the morphological characteristics of S. thunbergii, total 27 matured and morphologically intact thalli were collected from the east, west and south coast in spring 2011. Interestingly, it was observed that the species populations on the west coast were characterized by short, thin and coarse thallus, and soft texture. However, the populations on the east coast showed thicker thallus, larger leaf and vesicle, and tougher texture. Thallus height of S. thunbergii was found to be similar at both east and west coast. Further, the height of the thallus and lateral branch of the species populations residing south coast were highest whereas the size of leaf and vesicle are shortest, in comparison with east and west coast species. Although morphological characteristics of the north east coast populations corresponded to the original description of S. thunbergii f. latifolium, we could not find exact morphological features and diagnostic characters to distinguish form in S. thunbergii. These results indicated that it is not the optimal characteristics to identify infraspecific form in this species. In contrast, morphological variations may signify the adaptation of this species to local environmental factors. Thus, we recommend that intraspecific morphological variation of S. thunbergii should be carefully used to identify infraspecific taxa.

• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.121-121
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• 2005