• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.198-202
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• 2013

To produce transgenic cucumber expressing Nit gene coffering abiotic resistance, the cotyledonary-node explants of cucumber (cv. Eunsung) were inoculated with A. tumefaciens transformed with pPZP211 or pCAMBIA2300 carrying Nit gene, that has cis-acting element involved in resistance to various abiotic environmental stresses. After co-cultivation, the procedures of selection, shoot initiation, shoot elongation, and plant regeneration were followed by cotyledonary-node transformation method (CTM, Jang et al. 2011). The putative transgenic plants were selected when shoots were grown to a length greater than 3 cm from the cotyledonary-node explants on selection medium supplemented with 100 mg/L paromomycin as a selectable agent. The confirmation of transgenic cucumber was based on the genomic PCR, Southern blot analysis, RT-PCR, and Northern blot analysis. A 105 shoots (4.12%) selected from the selection mediums were obtained from 2,547 explants inoculated. Of them, putative transgenic plants were only confirmed with 45 plants (1.77%) by genomic PCR analysis. Transgenic plants showed that the Nit genes integrated into each genome of 39 plants (1.53%) by Southern blot analysis, and the expression of gene integrated into cucumber genome was only confirmed at 6 plants (0.24%) by RT-PCR and Northern blot analysis. These results lead us to speculate that the genes were successfully integrated and expressed in each genome of transgenic cucumber.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.51-56
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• 2008

Azuki bean has never been commercially grown in Thailand, due in part to a lack of suitable varieties. A core collection of 114 azuki bean accessions, originally from different parts of China(northern, central, southern) representing the germplasm of Chinese land races, were evaluated in the experimental field of the Institute of Vegetable Crops, Jiangsu Academy of Agricultural Sciences, China from June to October 2004. The same experiment was repeated at Kamphaeng Saen campus of Kasetsart University, Thailand from February to May 2005. Yield, yield components, and agronomic traits were recorded in all accessions in order to identify certain genotypes for further investigation. The statistical parameters that were used as indicators of phenotypic variation were mean, coefficient of variability(CV), correlation coefficient(r), range, mean difference, and phenotypic clustering of the accessions. The results indicated that the azuki bean varieties planted in Kamphaeng Saen were shorter, earlier in growing duration, and lower in plant height, seed yield per plant, 100-seed weight, and pods per plant as compared to when they were grown in China. This discrepancy was caused largely by the combined effect of temperature, rainfall, and day length. The traits that were rather stable in both locations were branches per plant and seeds per pod. Azuki bean varieties from northern China showed higher response to the changing environments compared with those from central and southern China. Some agronomic traits showed high correlation coefficient between the environments in Thailand and China. The CV of agronomic traits in both locations were ranked in descending order as follows: seed yield per plant, pods per plant, branches per plant, plant height, 100-seed weight, seeds per pod, and growing duration. The CV of seeds per pod and branches per plant were almost the same in both locations. Yield per plant in China correlated well(r=0.75) with pods per plant, but not with the other traits. Based on their response to both environments, the azuki bean accessions can be broadly divided into four groups, viz. northern 1, northern 2, central, and southern. This implied that there was more diversity, but probably less stability among the accessions originating from northern China.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.798-802
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• 2005

Crude extracts of thirty seaweeds collected in Korea were obtained using 50% ethanol, and total phenolic contents and antioxidant activities were compared. Two brown algae, Ecklonia cava (E. cava) and Sargassum siliquastrum (S. siliquastrum), showing high antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and superoxide anion radical scavenging activity were further investigated for their inhibitory effects on tyrosinase activity. The E. cava extract had the highest total phenolic content among the seaweeds extracts. Total phenolic contents were strongly correlated with antioxidant activity in the thirty seaweed extracts ($R^2\;=\;0.9169$). The E. cava and S. siliquastrum extracts exhibited higher inhibition to tyrosinase activity than butylated hydroxytoluene (BHT) and epigallocatechin gallate (EGCG).

• Korean Journal of Medicinal Crop Science
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• v.22 no.5
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• pp.384-390
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• 2014

This study was carried out in order to investigate the early growth and root development characteristics of Peucedanum japonicum container seedlings. The experiment was performed by containers (128 and 200 cavities containers) and shading levels (0%, 35%, 50% and 75% shading). Germination rate of P. japonicum seeds was getting higher in the lower shading level and the highest in the full sunlight (71.9%). Plant height was the highest under 50% shading of all containers. Fresh weight and dry weight of the shoot (leaves + stem) were the highest under 50% shading of all containers, too. Meanwhile, fresh weight and dry weight of the root per plant were the highest under the full sunlight of 128 cavities container such as 0.34 g and 0.03 g, respectively. Total root length, root project area and root surface area were higher under the full sunlight of 128 cavities container such as 234.5 cm, $6.6cm^2$ and $20.8cm^2$, respectively and the next higher was under 35% shading such as 201.7 cm, $5.9cm^2$ and $18.4cm^2$, respectively. A case of root volume was the highest with $0.15cm^3$ under the full sunlight. As a result of the surveying the whole experiment, it is concluded that the shoot and root of P. japonicum seedling grow nicely by maintaining 35% shading.

• Journal of Plant Biology
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• v.32 no.4
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• pp.351-362
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• 1989

Four species of marine algae, 3 red and 1 brown algae, were newly found from southern coast of Korea including Cheju Island in the course of floristic study. amphiroa itonoi Srimanobhas et Masaki and Hypnea variabilis Okamura were collected from intertidal zone and the others, Aglaothamnion oosumiense Itono and Sphacelaria caespitosa Takamatsu were from subtidal zone.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.38.2-38
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• 1999

• Journal of Plant Biology
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• v.28 no.4
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• pp.297-304
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• 1985

Two Korean species of Centroceras K tzing, Ceramiaceae was investigated taxonomically. C. clavulatum (Ag.) Montagne collected at several sited along the coast of Korea was characterized by regular dischotomous branches with whorl spines at every node, whereas, C. distichum Okamura collected at Soando in the southern coast was by alternate branches with gland cells around nodes. Biogeographic data show that Korea is almost northern limit in distribution of the former species.

• Journal of Plant Biology
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• v.17 no.2
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• pp.84-86
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• 1974

This paper is proposed to describe a new species and two formae offlowering plants from central and southern Korea. The taxa of new plants are as follows: Miscanthus chejuensis Y. Lee, sp. nov. Rhododendron schlippenbachii Maxim. form. albiflorum Y. Lee, form. nov. Scilla scilloides (Lindl.) Druce form. albida Y. Lee, form. nov.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.2
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• pp.104-112
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• 2016

A double-cropping system with soybean (Glycine max) following the cultivation of potato, garlic, and onion is widely adopted in the southern region of Korea. For this system, marginal dates for planting must be determined for profitable soybean yields, because the decision to plant soybean as a second crop is occasionally delayed by harvest of the first crop and weather conditions. In order to investigate the effect of planting date on soybean yield, three cultivars (early and late maturity) were planted on seven different dates from May 1 to July 30 in both paddy and upland fields across 2012 and 2013. Soybean yields were significantly different among the planting dates and the cultivars; however, the interaction between cultivar and planting date was not significant. Based on linear regression, the maximum yield of soybean was reached with a June 10 planting date, with a sharp decline in yield for crops planted after this date. The results of this study were consistent with those of a previous one that recommends early and mid-June as the optimum planting period. Regardless of soybean ecotype, a reduction in yield of greater than 20% occurred when soybean was planted after mid-July. Frost during soybean growth can reduce yields, and the late maturity cultivars planted on July 30 were damaged by frost before completing maturation and harvest; however, early maturity cultivars were safely harvested. For sufficient time to develop and reach profitable yields, the planting of soybean before mid-July is recommended.

• Journal of Ecology and Environment
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• v.43 no.4
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• pp.352-363
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• 2019

Background: Invasive plant species are considered a major threat to biodiversity, ecosystem functioning, and human wellbeing worldwide. Climatically suitable ranges for invasive plant species are expected to expand due to future climate change. The identification of current invasions and potential range expansion of invasive plant species is required to plan for the management of these species. Here, we predicted climatically suitable habitats for 11 invasive plant species and calculated the potential species richness and their range expansions in different provinces of the Republic of Korea (ROK) under current and future climate change scenarios (RCP 4.5 and RCP 8.5) using the maximum entropy (MaxEnt) modeling approach. Results: Based on the model predictions, areas of climatically suitable habitats for 90.9% of the invasive plant species are expected to retain current ecological niches and expand to include additional climatically suitable areas under future climate change scenarios. Species richness is predicted to be relatively high in the provinces of the western and southern regions (e.g., Jeollanam, Jeollabuk, and Chungcheongnam) under current climatic conditions. However, under future climates, richness in the provinces of the northern, eastern, and southeastern regions (e.g., Seoul, Incheon, Gyeonggi, Gyeongsangnam, Degue, Busan, and Ulsan) is estimated to increase up to 292%, 390.75%, and 468.06% by 2030, 2050, and 2080, respectively, compared with the current richness. Conclusions: Our study revealed that the rates of introduction and dispersion of invasive plant species from the western and southern coasts are relatively high and are expanding across the ROK through different modes of dispersion. The negative impacts on biodiversity, ecosystem dynamics, and economy caused by invasive plant species will be high if preventive and eradication measures are not employed immediately. Thus, this study will be helpful to policymakers for the management of invasive plant species and the conservation of biodiversity.