• Journal of Plant Biology
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• v.39 no.1
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• pp.23-29
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• 1996

Morphology and reproduction of Polysiphonia atlantica Kapraun et J. Norris were studied on the basis of field and laboratory cultured materials collected from the coast of Korea. The plants consisted of prostrate and erect axes with an extremely soft flaccid texture. Axes were ecorticated and had four pericentral cells. The plants except for female gametophytes had few trichoblasts. Branches in the upper portion of the thallus grew to the same level, resulting in a flat-top form. Tetrasporangia were arranged in straight series. Spermatangial branches replaced whole trichoblasts and had a 1-2 celled serile tip. The procarp had a four celled carpogonial branch. After fertilization, the carpogonium contancted the surface of the supporting cell. The formation of the auxiliary cell from the supporting cell was somewhat delayed P. atlantica from Korea was similar to P. subtilissima Montagne in some features. However, the taxonomic differences between the two species were identified in the development of branches and the number of sterile cells at the tip of spermatangial branches.

• Korean Journal of Plant Taxonomy
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• v.49 no.2
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• pp.101-106
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• 2019

A pollen morphological study was conducted using light and scanning electron microscopy involving six species belonging to the subtribe Neoguillauminiinae. Pollen samples from the six species are tricolporate, and the colpi are surrounded by broad margo, with the widest width in the equator, narrower toward the pole, and rounded at the end. Based on the pollen morphology, pollen of the species in the subtribe Neoguillauminiinae were divided into four types: the Neoguillauminia type (T1), the C. collinus type (T2), the C. casuarinoides type (T3) and the C. paucifolius type (T4). The generic divergence between Neoguillauminia and Calycopeplus was supported by the pollen characters of the size, amb and lumina shape. In particular, the traits of rounded shape in the outline of the polar view and circular lumina, which appear only in the pollen grains of N. cleopatra, support the recognition of Neoguillauminia as a monotypic genus. Calycopeplus oligandrus and C. paucifolius had the same reticulate pattern of pollen grains, supporting Forster's hypothesis that these two species are closely related. On the other hand, the close relationship between the morphologically similar C. collinus and C. casuarinoides was not supported by the pollen characters. Within the subtribe there are two equally parsimonious hypotheses regarding the evolution of exine characters. The first consists of two changes of microreticulate through parallel evolution from the primitive reticulate exine, and the second is that the microreticulate pattern is differentiated from the reticulate state and then reversed to reticulate pollen grains.

• Journal of Plant Biology
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• v.28 no.3
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• pp.217-224
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• 1985

Because Ceramium fastigiatum Harvey (1834) is a later homonym of C. fastigiatum Roth (1806), a quite different plant from the former, it becomes illegitimate and must be rejected under the Article 64 of International Code of Botanical Nomenclature. For this reason, we suggest to give a new name, Ceramium fastigiramosum Boo et Lee, to the former species, keeping the original specific epithet‘fastigiatum’. The morphology of vegetative and reproductive structures is re-examined. The life history is confirmed as a Polysiphonia-type in laboratory culture.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.83-85
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• 2005

Ditylenchus acris was isolated from diseased strawberry plants. Frequently, D. acris and Aphelenchoides fragariae occur together in a strawberry plant. Both species appeared very similar in the shape, length, swimming behavior and causing symptoms, and difficult to distinguish them by a stereomicroscope. But they were easily distinguished under a compound microscope especially by their tail shape, median bulb, vulva position, and bursa.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.95-95
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• 2004

• Korean Journal of Plant Taxonomy
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• v.50 no.4
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• pp.413-418
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• 2020

A new variety, Lecanorchis japonica var. insularis (Orchidaceae: Vanilloideae), a mycoheterotrophic orchid from Jejudo Island, Korea, is described and illustrated. It usually grows with L. japonica var. japonica, L. japonica var. hokurikuensis and L. kiusiana in evergreen forests. The newly described variety is distinguished from L. japonica vars. japonica, hokurikuensis, and kiiensis by having fully opened, larger flowers and an obtuse labellum apex.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.1
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• pp.125-128
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• 2021

This paper presents the root cause failure analysis of the circulating water pump in the 560 MW thermal power plant. A fractured austenitic stainless-steel shaft operated for 24 years was examined. Fracture morphology was investigated by micro and macro-fractographic analysis. The metallurgical analyses including chemical analysis, metallography and hardness testing were performed. The analysis reveals that the pump shaft was fractured due to the reverse bending load with combination of rotating bending load. Corrective actions for plant operator was recommended based on the analysis.

• Mycobiology
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• v.29 no.2
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• pp.104-106
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• 2001

Alternaria cassiae Jurair & Khan was recorded on seeds of sickle senna(Cassia tora L.). Seed infection ranged from $25{\sim}45%$ in two samples. Developing roots and shoots turn brown and died in case of severe infection. Detailed descriptions were given on the habit characters of the fungus and on the morphology of conidiophores and condia. This is the first report of A. cassiae on seeds of Cassia.

• Journal of Plant Biology
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• v.34 no.3
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• pp.229-238
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• 1991

The main objective of this study was to clarify the taxonomic status and the speciation mechanism of Viola albida complex in Korea. The complex includes three very closely related taxa, taxonomic ranks of which are much in dispute. These taxa in the complex are sympatric in distribution, and they are very similar in most morphological characteristics. Comparative morphological analyses revealed that they can be distinguished on the basis of leaf shape, although they show complicated patterns of variation in leaf shape. The variation of leaf shape in each taxon appeared to be maintained through developmental process, and extensive cleistogamy and vegetative reproduction in these taxa are suggested as the mechanisms maintaining the variation. Genetic variation in this complex was monomorphic in all 14 loci examined. Palynological study also showed that these taxa have the same pollen morphology. These results strongly suggested that they should be recognized as varieties of V. albida; var, albida, var. chaerophylloides, and var. takahashii. The results also suggested that some individuals that can be assigned to var. takahashii might be hybrids between var. albida and var. chaerophylloides.

• Journal of Plant Biology
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• v.35 no.4
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• pp.339-358
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• 1992

The bark morphology and anatomy of six species in Korean gymnosperms were examined with light and scanning electron microscopes. The species were Thuja orientalis (Cupressaceae), Ginkgo biloba (Ginkgoaceae), Cyeas revoluta (Cycadaceae), Pinus koraiensis (pinaceae), Taxus cuspidata (Taxaceae), Cryptomeria japoniea (Taxodiaceae). We described the bark features such as surface colour, thickness, depth of inner and outer bark. presense or absence and features of expansion tissue of ray, composition of periderm, and component cells of secondary phloem. The comparison with these features showed significant differences among all six species. Furthermore. it was suggested that sclereids types and sieve area shapes in sieve cells might be useful to the comparative morphological studies of gymnosperms.sperms.