• The Plant Pathology Journal
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• v.16 no.2
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• pp.70-78
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• 2000

No Abstract.See Full-text

• Molecules and Cells
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• v.25 no.3
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• pp.323-331
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• 2008

Plants are continually exposed to a variety of potentially pathogenic microbes, and the interactions between plants and pathogenic invaders determine the outcome, disease or disease resistance. To defend themselves, plants have developed a sophisticated immune system. Unlike animals, however, they do not have specialized immune cells and, thus all plant cells appear to have the innate ability to recognize pathogens and turn on an appropriate defense response. Using genetic, genomic and biochemical methods, tremendous advances have been made in understanding how plants recognize pathogens and mount effective defenses. The primary immune response is induced by microbe-associated molecular patterns (MAMPs). MAMP receptors recognize the presence of probable pathogens and evoke defense. In the co-evolution of plant-microbe interactions, pathogens gained the ability to make and deliver effector proteins to suppress MAMP-induced defense responses. In response to effector proteins, plants acquired R-proteins to directly or indirectly monitor the presence of effector proteins and activate an effective defense response. In this review we will describe and discuss the plant immune responses induced by two types of elicitors, PAMPs and effector proteins.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.258-263
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• 2004

Ripe fruit of pepper (Capsicum annuum) showed resistance to Colletotrichum gloeoporioides, but unripe fruit was susceptible. We previously isolated the PepTLP gene that induced in both unripe and ripe fruit by fungal infection and wound, and only in ripe fruit by jasmonic acid (JA) treatment. To examine further regulation of PepTLP, the action of specific agonist and antagonists of known signaling effector on the .PepTLP expression by fungal infection, wound, and JA was investigated. A similar dephosphorylation event negatively activated all the PepTLP expression in the ripe fruit by fungal infection, wound, and JA. The induction of PepTLP expression by wound is differentially regulated via phosphorylation and dephosphorylation step during pre- and post-ripening, respectively. In addition, the induction of PepTLP expression in the ripe fruit by wound and JA is differentially regulated via dephosphorylation and phosphorylation step, respectively. Only both wound and JA treatment has synergistic effect on the PepTLP expression in the unripe fruit. Both SA and JA treatments on the unripe fruit, and both wound or JA and SA on the ripe fruit could not do any effect on the expression of PepTLP. These results suggest that the induction of PepTLP expression is differentially regulated via complex regulatory system against fungal infection, wound, and JA treatment during pre- and post-ripening of pepper fruit.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.40-60
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• 2003

Fruit ripening represents a genetically synchronized system that involves developmental process unique to plant species, The phenomenon of ripening includes changes in color, texture, respiration rate, flavor, and aroma. Ripe fruits generally exhibit increased susceptibility to pathogen infection. However, fruits as a reproductive organ have their own protection mechanism against pathogens to maintain their integrity during seed maturation. In several nonclimacteric fruits, such as cherry, grape, and pepper, that do not have an ethylene burst during ripening, resistance against phytopathogens increases during ripening. Colletotrichum gloeosporioides is a causal agent of anthracnose disease in pepper plants (Capsicum annuum). We have established that C. gloeosporioides has susceptible and resistant interactions with pepper fruits during pre- and post-ripening stages, respectively. And we have interested in looking for a molecular mechanism that would explain the fungal resistance during ripening of nonclimacteric pepper fruit. In this presentation, a molecular characterization of the pepper esterase gene (PepEST) that is highly expressed in the resistant response will be demonstrated as an example of development and industrial applications of versatile-usable genes of plant.

• Journal of the Korea Safety Management & Science
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• v.19 no.4
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• pp.115-123
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• 2017

Recently there is a growing interest in the airborne spread of virus. In particular, there is growing interest in secondary infection through the air in the hospital. The distribution of air-born virus depends on ventilation system installed in a hospital. In this study, simulations were carried out to predict the move of air-born virus by ventilation system at hospital. Simulation results showed that pressure distribution was -372.05Pa ~ -3.45 Pa at 1st floor incase of only used mechanical exhaust at bathroom, shower stall, storage, kitchen etc.. if ventilation switch from used mechanical exhaust to mechanical exhaust & mechanical supply. Simulation results showed that pressure distribution was -336.44Pa at stair hall < -0.2Pa at bathroom < mean 1.19Pa at other room. So simulation results showed that using all of the mechanical supply and mechanical exhaust was more effective then the mechanical exhaust for maintain the pressure distribution in hospital. It was also showed that when using the mechanical supply and mechanical exhaust more effectively prevention of air born virus diffusion.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.67-73
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• 1996

This study was conducted to determine the effect of treatment with the plant-growth-promoting bacteria on the growth of red pepper(Capsicum annuum L.).The eight plant-growth-promoting bacteria were isolated from the humic soil in the forest region. The isolated bacteria(IB) was identified by the method of the biochemical test(API kit) and the composition of the fatty acid(MIDI system).The IBs were inoculated by spray of 17ml at 72 cell tray filled with peatmoss every week. respectively, with mixed liquid eulture of eight strains. The IBs were identified as Micrococcus sp.. Bacillus subtilis. Enterobacter agglomerans, Bacillus megaterium, Pseudomonas putida. Pseudomonas fluorescens, Xanthomonas maltophilia and Staphylococcus xylosus by API kit and MIDI system. The plant height number of leaves and leaf length of red pepper grown on peatmoss treated with the IB were better than those of nontreatment at the 10th day after inoculation.

• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.357-362
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• 1994

Chitinases and $\beta$-1,3-glucanases are believed to be important in defending plane against pathogens. Here, we investigated the expression of chitinase(s) in Arabidopsis thaliana cell suspension culture system in response to ethephon (2-chloroethyl phosphonic acid) which produces ethylene or a microbial elicitor, a bacterial pectin-degrading enzyme, $\beta$-1, 4-endopolygalactronic acid Iyase (PGA Iyase), treatment. Chitinase activity was measured either by radio chemical assay using $^3$H-labeled regenerated chitin as substrate or western blot analysis using antibody raised against tobacro chitinase(S). With 1 mg/mL of ethephon or 100 m units/mL of elicitor treatment, maximum levels of activity were reached after 48h. We also investigated distribution of chitinase activity in seedlings, leaves, and root of A. thaliana and found that root have the highest chitinase activity.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.20-28
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• 2009

The sustainability of conventional agriculture which is characterized by input dependent and ecologically simplified food production system is vague. Chemicals and present practices used in agriculture are not only costly but also have widespread implications on human and animal health, food quality and safety and environmental quality. Thus there is a need for alternative farming practices to sustain food production for the escalating population and conserve environment for future generations. The present research scenario in the area of plant microbe interactions for maintaining sustainable agriculture suggests that the level of internal regulation in agro-ecosystems is largely dependent on the level of plant and microbial diversity present in the soil. In agro-ecosystems, biodiversity performs a variety of ecological services beyond the production of food, including recycling of nutrients, regulation of microclimate and local hydrological processes, suppression of undesirable organisms and detoxification of noxious chemicals. Controlling the soil microflora to enhance the predominance of beneficial and effective microorganisms can help improve and maintain soil chemical and physical properties. The role of beneficial soil microorganisms in sustainable productivity has been well construed. Some plant bacteria referred to as plant growth-promoting rhizobacteria (PGPR) can contribute to improve plant growth, nutrient uptake and microbial diversity when inoculated to plants. Term PGPR was initially used to describe strains of naturally occurring non-symbiotic soil bacteria have the ability to colonize plant roots and stimulate plant growth PGPR activity has been reported in strains belonging to several other genera, such as Azotobacter, Azospirillum, Arthrobacter Bacillus, Burkhokderia, Methylobacterium, and Pseudomonas etc. PGPR stimulate plant growth directly either by synthesizing hormones such as indole acetic acid or by promoting nutrition, for example, by phosphate solubilization or more generally by accelerating mineralization processes. They can also stimulate growth indirectly, acting as biocontrol agents by protecting the plant against soil borne fungal pathogens or deleterious bacteria. Present review focuses on some recent developments to evolve strategies for better biotechnological exploitation of PGPR's.

• Molecules and Cells
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• v.44 no.11
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• pp.830-842
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• 2021

When perceiving microbe-associated molecular patterns (MAMPs) or plant-derived damage-associated molecular patterns (DAMPs), plants alter their root growth and development by displaying a reduction in the root length and the formation of root hairs and lateral roots. The exogenous application of a MAMP peptide, flg22, was shown to affect root growth by suppressing meristem activity. In addition to MAMPs, the DAMP peptide PEP1 suppresses root growth while also promoting root hair formation. However, the question of whether and how these elicitor peptides affect the development of the vascular system in the root has not been explored. The cellular receptors of PEP1, PEPR1 and PEPR2 are highly expressed in the root vascular system, while the receptors of flg22 (FLS2) and elf18 (EFR) are not. Consistent with the expression patterns of PEP1 receptors, we found that exogenously applied PEP1 has a strong impact on the division of stele cells, leading to a reduction of these cells. We also observed the alteration in the number and organization of cells that differentiate into xylem vessels. These PEP1-mediated developmental changes appear to be linked to the blockage of symplastic connections triggered by PEP1. PEP1 dramatically disrupts the symplastic movement of free green fluorescence protein (GFP) from phloem sieve elements to neighboring cells in the root meristem, leading to the deposition of a high level of callose between cells. Taken together, our first survey of PEP1-mediated vascular tissue development provides new insights into the PEP1 function as a regulator of cellular reprogramming in the Arabidopsis root vascular system.

• Journal of Animal Environmental Science
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• v.9 no.1
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• pp.45-56
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• 2003

$TAO^{TM}$ System is an auto-heated thermophilic aerated digestion process using a proprietary microbe called as a Phototropic Bacteria (PTB). High metabolic activity results in heat generation, which enables to produce a pathogen-free and digested liquid fertilizer at short retention times. TAO$^{TM}$ system has been developed to reduce a manure volume and convert into the liquid fertilizer using swine manure since 1992. About 100 units have been installed and operated in Korean swine farms so far. TAO$^{TM}$ system consists of a reactor vessel and ejector-type aeration pumps and foam removers. The swine slurry manure enters into vessel with PTB and is mixed and aerated. The process is operated at detention times from 2 to 4 days and temperature of 55 to $65^{\circ}C$. Foams are occurred and broken down by foam removers to evaporate water contents. Generally, at least 30% of water content is evaporated, 99% of volatile fatty acids caused an odor are removed and pathogen destruction is excellent with fecal coliform, rotavirus and salmonella below detection limits. The effluent from TAO$^{TM}$ system, called as the "TAO EFFLUX", is screened and has superb properties as a fertilizer. Normally N-P-K contents of screened TAO Efflux are 4.7 g/L, 0.375 g/L and 2.8 g/L respectively. The fertilizer effect of TAO EFFLUX compared to chemical fertilizer has been demonstrated and studied with various crops such as rice, potato, cabbage, pumpkin, green pepper, parsley, cucumber and apple. Generally it has better fertilizer effects and excellent soil fertility improvement effects. Moreover, the TAO EFFLUX is concentrated through membrane technology without fouling problems for a cost saving of long distance transportation and a commercialization (crop nutrient commodity) to a gardening market, for example.