• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2159-2170
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• 2016

Many plant-pathogenic bacteria are dependent on quorum sensing (QS) to evoke disease. In this study, the population of QS and quorum quenching (QQ) bacteria was analyzed in a consecutive monoculture system of Pseudostellaria heterophylla. The isolated QS strains were identified as Serratia marcescens with SwrIR-type QS system and exhibited a significant increase over the years of monoculture. Only one QQ strain was isolated from newly planted soil sample and was identified as Bacillus thuringiensis, which secreted lactonase to degrade QS signal molecules. Inoculation of S. marcescens to P. heterophylla root could rapidly cause wilt disease, which was alleviated by B. thuringiensis. Furthermore, the expression of lactonase encoded by the aiiA gene in S. marcescens resulted in reduction of its pathogenicity, implying that the toxic effect of S. marcescens on the seedlings was QS-regulated. Meanwhile, excess lactonase in S. marcescens led to reduction in antibacterial substances, exoenzymes, and swarming motility, which might contribute to pathogensis on the seedlings. Root exudates and root tuber extracts of P. heterophylla significantly promoted the growth of S. marcescens, whereas a slight increase of B. thuringiensis was observed in both samples. These results demonstrated that QS-regulated behaviors in S. marcescens mediated by root exudates played an important role in replanting diseases of P. heterophylla.

• Journal of Plant Biotechnology
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• v.47 no.2
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• pp.150-156
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• 2020

Weeds play an important role in the survival of viruses and are potential inoculum sources of viral diseases for crop plants. In this study, specimens of Pseudostellaria heterophylla exhibiting symptoms of the cucumber mosaic virus (CMV) were collected in Bonghwa, Korea. The characteristics of the disease were described and leaf RNA was extracted and sequenced to identify the virus. Three CMV contigs were obtained and PCR was performed using specific primer pairs. RNA from positive samples exhibiting CMV leaf symptoms was amplified to determine the coat protein. A sequence comparison of the coat protein gene from the CMV BH isolate shared the highest nucleotide identity (99.2%) with the CMV ZM isolate. Phylogenetic analysis showed that CMV-BH belonged to subgroup IA and that the most closely-related isolate was CMV-ZM. All test plants used for the biological assay were successfully infected with CMV and exhibited CMV disease symptoms such as blistering, mosaic, and vein yellowing. To our knowledge, this is the first report of CMV infection in P. heterophylla from Korea.

• Korean Journal of Plant Taxonomy
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• v.45 no.2
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• pp.109-113
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• 2015

Fieldwork in Lao PDR during 2007-2008 resulted in the discovery of 15 unrecorded fern species among the flora of Lao PDR. All have been identified in other countries in southeastern Asia, as well as from other tropical areas. The species are as follows: Asplenicaceae (Asplenium delavayi, A. rockier), Athyriaceae (Anisocampium cuspidatum), Dennstaedtiaceae (Microlepia hookeriana, Pteridium revolutum), Dryopteridaceae (Didymochlaena truncatula, Dryopteris cochleata, Polystichum biaristatum, P. lindsaefolium), Gleicheniaceae (Dicranopteris curranii), Hypodematiaceae (Hypodematium crenatum), Lindsaeaceae (Lindsaea heterophylla), Pteridaceae (Pteris decrescens), Polypodiaceae (Pyrrosia nummularifolia) and Thelypteridaceae (Cyclosorus dentatus).

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.3
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• pp.159-163
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• 2002

This study was analyzed to photosynthetic pigment concentrations and changes of SOD activities on seven species of liana of A. heterophylla, P. scandens, V. thunbergii, P. tricuspidata, C. trilobus, L. japonica and T. kirilowii, and two species of E. arvense and A. princeps of non climbing plants. Concentrations of chlorophyll a and b, total chlorophylls and total carotenoids of P. tricuspidata in 100 ppb ozone site were the most increased. It was the most increased to P. scandens in ratio of chlorophylls and carotenoids, and E. arvense in ratio of chlorophyll a and b. There was difference to ratio of chlorophyll a and b of liana and non liana. At ratio of chlorophyll a and b of 100 ppb ozone site and the control it was more sensitive to chlorophyll a than chlorophyll b, and P. tricuspidata was the most sensitive at comparing with species, and it was more sensitive to liana than non liana. In SOD activities A. princeps was the most increased to 3535.7 unit/g, and P. scandens was the fewest increased to 109.3 unit/g, and A. heterophylla was only decreased to 131.7 unit/g in comparing to 100 ppb ozone sites and the control.

• Journal of Life Science
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• v.27 no.1
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• pp.89-94
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• 2017

DNA sequences of the intergenic spacer 1 and intergenic spacer 2 of the nineteen plants belonging Vitis genus were collected from the Genbank. DNA sequences of the same regions of Vitis thunbergii var. sinuata and Ampelopsis brevipedunculata var. heterophylla, both common plants in Korea, were not available in Genbank. Those two plants were collected, their genomic DNA encoding 18S rRNA, intergenic spacer 1, 5.8S rRNA, intergenic spacer 2 and part of 28S rRNA amplified and DNA sequence determined. DNA sequences of twenty-one plants including two Korean plants were aligned by the Multiple sequence comparison by log-expectation(MUSCLE) algorithm and the alignment was used to calculate neighbor-joining tree and pairwise distance. The results indicate DNA sequences of the two Korean plants are highly homologous with each other, but they are quite distantly related to the other Vitis plants. Distant relationship of the two Korean plants with the other Vitis plants might be due to independent evolution of those two plants in geographically isolated environment. Those two Korean plants are classified in different genera based on the morphology, one in Vitis genus and the other in Ampelopsis genus, providing another example of discrepancy between morphological and genetic classification.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.188-194
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• 2000

This study was carried out to obtain the optimum cultivation conditions of wild ornamental plant resources, Dicentra spectabilis L. The altitude of the habitat was ranged from 630m to 690m in Mt. Gujeol. Most of the habitat faced toward the northeast aspect and the gradient was ranged from 25 to 33 degrees. The light intensity of Dicentra community was 14,000lux on the average, and it was tendency to decrease by foliation of other woody plants. The appearance number of Dicentra per quadrat was 30 individuals on the average, and total appearance species in all quadrat surveyed was 52 taxa. Among them, Quercus mongolica, Lindera obtusiloba, Corylus heterophylla, Cornus controversa, woody plants, Corydalis speciosa, Pseudostellaria heterophylla, Artemisia keiskeana, Dryopteris crassirhizoma, Arisaema amurense var. serratum, Carex siroumensis, and Chloranthus japonicus, herbaceous plants, were showed as dominant species. Soil acidity in the habitat was 5.15 to 5.96, and average content of soil moisture was 32.6%. The contents of average organic matter, $P_2O_5$, K, Ca, and Mg were 1.99%, 14mg/kg, 0.55me/100g, 15.2me/100g, and 3.3me/100g, respectively. Electron conductivity was ranged from 0.50 to 0.76dS/m. Also, the average air temperature of May and June was 14.2$^{\circ}C$ and 19.4$^{\circ}C$, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.3
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• pp.81-92
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• 2019

This study was conducted to establish vegetation structure characteristics and vegetation management plan of the cultural landscape forests located around Unmun Temple in Cheongdo-gun and to provide the basic data needed to manage the cultural landscape forests. The landscape characteristics are analyzed in two perspectives including the landscape as viewed from inside and outside of Unmun Temple and eight landscape views are selected. Main views are Pinus densiflora forest and Abies holophylla forest around Unmun Temple. As a result of the survey of existing vegetation around Cheongdo-gun Unmun Temple, P. densiflora forests and P. densiflora-A. holophylla forests are widely distributed, occupying 79.2% of the forest. The plant community structure was classified into seven types according to the three topographic characteristics, flat forests, slope forests, and lower forests, Which were divided into a total of 30 survey plots and the average relative importance percentage was determined. The P. densiflora community on the flat are dominated by Carpinus tschonoskii in Under-canopy. The P. densiflora-A. holophylla community on the flat had a relatively high rate of domination in the shrubs. There were no competing species for the A. holophylla community on the plat. The large standard P. densiflora and the small standard P. densiflora were expected to be confined by P. serrulata var. pubescens and the Quercus variabilis on the slopes. The managed P. densiflora community had a relatively high rate of P. densiflora domination in the shrubs. The P. densiflora community on the lowland was dominated by Styrax japonicus and P. serrulata var. pubescens. The Shannon species diversity index was 0.2360 to 1.4088. The results of the correlation analysis with P. densiflora, A. holophylla and other species were P. densiflora had negative correlation with Acer mono, Corylus heterophylla var. heterophylla, Zelkova serrata and A. holophylla, and A. holophylla have negative correlation with S. japonicus and P. densiflora. Landscape characteristics and plant community structures are analyzed to propose management methods of maintaining and restoring The P. densiflora and A. holophylla cultural forest landscapes around Unmun Temple.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.258-266
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• 1998

The purpose of this study is to investigate the actual conditions, to find problems, and to present an improvement plan of interior landscape in the subway stationis. Moreoiver, it will presume the possibilties to develop the subway and ways to utilie underground space effectively. The results are summarized as follows A light intensity was recorded 0-100 Lux as the lowest light and 500 Lux below as the highest in 61 subway stations. An average temperature of 12 $^{\circ}C$and an air humidity of 38% were recorded over a 4 month period from January to April, but includes a drastic variaton between -8.5$^{\circ}C$ and 21.5$^{\circ}C$. Soil acidity of pH 7 below and soil moisture of 1-2 wet degree were apeared in subway stations mostly. Plant forms consisted of artificial flower & flower. Plant species were recorded at a total of 54 species and appeared in the order of Araucaria heteropylla, Ophiophogon jaburan, Aspidistra elatior cv. 'Asahi' and Hedera helix. Plant height was, for the most part, below 0.5m. Plant species that was fined of conditions were Palm, Camellia japonica, Araucaria heterophylla as a high plant, dracaena fragrans, dracaena deremensis cv. Wakneckii as a middle plant, and Ophiopogon jaburan, Hedra helix, ytomium falcatum, Aspidistra elatior cv. Asahi as a low plant. It used to water materials such as small pool, small cascade, water cycles and natural materials such as natural rock, small rock, sand, bark and animal materials such as squirrels, birds, goldfish as an object for plants in the subway stations. From these actual conditions, First of all, It must make up physical environments such as light, temperature humidity, soil for plant growth, and is important to chooce suitable indoor plants and draw up systematic management in the subway environments. Also, it change plants frequently and uses variable objects for subway stationi individuatism, Moreover, indoor plants with strong environmental adaptation abities such as shade tolerance, drought tolerance and cold tolerance need to develope variable species possibly. If these improvements occur, utilization and amenity of subway stationis will increase, according to the use of interior landscape.

• Korean Journal of Plant Taxonomy
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• v.49 no.2
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• pp.145-178
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• 2019

The genus Pseudostellaria (Caryophyllaceae) in Korea was investigated in order to clarify the taxonomic positions and scientific names among the species in this genus based on morphological characteristics. P. ${\times}$ bohyeonsanensis and P. ${\times}$ seoraksanensis share several characteristics (trichome on the sepal margin and midvein, five petals, and stem reclining to the ground after flowering) with P. davidii. P. ${\times}$ bohyeonsanensis, resulting from natural hybridization of P. davidii and P. okamotoi var. longipedicellata, has sterile fruit and a long pedicel (2.2-6.0 cm). P. ${\times}$ seoraksanensis, a natural hybrid of P. davidii and P. palibiniana var. palibiniana, has sterile fruit and a short pedicel (1.1-1.8 cm). P. okamotoi var. longipedicellata shares several characteristics (long pedicels of chasmogamic flowers that elongate to the ground when bearing fruit and cleistogamic flowers with a long pedicel) with the related taxa P. okamotoi var. okamotoi. P. okamotoi var. longipedicellata has slender root tubers, glabrous pedicels, and 5-9 petals. P. palibiniana var. gageodoensis is described from Gageodo Island. It is similar to P. palibiniana var. palibiniana having chasmogamic flowers at the stem terminal, 5-7 petals, and a short pedicel, but P. palibiniana var. gageodoensis is distinguished by 1-2 rows of trichomes on the pedicel, a large sepal size, a large petal size, and a branched stem at its base. P. ${\times}$ biseulsanensis, from a natural hybrid of P. heterophylla and P. okamotoi var. longipedicellata, has a solitary aerial stem, a chasmogamic flower at the stem terminal, a shallow marginate or bitten petal apex, one row of trichomes on the pedicel, and sterile fruit. P. ${\times}$ segeolsanensis, from a natural hybrid of P. palibiniana var. palibiniana and P. okamotoi var. okamotoi, is described from Segeolsan Mt. It has numerous aerial stems, a chasmogamic flower at the stem terminal, 1-2 rows of trichomes on the pedicel, and fertile fruit. Consequently, the genus Pseudostellaria in Korea has been classified into eight species, four hybrids, two varieties, and five forms.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.220-229
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• 2017

This study was carried out to investigate the forest community classification and vegetation structure in NYNRF(National Yonghyeon Natural Recreation Forest). We studied by 26 plots($20{\times}20m$) from April to September 2014. NYNRF were classified into the Quercus mongolica Community, Quercus variabilis community and Acer pictum community in the 3 community units. The Q. mongolica Community was subdivided into the Pinus densiflora group and Typical group and A. pictum community was also subdivided into the Euonymus sachalinensis group and Typical group. NYNRF were classified into 3 communities and 4 groups and 5 VU(vegetation units). According to the result of importance value analysis between vegetation units, VU 1 P. densiflora(65.1%), VU 2 Q. mongolica(73.6%), VU 3 Q. variabilis(75.1%), VU 4 E. sachalinensis(33.3%) and VU 5 Lindera erythrocarpa(27.1%) were highly showed in tree layer and VU 1 Rhododendron mucronulatum (19.3%), VU 2 Calamagrostis arundinacea (16.9%), VU 3 Indigofera kirilowii (75.1%), VU 4 and VU 5 Pseudostellaria heterophylla(each other 14.8% and 24.7%) were highly showed in herb layer. In INSPAN(INdicator SPecies ANalysis) of vegetation units, 33 species were analyzed significantly(p<0.05).