• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.75.2-76
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• 2002

• The Plant Pathology Journal
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• 제29권1호
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• pp.110-115
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• 2013

Theobroxide, a novel compound isolated from a fungus Lasiodiplodia theobromae, stimulates potato tuber formation and induces flowering of morning glory by initiating the jasmonic acid synthesis pathway. To elucidate the effect of theobroxide on pathogen resistance in plants, Nicotiana benthamiana plants treated with theobroxide were immediately infiltrated with Pseudomonas syringae pv. tabaci. Exogenous application of theobroxide inhibited development of lesion symptoms, and growth of the bacterial cells was significantly retarded. Semiquantitative RT-PCRs using the primers of 18 defense-related genes were performed to investigate the molecular mechanisms of resistance. Among the genes, the theobroxide treatment increased the expression of patho-genesis-related protein 1a (PR1a), pathogenesis-related protein 1b (PR1b), glutathione S-transferase (GST), allen oxide cyclase (AOC), and lipoxyganase (LOX). All these data strongly indicate that theobroxide treatment inhibits disease development by faster induction of defense responses, which can be possible by the induction of defense-related genes including PR1a, PR1b, and GST triggered by the elevated jasmonic acid.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2004년도 The 2004 KSPP Annual Meeting & International Symposium
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• pp.65-67
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• 2004

During initial interactions of bacteria with their host plants, most plants recognize the bacterial infections and repel the pathogen by plant defense mechanism. The most active plant defense mechanism is the hypersensitive response (HR) which is the localized induced cell death in the plant at the site of infection by a pathogen. A primary locus induced in gram-negative phytopathogenic bacteria during this initial interaction is the Hrp locus. The Hrp locus is composed of a cluster of genes that encodes the bacteral Type 111 machinery that is involved in the secretion and translocation of effector proteins to the plant cell. DNA sequence analysis of hrp gene in phytopathogenic bacteria has revealed a Hrp pathogenicity is]and (PAI) with a tripartite mosaic structure. For many gram-negative pathogenic bacteria, colonization of the host's tissue depends on the type III protein secretion system (TTSS) which secrets and translocates effector proteins into the host cell. Effectors can be divided into several groups including broad host range effectors, host specific effectors, disease specific effectors, and effectors inhibit host defenses. The role of effectors carrying LRR domain in plant resistance is very elusive since most known plant resistance gene carry LRR domain. Host specific effectors such as several avr gene products are involved in the determination of the host specificity. Almost all the phytopathogenic Xanthomonas spp. carry avrBs1, avrBs2, and avrBs3 homologs. Some strains of X. oryzae pv. oryzae carry more than 10 copies of avrBs3 homologs. However, the functions of all those avr genes in host specificity are not characterized well.;

• Journal of Plant Biotechnology
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• 제41권1호
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• pp.1-9
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• 2014

So far it has been generally considered that proteomic approaches are very useful for studying plant-microbes interaction. In this review, recent studies based on papers published from 2010 to 2013 have investigated proteomics analysis in various interaction during plant-fungal pathogen infection by means of gel-based proteomics coupled with mass spectrometry (MS)-based analysis. In rice, three papers focused on rice-Magnaporthe oryzae interaction were mainly reviewed in this study. Interestingly, another study showed proteomic changes in rice inoculated with Puccinia triticina, which is not only an fungal pathogen in wheat and but also results to the disease resistance with non-host defense manner in rice. Additionally, proteomics analysis has been widely subjected to understand defense mechanism during other crops (wheat, tomato, strawberry and mint) and their fungal pathogen interaction. Crops inoculated are analyzed to identify differentially regulated proteins at various tissues such as leaf and apoplast using 2-DE analysis coupled with various MS approaches such as MALDI-TOF MS, nESI-LC-MS/MS and MudPIT, respectively. Taken together, this review article shows that proteomics is applicable to various organisms to understand plant-fungal pathogen interaction and will contribute to provide important information for crop disease diagnosis and crop protection.

• Journal of Plant Biotechnology
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• 제44권1호
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• pp.1-11
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• 2017

Evolutionary studies conducted on NAC (NAM, ATAF1&2, and CUC2) genes for all major groups of land plants, indicate the presence of the NAC subfamilies, even in the early land plants. The varied roles played by NAC proteins in plant growth and development range from the formation of shoot apical meristem, floral organ development, reproduction, lateral shoot development, and defense responses to biotic and abiotic stresses. Considering the value and importance of solanaceous crops, the study of NAC proteins in these plants needs to be intensified. This will help to identify and functionally characterize their promoters, which will subsequently aid in engineering plants with improved performance under stressful conditions. In this review, the functionally characterized NAC transcription factors specific to tomato, potato, tobacco, chili pepper and eggplant (aubergine) are summarized, clearly indicating their biological functions in the defense mechanism of the plants, against biotic and abiotic stresses.

• The Plant Pathology Journal
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• 제25권4호
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• pp.381-388
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• 2009

On screening pathogen-resistant soybean, we identified a WRKY type transcription factor named a Glycine max WRKY1 (GmWRKY1). Expression of GmWRKY1 gene was induced in the soybean sprout by Pseudomonas infection. The GmWRKY1 was expressed in all of the tissues with high levels in stems, leaves and developing seeds. The protein Gm WRKY1 contains highly conserved two WRKY DNA-binding domains having two $C_2-H_2$ zinc-finger motif ($C-X_{4-5}-C-X_{22-23}-H-X-H$) in its N-terminal and C-terminal amino acid sequences. In electrophoresis mobility shift assay, the GmWRKY1 protein bound specifically to W-box elements in the promoters of defense related genes. These results demonstrated that GmWRKY1 is one of the soybean WRKY family genes and the plant-specific transcription factors for defense processes.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.236-236
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• 2017

Low soil pH causes from $H^+$ rhizotoxicity results in nutrients unavailability in the growing media, inhibits plant growth, development and reduces crop yields. The present study was carried out to reveal morpholophysiological and biochemical responses of wheat (Triticum aestivum L.) to acidity stress. Four wheat varieties viz. BARI Wheat-21, BARI Wheat-25, BARI Wheat-26 and BARI Wheat-30 were used in the study. Eight-day-old seedlings were exposed to different pH levels (3.5, 4.5, 5.5 and 6.5) of growing media. Acidity stress at any level reduced biomass, water, and chlorophyll contents in all the varieties; whereas BARI Wheat-26 showed the least damage. $H^+$ rhizotoxicity also caused oxidative stress through excess production of reactive oxygen species and methylglyoxal which increase lipid peroxidation in all the varieties but the lowest oxidative damage was observed in BARI Wheat-26 due to better performance of the antioxidant defense and glyoxalase systems. Considering the growth, physiological and biochemical attributes BARI Wheat-26 may be considered as acidity stress tolerant, among the variety examined.

• The Plant Pathology Journal
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• 제26권2호
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• pp.110-114
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• 2010

WRKY transcription factors are known to be involved in many different biological processes including plant response to biotic stress, abiotic stress, and plant development. WRKY proteins are extensively studied in Arabidopsis. Recently, reports on WRKY proteins are rapidly increasing in the other plant species, especially in rice. Therefore, this review will discuss the function of rice WRKY proteins reported so far.

• Mycobiology
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• 제29권1호
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• pp.48-53
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• 2001

Plants have the ability to acquire an enhanced level of resistance to pathogen attack after being exposed to specific biotic stimuli. To obtain plant growth-promoting rhizobacteria inducing resistance against cucumber anthracnose by Colletotrichum orbiculare, more than 800 strains of rhizobacteria were screened in the greenhouse. Among these strains, Bacillus amyloliquefaciens solate EXTN-1 showed significant disease control efficacy on the plants. Induction of pathogenesis-related(PR-la) gene expression by EXTN-1 was assessed using tobacco plants transformed with PR-1a::$\beta$-glucuronidase(GUS) construct. GUS activities of tobacco treated with EXTN-1 and salicylic acid-treated transgenic tobacco were significantly higher than those of tobacco plants with other treatments. Gene expression analyses indicated that EXTN-1 induces the accumulation of defense-related genes of tobacco. The results showed that some defense genes are expressed by the treatment with EXTN-1 suggesting the similar resistance mechanism by salicylic acid.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.944-945
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• 2006

A new tungsten heavy alloy with hybrid structure was manufactured for the kinetic energy penetrator. The tungsten heavy alloy is composed of two parts: core region is molybdenum added heavy alloy to promote the self-sharpening; outer part encompassing the core is conventional heavy alloy to sustain severe load in a muzzle during firing. From ballistic test, it was found that the penetration performance of the hybrid structure tungsten heavy alloy is higher than that of conventional heavy alloy. This heavy alloy is thought to be very useful for the penetrator in the near future.