• Research in Plant Disease
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• v.10 no.4
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• pp.279-284
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• 2004

A rust fungus has caused a serious early defoliation of Zanthoxylum schinifolium during growing seasons every year at the plantations located at Hadong and Jinju, Kyeongsangnam-Do in Korea. In order to identify the rust fungus and clarify its life cycle in Korea, aeciospores from Pinus thunbergii were artificially inoculated on the leaves of Z. schinifolium. Uredinial stage was successively formed on the leaves of Z. schinifolium. Based on the artificial inoculation test and on the morphological features of the dried specimens collected from P. thunbergii and Z. schinifolium, this rust fungus was identified as Coleosporium xanthoxyli. Morphological features of aecial and uredinial stages of the species were described. The first symptom of the infection was developed from later June to early July. And leaf infection ratio was 17.8%-58.7% during August at Hadong and Jinju regions of Kyeongsangnam-Do in Korea.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.257-263
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• 2001

Species of the genus Orobanche are parasitic flowering plants, holoparasites, which cling to the roots of green plants. Their tiny seeds (200 x $250\mu\textrm{m}$) germinate in response to chemical stimuli produced by host and some non-host plants. Successful contact with their host leads to development of haustoria for obtaining water and food. The shoots above the ground expose flowers and disseminate seeds. Several samples of Orobanche ramosa, O. crenata, O. cernua, and O. egyptiaca were collected from different localities in Jordan. These samples showed one of the following disease symptoms: dry rot at the base of the stem; general deterioration and expanded lesion from base upward; soft tissue maceration of stem; and black rot of flower parts with incomplete maturation of the ovary and seeds. Isolation from diseased stems and seeds was made on three different mycological media. Several fungi were isolated, mainly, Fusarium spp., Alternaria alternata, Rhizoctonia sp., Dendrophora sp., Chaetomium sp., and an ascomycetus fungus with a perithecium. Pathogenicity tests showed that Fusarium spp. and Alternaria alternata attacked healthy living tissue of Orobanche spikes. These fungi caused lesions of black soft rot and complete deterioration within 5-7 days. They also attacked Orobanche seeds, arresting their germination and causing maceration of non-germinated and germinated seeds after 5-7 days of incubation. Meanwhile, Dendrophora sp. and Chaetomium sp. caused limited lesion at first, but were able to colonize the tissue as it aged and senesced. This study showed the presence of a potential endogenous pathogenic fungi in Jordan, which can be investigated as a biological control for Orobanche.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.2
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• pp.1-16
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• 2020

The current status of geographical distribution range of Deutzia paniculata, one of the korean endemic plants, was investigated based on the species distribution information. The information of the geographical range used for analysis includes all the published references to the distribution of D. paniculata, herbarium specimens in Korea National Arboretum (KH) including its online database: http://www.nature.go.kr, and field research. Although, D. paniculata was firstly recorded in Wonsan, Hamgyeongnam-do, North Korea, this research revelaved that D. paniculata is mainly distributed in Gyeongsangbuk-do and Gyeongsangnam-do, southern regions of the Korean Peninsula. According to the distribution map, this species was estimated on distribution edge of in Anyang region of Gyeonggi-do, Mt. Naejang of Jeollabuk-do and Mt. Taebaek of Gwangwon-do on the distribution edge. However, it was made use of intensive field survey to identify the natural population of the species in these regions. D. paniculata habitat was mainly distributed between 290 meters and 491 meters in altitude, but it was also found ranged from 936 to 959 meters in Gun-wi, Gyeongsangbuk-do, South Korea. The distribution slope was 5° to 35° and the north, N, NE and NW in the aspect. The flora of vascular plants in D. paniculata habitats was listed in 137 taxa: 54 families, 103 genera, 120 species, 2 subspecies, 12 varieties and 3 forms while Korean endemic plants were found in three taxa, Stewartia koreana, Weigela subsessilis and D. Paniculata. Based on a collection of non-biological environment and biological environment data, D. paniculata population were discussed to make strategy and basic research methods for sustainable preservation.

• The Korean Journal of Mycology
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• v.20 no.3
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• pp.204-215
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• 1992

From 12 August to 21 November in 1991, 65 soil specimens were collected from nineteen leguminous plant roots throughout nine locations of four provinces. They were sieved to collect and identify the arbuscular mycorrhizal spores (four genera, 21 species). The species of Glomus were most commonly (47.6% of all observations) found, but the species of Gigaspora (about 4.8% of all observations) occurred infrequently or rarely rather than the species of the other genera. The most common arbuscular mycorrhizal species at nine locations were Acaulospora laevis and Glomus laminated spores cf. macrocarpus var. macrocarpus. All of nineteen legume plant species collected were found to be associated with the arbuscular mycorrhizal fungi . Cassia mimosoides var. nomame and Kummerowia striata in legume plants had the great frequency of arbuscular mycorrhizal fungi associated with their roots. The number of isolated spores were ranged from 0.3 to 10.0 spores per 10g of soil. The species diversity of arbuscular mycorrhizal spores at the disturbed areas were calculated to be bigger than those in the natural vegetation areas.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.201-206
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• 2013

Aporia crataegi, an Korean endangered species, was first analyzed for DNA barcode sequences based on 28-year-old dried specimens and compared barcode characters with 36 individuals of ten geographical populations of Eurasia. They were revealed to consist of five different haplotypes. Among them, haplotype I was mostly extensive and high frequency with 75%. The south Korean individuals were confirmed to be belonging to haplotype I and have no genetic isolation on COI gene. By these results, we consider that selection of the identical haplotype from other geographical populations may be a requirement prior to performing for conservation and restoration of the Korean population. We also propose to analyse the additional genetic markers in order to understand a more accurate genetic structures between haplotypes of this species.

• Parasites, Hosts and Diseases
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• v.51 no.5
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• pp.537-544
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• 2013

The present study was performed to observe histopathological changes in tissues of Bithynia siamensis goniomphalos (Gastropoda, Bithyniidae) incubated in crude extract solutions of camellia (Camellia oleifera) seed and mangosteen (Garcinia mangostana) pericarp, and furthermore to estimate the molluscicidal effects of 2 plant substances. Substantial numbers of bithyniid snails were incubated in various concentrations of 2 plant solution for 24 hr. As the positive control, snails incubated in various concentrations of niclosamide, a chemical molluscicide, were used. The histopathological findings were observed in sectioned snail specimens of each experimental and control groups. The results showed that both camellia and mangosteen extracts had molluscicidal effects at 24 hr with 50% lethal concentration ($LC_{50}$) at concentrations of 0.003 and 0.002 g/ml, respectively, while niclosamide had $LC_{50}$ at concentrations 0.599 ppm. B. siamensis goniomphalos snail tissues (foot, gill, and digestive system) showed disruption of columnar muscle fibers of the foot, reduction of the length and number of gill cilia, numerous mucous vacuoles, and irregularly shaped of epithelial cells. Irregular apical and calciferous cells, dilatation of the digestive gland tubule, and large hemolymphatic spaces, and irregular apical surfaces, detachment of cilia, and enlargement of lysosomal vacuoles of epidermis were also shown in all groups. By the present study, it is confirmed that 2 plants, camellia and mangosteen, are keeping some substance having molluscicidal effects, and histopathological findings obtained in this study will provide some clues in further studies on their action mechanisms to use them as natural molluscicides.

• Korean Journal of Plant Taxonomy
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• v.46 no.3
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• pp.295-300
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• 2016

Sisyrinchium micranthum Cav., a newly naturalized species, was found in Seogwipo, Jeju-do. This species is native to Central and South America and is reported as a widely invasive species around the world. Sisyrinchium micranthum is a sister species of S. rosulatum E. P. Bicknell (Deung-Sim-But-Kkot in Korean), reported as an invasive species earlier in Korea, and both species are members of the subgenus Echthronema. Sisyrinchium micranthum is distinguished from S. rosulatum by the urceolate shape of its flowers and by the large size of its fruits and seeds. Its local name is "Yeon-Deung-Sim-But-Kkot" based on the light blue corolla. We also found that Sisyrinchium angustifolium Mill., previously used for Deung-Sim-But-Kkot, was misapplied. It belongs to the subgenus Sisyrinchium and is morphologically very different from S. rosulatum. We corrected the scientific name of Deung-Sim-But-Kkot by changing it from S. angustifolium to S. rosulatum based on the type specimens, original descriptions, and recent studies.

• Korean Journal of Plant Taxonomy
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• v.43 no.3
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• pp.196-207
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• 2013

As a recent infrageneric classification of Juncus (Juncaceae), Kirschner suggested two subgenera which are distinguished by the type of inflorescence and the absence/presence of bracteole along with 10 sections which are distinguished by the characters of the leaves, the position of the inflorescence, and types of stamens and seeds. However, an intensive morphological investigation on Korean Juncus has yet to be performed. We surveyed the morphological characters of 14 taxa distributed throughout the Korean peninsula, including one North Korean taxon. The quantitative and qualitative characters of rhizomes, leaves, inflorescences, flowers, fruits, and seeds were investigated on each taxon using about 950 specimens of Korean Juncus on loan from major Korean herbaria. As a result, we provide diagnostic characters with illustrations and a key to Korean Juncus.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.31-36
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• 2000

High temperature and pressure materials in power plant are degraded by creep damage, if they are exposed to constant loads for long times, which occurs in the load bearing structures of pressurized components operating at elevated temperatures. Many conventional measurement techniques such as replica method, electric resistance method, and hardness test method for measuring creep damage have been used. So far, the replica method is mainly used for the Inspection of High temperature and pressure components. This technique is, however, restricted to applications at the surface of the testpieces and cannot be used to material inside. In this paper, ultrasonic evaluation for the detection of creep damage in the form of cavaties on grain boundaries or integranular microcracks are carried out. And the absolute measuring method of quantitative ultrasonic velocity technique for Cr-Mo material degradation is analyzed. As a result of ultrasonic tests for crept specimens, we find that the sound velocity is decreased as the increase of creep life fraction$({\Phi}_c)$ and also, confirmed that hardness is decreased as the increase of creep life fraction$({\Phi}_c)$ but the coefficient of ultrasonic attenuation is increased as the increase of creep life fraction$({\Phi}_c)$. Finally based on the result in this paper, it can be recognized that the ultrasonic techniques using velocities and attenuation coefficient factor are very useful non-destructive methods to evaluate the degree of material degradation in fossile power plants.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.57-62
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• 2014

Biting midges (Culicoides: Ceratopogonidae) were collected by Mosquito Magnet$^{(R)}$ traps at the Neutral Nations Supervisory Commission (NNSC) camp and Daeseongdong village inside the demilitarized zone (DMZ) and near the military demarcation line (MDL) separating North and South Korea and at Warrior Base (US Army training site) and Tongilchon 3 km south of the DMZ in northern Gyeonggi Province, Republic of Korea (ROK), from May-October 2010-2012, to determine their seasonal distributions. A total of 18,647 Culicoides females (18,399; 98.7%) and males (248; 1.3%) comprising 16 species were collected. Overall, the most commonly collected species was Culicoides nipponensis (42.9%), followed by C. erairai (29.2%), C. punctatus (20.3%), C. arakawae (3.3%), C. pallidulus (1.8%), and C. circumscriptus (1.4%), while the remaining 10 species accounted for only 1.1% of all Culicoides spp. collected. The seasonal distribution of C. nipponensis was bimodal, with high numbers collected during May-June and again during September. C. erairai was more frequently collected during June-July, followed by sharply decreased populations from August-October. C. punctatus was collected in low numbers from May-September with high numbers collected during October. C. erairai was predominantly collected from the NNSC camp (85.1% of all C. erairai collected) located adjacent to the MDL at Panmunjeom in the northernmost part of Gyeonggi-do (Province), while other sites yielded low numbers of specimens.