• The Plant Pathology Journal
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• 제28권3호
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• pp.322-329
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• 2012

This study was conducted to investigate host and non-host disease resistances of kimchi cabbage plants to bacterial infection. Kimchi cabbage leaves responded differently to infections with a virulent strain of Xanthomonas campestris pv. campestris (Xcc) 8004 and two strains (85-10 and Bv5-4a.1) of non-host bacteria X. campestris pv. vesicatoria (Xcv). Non-host bacteria triggered a rapid tissue collapse of the leaves showing as brown coloration at the infected sites, highly increased ion leakage, lipid peroxidation and accumulation of UV-stimulated autofluorescence materials at the inoculated sites. During the observed interactions, bacterial proliferations within the leaf tissues were significantly different. Bacterial number of Xcc 8004 progressively increased within the inoculated leaf tissues over time, while growths of two non-host bacteria Xcv strains were distinctly limited. Expressions of pathogenesis-related genes, such as GST1, PR1, BGL2, VSP2, PR4 and LOX2, were differentially induced by host and non-host bacterial infections of X. campestris pathovars. These results indicated that rapid host cellular responses to the non-host bacterial infections may contribute to an array of defense reactions to the non-host bacterial invasion.

• Journal of Plant Biology
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• 제36권3호
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• pp.285-292
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• 1993

Cellular compatibility in the self-parasitism of Cuscuta australis R. Brown was studied at the ultrastructural level. The front cells of the haustorium penetrated the host stems independently grew within the host tissues and transformed into elongate, filamentous hyphae. Each hyphal cells contained a large nucleus and dense cytoplasm with abundant cell organelles. Multilamellar structures were contained in the cytoplasm and cell walls of the penetrating hyphal cells. When the hyphal cells did not yet invade the host cells, the middle lamella and the fused cellulosic cell walls of the two partners at the host-parasite interface were preserved well. As the invasion of the parasitic hyphal cells progressed, however, the middle lamella was not found at the interface and the host cell walls and plasma membranes were partially broken down. A hyphal cell penetrated deeply into the host cell had a more darkly stained cytoplasm with numerous of cell organelles. In the host cells attacked by the hyphal cells the limiting membranes of plastids were broken down and several vesicles were arrayed near the cell walls. No plasmodesmatal connections between the host and parasite cell walls were found; however, half-plasmodesmata were observed frequently on the side of the hyphal cell walls. These results suggested that the compatibility response in the self-parasitism of Cuscuta was expressed by cell walls, not by plasmodesmata, between the host and the parasite cells.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.9-9
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• 2018

Arctii Fructus (AF), which contains arctigenin (ARC) as a major constituent, is traditionally used as an anti-inflammatory medicine to treat inflammatory sore throat. Although several studies have proven its anti-inflammatory effects, there have been no reports on its use in inflammation related disorders such as obesity, cancer metastasis, and allergic responses. This study investigated the anti-obesity effect and anti-metastasis effect of AF and ARC. AF and ARC inhibited weight gain by reducing the mass of white adipose tissue in high fat diet (HFD)-induced obese mice. Serum cholesterol levels were also improved by AF and ARC. In in vitro experiments, AF and ARC decreased differentiation of white adipocytes. Furthermore, AF induced differentiation of brown adipocytes, which are able to consume surplus energy through non-shivering thermogenesis. Also, AF and ARC inhibited colon cancer and lung metastasis of colon cancer. They suppressed not only colorectal cancer cell progression by inhibiting cell growth, but also prohibited lung metastasis by regulating epithelial-mesenchymal transition (EMT), migration, and the invasion. These effects were confirmed in an experimental metastasis mouse model. In addition, AF and ARC inhibited mast cell mediated allergic responses. Collectively, our study suggests that AF and ARC might show inhibitory effects on inflammation related diseases, including obesity, cancer, cancer metastasis, and allergic responses.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.89.1-89
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• 2003

Disease suppression by ectomycorrhizal(ECM) fungi has been demonstrated on red pine seedlings. Culturing of pathogenic fungi on petri plates containing culture filtrates of ECM fungi showed that culture filtrates of the ECM fungus Hebeloma cylindrosporum may inhibit the mycelial growth of all tested soil-borne plant pathogenic(SBPP) fungi upto 60％, In order to examine the effects of ECM fungi on SBPP fungi and on red pine seedlings, both symbiotic and pathogenic fungi were inoculated into the soil with red pine seedlings by three inoculation methods; pre-inoculation of SBPP fungi 10 days before inoculation of ECM fungi, simultaneous inoculation of both fungi, post-inoculation of SBPP fungi 60 days after inoculation of ECM fungi. Seedling mortality, seedling growth, and ectomycorrhizal formation by the combined treatments were examined and compared. Pine seedlings were dead by the pre-inoculation of pathogenic fungi, except Rhizina undulate which required 9-12 days, within 6 days after inoculation. Among pathogenic fungi tested, Fusarium oxysporum was the most pathogenic with the mortality of 44％. However, no dead seedlings were shown by simultaneous inoculation of both fungi or pre-inoculation of ECM fungi. In addition, pine seedlings treated by simultaneous or post-inoculation of SBPP fungi were relatively higher than those treated by pre-inoculation in diameter at root crown and the number of ectomycorrhizal roots. There were no significant differences among inoculation methods in root length and dry weight of treated seedlings. It means that ECM fungi somehow play a role in protecting primary roots of red pine seedlings against invasion by the SBPP fungi.

• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.238-244
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• 2010

Rhizobia are well-known for their ability to infect and nodulate legume roots, forming a nitrogen-fixing symbiosis of agricultural importance. In addition, recent studies have shown that rhizobia can colonize roots and aerial plant tissues of rice as a model plant of the Graminaceae family. Here we show that rhizobia can invade tobacco, a model plant belonging to the Solanaceae family. Inoculation of seedling. roots with five GFP-tagged rhizobial species followed by microscopy and viable plating analyses indicated their colonization of the surface and interior of the whole vegetative plant. Blockage of ascending epiphytic migration by coating the hypocotyls with Vaseline showed that the endophytic rhizobia can exit the leaf interior through stomata and colonize the external phyllosphere habitat. These studies indicate rhizobia can colonize both below- and above-ground tissues of tobacco using a dynamic invasion process that involves both epiphytic and endophytic lifestyles.

• 한국환경과학회지
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• 제16권5호
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• pp.549-559
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• 2007

Vegetation surveys were performed at 45 plots along 10 highways cut slopes in South Korea. Total floral inventory, species richness and exotic plant percentage were obtained within each plot. Life history and life form of each species appeared were analyzed. Community types were classified using hierarchical cluster analysis and detrended correspondence analysis and non-metric multidimensional scaling were conducted from vegetation matrix. 292 species of vascular plants were discovered and the number of natives and exotics were 226 and 66, respectively. There were no significant differences of species richness and exotic plant percentage between cut slopes and rest areas. Hierarchical cluster analysis indicated five clear vegetation associations in cut slopes and rest areas. Detrended correspondence analysis indicated that species composition of total and native plants were similar along the highway cut slopes whereas exotic plants were distributed differentially along the highway cut slopes. in non-metric multidimensional scaling, the studied sites were more separated from each other on the basis of their species composition than the results of detrended correspondence analysis with respect to total, native and exotic plants. The both ordination represented that exotic plants have not been made uniform yet on cut slopes and rest areas by highway corridor in spite of diverse chronosequences after highway construction termination (1 to 22 years). This study showed that the distribution of species composition in exotic plants was different and localized on cut slopes and rest areas of highway in this representative peninsula area of North East Asia and the invasion of exotic plants can retard the process of plant species homogenization.

• 한국환경복원기술학회지
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• 제12권1호
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• pp.13-31
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• 2009

The objectives of this study were to offer the basic data for the restoration and conservation of forest wetland by surveying systematically the vascular plants of Sandeul wetland in Mt. Jaeyak, Miryang-si, Gyeongsangnam-do, Korea. The vascular plants in this wetland were recorded as 232 taxa; 74 families, 178 genera, 200 species, 27 varieties and 5 forma. The major communities were Quercus mongolica, Tripterygium regelii, Alnus japonica, Molinia japonica, Salix gracilistyla and Stephanandra incisa. The numbers of plant species by routes were 168 taxa in A-route, 126 taxa in B and 132 taxa in C. The ecological problems in Sandeul wetland were the afforestation of Pinus koraiensis and P. thunbergii, the appearance of naturalized plants, the invasion of species and the scour of valley. The Korean endemic plants were 5 taxa; Salix hallaisanensis, Hepatica insularia; Chrysosplenium barbatum, Ajuga spectabilis and Weigela subsessilis. The rare plants designated by Korea Forest Service were 3 taxa; Aristolochia manshuriensis, Chrysanthemum lineare and Iris ensata var, spontanea. The naturalized plants were 8 taxa; Rumex acetocella, R. crispus, Trifolium repens, Oenothera lamarckiana, Ambrosia artemisifolia var. elatior, Helianthus tuberosus, Erigeron annuus and Phleuum pratense.

• The Plant Pathology Journal
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• 제38권3호
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• pp.212-219
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• 2022

Fusarium root rot caused by the soil-borne fungus Fusarium solani is one of the most important fungal diseases of cassava in Thailand, resulting in high yield losses of more than 80%. This study aimed to investigate if the exogenous application of salicylic acid formulations (Zacha) can induce resistance in cassava against Fusarium root rot and observe the biochemical changes in induced cassava leaf tissues through synchrotron radiation based on Fourier-transform infrared (SR-FTIR) microspectroscopy. We demonstrated that the application of Zacha11 prototype formulations could induce resistance against Fusarium root rot in cassava. The in vitro experimental results showed that Zacha11 prototype formulations inhibited the growth of F. solani at approximately 34.83%. Furthermore, a significant reduction in the disease severity of Fusarium root rot disease at 60 days after challenge inoculation was observed in cassava plants treated with Zacha11 at a concentration of 500 ppm (9.0%). Population densities of F. solani were determined at 7 days after inoculation. Treatment of the Zacha11 at a concentration of 500 ppm resulted in reduced populations compared with the distilled water control and differences among treatment means at each assay date. Moreover, the SR-FTIR spectral changes of Zacha11-treated epidermal tissues of leaves had higher integral areas of lipids, lignins, and pectins (1,770-1,700/cm), amide I (1,700-1,600/cm), amide II (1,600-1,500/cm), hemicellulose, lignin (1,300-1,200/cm), and cellulose (1,155/cm). Therefore, alteration in defensive carbohydrates, lipids, and proteins contributed to generate barriers against Fusarium invasion in cassava roots, leading to lower the root rot disease severity.

• 환경생물
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• 제40권3호
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• pp.335-340
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• 2022

2017년 9월 부산 감만부두에서 국내 최초로 붉은불개미(Solenopsis invicta)가 검출된 이후, 농림축산검역본부에서는 외래개미류의 유입가능성이 높은 지역에 대해 주기적 예찰을 수행하고 있다. 그러나 현재 사용 중인 개미류 예찰용 트랩들은 개미가 들어갔다가 다시 쉽게 빠져나오거나, 토양이 없는 단단한 바닥 환경에서는 설치하기가 어려운 단점이 있다. 이를 해결하기 위해 다단협관을 이용하여 탈출이 어렵고, 콘크리트 같은 곳에서도 쉽게 설치가 가능한 신형 트랩을 개발하게 되었다. 신형 트랩은 함정트랩에 비해 4배 이상의 개미류 포획효과를 가지고 있으며, 포획된 개미들의 재탈출을 효과적으로 차단하는 것을 확인하였다. 새로 개발된 트랩을 통해 외래개미류의 국내 침입을 효과적으로 차단하기를 기대한다.

• Journal of Microbiology and Biotechnology
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• 제28권11호
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• pp.1896-1907
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• 2018

Salmonellosis is commonly associated with meat and poultry products, but an increasing number of Salmonella outbreaks have been attributed to contaminated vegetables and fruits. Enteric pathogens including Salmonella enterica spp. can colonize diverse produce and persist for a long time. Considering that fresh vegetables and fruits are usually consumed raw without heat treatments, Salmonella contamination may subsequently lead to serious human infections. In order to understand the underlying mechanism of Salmonella adaptation to produce, we investigated the transcriptomics of Salmonella in contact with green vegetables, namely cabbage and napa cabbage. Interestingly, Salmonella pathogenicity island (SPI)-1 genes, which are required for Salmonella invasion into host cells, were up-regulated upon contact with vegetables, suggesting that SPI-1 may be implicated in Salmonella colonization of plant tissues as well as animal tissues. Furthermore, Salmonella transcriptomic profiling revealed several genetic loci that showed significant changes in their expression in response to vegetables and were associated with bacterial adaptation to unfavorable niches, including STM14_0818 and STM14_0817 (speF/potE), STM14_0880 (nadA), STM14_1894 to STM14_1892 (fdnGHI), STM14_2006 (ogt), STM14_2269, and STM14_2513 to STM14_2523 (cbi operon). Here, we show that nadA was required for bacterial growth under nutrient-restricted conditions, while the other genes were required for bacterial invasion into host cells. The transcriptomes of Salmonella in contact with cabbage and napa cabbage provided insights into the comprehensive bacterial transcriptional response to produce and also suggested diverse virulence determinants relevant to Salmonella survival and adaptation.