• Journal of Ginseng Research
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• v.15 no.1
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• pp.31-35
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• 1991

In order to know the optimum planting density under shading structures at different light intensity, We investigated the growth status, distribution of ginseng leaf area, correlation between planting density and root weight per plant and yield, correlation between leaf area index and root weight per plant and yield. According to the increase of planting density the leaf area per plant was decreased, but leaf area index (L.A.I) was increased. Ginseng leaf population at different lines under common straw shading were distributed mainly in frost lines but polyethylene net shading at 10fo light intensity were distributed equally in all lines. Optimum planting density in common straw shading at 5% light intensity was 55 plant per tan (90 cmX180 cm) and polyethylene net shading 81 10% light intensity was 60 plant per tan, in consideration of root weight and yield. Optimum leaf area index was 2.4 under common straw shading at 5% light intensity but was 2.7 under polyethylene net shading at 10% light intensity.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4408-4425
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• 2023

Alarm flood due to abnormality propagation is the most difficult alarm overloading problem in nuclear power plants (NPPs). Root-cause analysis is suggested to help operators in understand emergency events and plant status. Multilevel Flow Modeling (MFM) has been extensively applied in alarm management by virtue of the capability of explaining causal dependencies among alarms. However, there has never been a technique that can identify the actual root cause for complex alarm situations. This paper presents an automated root-cause analysis system based on MFM. The causal reasoning algorithm is first applied to identify several possible root causes that can lead to massive alarms. A novel root-cause ranking algorithm can subsequently be used to isolate the most likely faults from the other root-cause candidates. The proposed method is validated on a pressurized water reactor (PWR) simulator at HAMMLAB. The results show that the actual root cause is accurately identified for every tested operating scenario. The automation of root-cause identification and ranking affords the opportunity of real-time alarm analysis. It is believed that the study can further improve the situation awareness of operators in the alarm flooding situation.

• Journal of Ginseng Research
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• v.15 no.1
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• pp.21-30
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• 1991

This study was conducted to know the elects of light intensity of polyethylene net shading on the growth status, photosynthesis and root yield of ginseng plants. Polyethylene net shading of loft transmittance was the best one among light intensities of polyethylene net used in view of photosynthesis and decreasing of early leaf defoliation. According to increase of light intensity under the shading chlorophyll contents of ginseng leaves were decreased. As it was increased over 2 mg/g Photosynthesis and total saponin of leaves showed on the decrease remarkably. The rate of alternaria blight of ginseng plants showed the positive correlation between light intensity and leaking rate. The shading of 10% transmittance in root yield was increased by 40% in 6-year-old ginseng plant as compared with common straw shading, due to decreased missing plant and increased root weight.

• Research in Plant Disease
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• v.27 no.3
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• pp.91-98
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• 2021

The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

• Korean Journal of Plant Resources
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• v.13 no.2
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• pp.131-139
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• 2000

The effects of the simulated acid rain on the growth response and water status of Glycine soja was observed in 2 months-old seedlings. The seedlings were treated with acid rain(pH 3.5), three times per week. Glycine soja showed significant reduction in the total length, total weight, dry weight, water contents and top/root ratio after treatment of simulated acid rain(pH 3.5) for 56 days. The growth of shoot was more susceptible to acid rain than that of roots. On the contray, Number of lateral roots, water saturation deficit and epidermis transpiration was higher than that of control(pH 5.6) after 56 days treatment of simulated acid rain.

• Journal of Plant Biology
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• v.37 no.3
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• pp.343-347
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• 1994

In order to compare the adjustment of 6 oak species to water stress, the components of water status, tissue elastic modulus, free proline content of leaves and morphological characteristics were determined in pot culture. uercus dentata and . mongolica responded effectively to drought with high root : shoot (R/S) ratio or maintenance of high turgor pressure by large and fast osmotic adjustment and . variabilis with maintenance of high turgor pressure by low elastic modulus under drought. Meanwhile, . aliena and . serrata responded effectively with low omotic potential (Ψo) at full saturation and . acutissima with long root in spite of rigid cell wall and high osmotic potential (Ψo) at full saturation. Proline content in leaves of . dentata, . mongolica and . aliena increased early and rapidly at high leaf water potential (Ψleaf). The results indicate that 6 oak species have adjustment different from each other to water stress.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.614-618
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• 2017

The root-knot nematode Meloidogyne incognita infects a variety of plants, including Arabidopsis thaliana. During migration, root-knot nematodes secrete different proteins to modify cell walls, which include pectolytic enzymes. However, the contribution of host cell wall proteins has not been described during this process. The function of two DUF642 cell wall proteins, BIIDXI (BDX, At4g32460) and TEEBE (TEB, At2g41800), in plant development could be related to the regulation of pectin methyl esterification status in the cell walls of different tissues. Accordingly, the expression of these two genes is up-regulated by auxin. BDX and TEB were highly induced during early M. incognita inoculation. Moreover, cell wall localization of the proteins was also induced. The cell wall localization of BDX and TEB DUF642 proteins during M. incognita early inoculation suggested that these two proteins could be involved in the regulation of the degree of pectin methylation during cell separation.

• Proceedings of the Botanical Society of Korea Conference
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• 1995.06a
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• pp.40-56
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• 1995

During the past two decades, China has seen her great progress in plant biotechnology. Since the Chinese market of herb medicine is huge, while the plant resources are shrinking, particular emphasis has been placed in plant tissue and cell cultures of medicinal plants, this includes fast propagation, protoplast isolation and regeneration, cell suspension cultures and large scale fermentation. To optimize culture conditions for producing secondary compounds in vitro, various media, additives and elicitors have been tested. Successful examples of large scale culture for the secondary metabolite biosynthesis are quite limited : Lithospermum ery throrhizon and Arnebia euchroma for shikonin derivatives, Panax ginseng, P. notoginseng, P. quinquefolium for saponins, and a few other medicinal plants. Recent development of genetic transformation systems of plant cells offered a new approach to in vitro production of secondary compounds. Hairy root induction and cultures, by using Ri-plasmid, have been reported from a number of medicinal plant species, such as Artemisia annua that produces little artemisinin in normal cultured cells, and from Glycyrrhiza uralensis. In the coming five years, Chinese scientists will continue their work on large scale cell cultures of a few of selected plant species, including Taxus spp. and A. annua, for the production of secondary metabolites with medicinal interests, one or two groups of scientists will be engaged in molecular cloning of the key enzymes in plant secondary metabolism.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.27-27
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• 2015

Clubroot (Plasmodiophora brassicae) is a serious agricultural problem affecting Brassica crop production worldwide. It also infects the model plant Arabidopsis thaliana. During infection, this biotrophic pathogen manipulates the development and metabolism of its host leading to the development of galls in the root and hypocotyl. In turn, its own development is strongly influenced by the host. The aim of this study is to investigate the metabolism of clubroot-infected plants using a combination of transcriptomic and metabolomic approaches. We have used direct injection mass spectrometry to obtain a metabolic fingerprint of when changes in the metabolome occur and linked this with changes in host and pathogen gene expression. We have identified alterations in carbohydrate metabolism that occur during P. brassicae infection of A. thaliana plants. Transcriptomic analysis showed that host genes associated with sugar transport and metabolism were induced during gall formation and that the pathogen also expresses genes associated with these processes. We have examined the impact of inactivating host sucrose synthase, cytosolic invertase and sugar permeases on gall formation, identifying host genes that are required for gall formation. We have also explored how sugar status is changed in root tissue, developing and mature leaf during infection of wild type and mutant plants.

• Korean Journal of Plant Resources
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• v.25 no.3
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• pp.323-328
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• 2012

This paper describes the potential use of deep sea water to stimulate seed germination in both common and Tartary buckwheat. Treatment of 10% deep sea water at $25^{\circ}C$ would slightly enhance germination of buckwheat seeds compared to non-DSW treatment and other temperature. In this study, the significant effects of photoperiod and temperature on seedling growth were also found in the HL treatment for the number of leaf, plant height, and plant fresh weight and LL treatment for root length and leaf size. Common buckwheat (Suwon No.1) showed higher rate (93%) of flowering plants in the HS and LL (93% of flowering rates) than those revealed in the HS and LS treatment, while the low percentage(67%) of plant flowering plants was shown in the LS treatment. All plants (100%) of a Korean landrace, Ahndong-jaerae showed flowers in the HS and LS treatment. HL and LL treatment status did not occur in the plant's flowering. Any Tartary buckwheat (KW45) plant did not yet flowered when it was 21 days-old.