• The Plant Pathology Journal
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• v.28 no.4
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• pp.364-372
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• 2012

Xanthomonas oryzae pv. oryzae causing bacterial leaf blight disease in rice produces and secretes Hpa1 protein that belongs to harpin protein family. Previously it was reported that Hpa1 induced defense responses when it was produced in tobacco. In this study, we expressed hpa1 gene in rice and Arabidopsis to examine the effects of Hpa1 expression on disease resistance to both fungal and bacterial pathogens. Expression of hpa1 gene in rice enhanced disease resistance to both X. oryzae pv. oryzae and Magnaporthe grisea. Interestingly, individual transgenic rice plants could be divided into four groups, depending on responses to both pathogens. hpa1 expression in Arabidopsis also enhanced disease resistance to both Botrytis cineria and Xanthomonas campestris pv. campestris. To examine genes that are up-regulated in the transgenic rice plants after inoculation with X. oryzae pv. oryzae, known defense-related genes were assessed, and also microarray analysis with the Rice 5 K DNA chip was performed. Interestingly, expression of OsACS1 gene, which was found as the gene that showed the highest induction, was induced earlier and stronger than that in the wild type plant. These results indicate that hpa1 expression in the diverse plant species, including monocot and dicot, can enhance disease resistance to both fungal and bacterial plant pathogens.

• Research in Plant Disease
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• v.6 no.1
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• pp.10-14
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• 2000

In 1998, bacterial shot hole of peach (Prunus persica) and Japanese plum(Prunus salicina) was found in Naju and Milyang. Five isolates of bacteria isolates from the diseased leaves and fruits of peach and Japanese plum were classified into genus Erwinia and Xanthomonas on diagnostic characteristics. Of five isolates, two were identified as X. campestris pv. pruni, three as E. nigrifluens. E.nigrifluens is the first description of bacteria which causes the disease on peach and Japanese plum in Korea. the symptoms caused by E. nigrifluens were hardly distinguished from those caused by X. campestris pv. pruni. In addition, it was observed that two pathogenic bacteria were isolated from most of naturally infected plants at the same time. from the reason mentioned above, we proposed to use a single common name \"bacterial shot hole of peach and Japanese plum\" for the both bacterial diseases, hereafter.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.10
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• pp.1823-1831
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• 2010

This paper proposes an automatic tracking control algorithm for efficiency improvement of photovoltaic generation. Increasing the power of PV systems should improve the efficiency of solar cells or the power condition system. The normal alignment of the PV module always have to run perpendicular to the sun's rays. The solar tracking system, able to improve the efficiency of the PV system, was initiated by applying that to the PV power plant. The tracking system of conventional PV power plant has been studied with regard to the tracking accuracy of the solar cells. Power generation efficiency were increased by aligning the cells for maximum exposure to the sun's rays. Using a perpendicular position facilitated optimum condition. However, there is a problem about the reliability of tracking systems unable to not track the sun correctly during environmental variations. Therefore, a novel control algorithm needs to improve the generation efficiency of the PV systems and reduce the loss of generation. This control algorithm is the proposed automatic tracking algorithm in this paper. Automatic tracking control is combined the sensor and program method for robust control in environment changing condition. This tracking system includes the insolation, rain sensor and anemometer for climate environment changing. Proposed algorithm in this paper, is compared to performance of conventional tracking control algorithm in variative insolation condition. And prove the validity of proposed algorithm through the experimental data.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.60-67
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• 2012

For the genetic differentiation of $Pseudomonas$ $syringae$ pathovar $tomato$, a total of 51 $P.$ $syringae$ pv. strains infecting 33 different host plants were analyzed using repetitive element PCR(REP-PCR) and universal rice primer PCR(URP-PCR). The entire DNA fingerprint profiles were analyzed using unweighted pair-group method with arithmetic averages (UPGMA). The 51 $P.$ $syringae$ pv. strains could be divided into five clusters based on 65% similarity by Rep-PCR using BOX, ERIC, and REP primers. $P.$ $syringae$ pv. $tomato$ cluster was well separated from other 31 $P.$ $syringae$ pathovars. $P.$ $syringae$ pv. $tomato$ cluster included only $P.$ $syringae$ pv. $maculicola$ and $P.$ $syringae$ pv. $tomato$. $P.$ $syringae$ pv. $tomato$ strains could be divided into two genetic groups. Meanwhile, the Pseudomonas pv. strains could be divided into four clusters based on 63% similarity by URP-PCR using 2F, 9F, and 17R primers. $P.$ $syringae$ pv. $tomato$ cluster was also well separated from 30 other $P.$ $syringae$ pathovars. In this case, $P.$ $syringae$ pv. $tomato$ cluster included $P.$ $syringae$ pv. $maculicola$, $P.$ $syringae$ pv. $berberidi$, and $P.$ $syringae$ pv. $tomato$. $P.$ $syringae$ pv. $tomato$ strains was also separated into two genetic groups by URP-PCR analysis. Overall, our work revealed that $P.$ $syringae$ pv. $tomato$ can be genetically differentiated from other $P.$ $syringae$ pathovars by the DNA fingerprint profiles of REP-PCR and URP-PCR. We first report that there are two genetically diverged groups in $P.$ $syringae$ pv. $tomato$ strains.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.41-45
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• 1999

Bacterial population densities on soybean pods from Chungnam province ranges 105~106 CFU/$\textrm{cm}^2$, whereas those of bacteria causing sprout rot ranged 0~103 CFU/$\textrm{cm}^2$. Erwinia chrysanthemi, Xanthomonas campestris pv. glycines, Staphylococcus sp., and Micrococcus sp. were identified as pathogenic bacteria causing soybean sprout rot. The population density of X. campestris pv. glycines was higher than those of other bacteria.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.61-65
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• 1995

Photosynthetic characteristics of soybean leaves infected with Pseudomonas syringae pv. glycinea were investigated for 8 days. The difference in photosynthesis rate between healthy and diseased soybean leaves decreased for 2 to 4 days after inoculation and then increased. In respiration rate, healthy and diseased leaves showed the same tendency as photosynthetic rate. The stomatal resistance increased following Pseudomonas syringae pv. glycinea infection. The total chlorophyll content of the infected leaf was less than that of the uninfected. Pseudomonas syringae pv. glycinea infection induced the malformation of stacked grana in chloroplast. Dry matter production declined after infection.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.125-128
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• 1997

Reactions of Pseudomonas syringae pv. actinidiae to 95 carbon sources in a 96-well microplate (BiOLOG GN MicroPlateTM) were investigated. The bacterium used 9 carbon sources such as D-mannitol, sucrose, etc., but did not use 62 carbon sources such as $\alpha$-cyclodextrin, dextrin, etc. Based on the reactions, a user data base for identification of P. syringae pv. actinidiae was constructed in Biolog program (BiOLOG MicroLogTM 2 system). P. syringae pv. actinidiae isolates collected from kiwifruits could be identified automatically with high similarity using the user data base, which could diagnose rapidly and easily whether the tree was infected with bacterial canker or not.

• Research in Plant Disease
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• v.18 no.4
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• pp.381-386
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• 2012

Nematode fauna in Dokdo island was investigated for two years between 2008 and 2009. Population density and biomass were $239,500m^2$ (26,000-836,000) and $103.9mg/m^2$ (3.0-388.6), respectively. Total of 31 species of nematodes were identified : Acrobeloides is the most important genus with prominence value (PV) of 117.8, followed by Rhabditidae (PV = 81.9), Prismatolaimus (PV = 39.0), and Aphelenchoides (PV = 31.4). Among feeding group, bacteriovorus nematode composed 77% of density and 62% of biomass followed by plant-parasitic and fungivorus nematodes. A species of Pratylenchus having distinctive tail terminus is under study as a new species. Biological indices, Shannon and Wiener index (2.46), Simpson's diversity index (0.86), Species evenness (0.73), Species richness (1.30) indicate that nematode fauna in Dokdo island is diverse and unique. This study may give a general idea of nematode fauna at the Dokdo island.

• The Plant Pathology Journal
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• v.15 no.1
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• pp.57-61
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• 1999

Xanthomonas campestris pv. glycines causes bacterial pustule disease on susceptible soybean leaves and produces a bacteriocin, named glycinecinA, against most xanthomonads including Xanthomonas campestris pv. vesicatoria. One of the 5 isolated DNA regions responsible for bacteriocin production, a 1.7 kb DNA region for the glycinecinA gene, was used as a probe to detect the presence of the homolog DNA in other bacterial strains. Among 55 bacterial strains tested, only X. campestris pv. glycines showed the positive signal with glycinecinA DNA. Two oligomers, heu2 and heu4, derived from a glycinecinA DNA were used to carry out the polymerase chain reaction (PCR) analysis with chromosomal DNA from 55 different bacterial strains including 24 different strains of X. campestris pv. glycines, 9 different pathovars of xanthomonads, and other 22 bacterial strains of different genus and species. By separation of the PCR products on agarose gel, a 0.86 kb DNA fragment was specifically detected when X. campestris pv. glycines was present in the amplification assay. The 0.86 kb fragment was not amplified when DNA from other bacteria was used for the assay. Southern analysis with glycinecinA DNA showed that the PCR signal was obtained with X. campestris pv. glycines isolates from various geographic regions and soybean cultivars. Therefore, the 1.7 kb DNA region for the glycinecinA gene can be used for the pathovar-specific probe for the DNA hybridization and the primers heu2 and heu4 can be used for the pathovar-specific primers for the PCR analysis to detect X. campestris pv. glycines.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.643-643
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• 2012

Increasing energy prices and growing concerns about global warming address the need to improve energy self-sufficiency in many industrial and municipal sectors. Wastewater treatment plants (WWTPs) are representative of energy-consuming facilities in Korea, accounting for 5% of national energy consumption. We present renewable energy technologies and energy self-sufficiency scenarios in a municipal WWTP ($30,000m^3d^{-1}$) located in Yongin, South Korea. By employing photovoltaics (PV, 135 kW), small hydropower turbine (10 kW), and thermal energy from treated effluent (25 RT: refrigeration ton) within the WWTP, a total of 142 tonne of oil equivalent (toe) of energy was estimated to be generated, accounting for $365ton\;CO_2\;yr^{-1}$ of greenhouse gas emission reduction. Core renewable technologies under consideration include 1) hybrid solar PV system consisting of fixed PV, dual-axis PV, and building integrated PV, 2) low-head small hydropower plant specifically designed for treated effluent, 3) effluent heat recovery system for heating and air conditioning. In addition to these core technologies, smart operation and management scheme will be presented for enhancing overall energy savings and distribution within the WWTP.