• Molecules and Cells
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• 제19권3호
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• pp.418-427
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• 2005

When inoculated into sensitive tobacco Xanthi-nn plants, the crucifer and garlic-infecting Tobacco mosaic virus (TMV-Cg) induces local necrotic lesions that resemble those seen in the hypersensitive response (HR) of resistant tobacco plants. However, unlike these, tobacco Xanthi-nn plants do not become resistant to infection and the virus spreads systemically causing a severe disease characterized by necrotic lesions throughout the plant. To identify the viral protein that elicits this necrotic response, we used a set of hybrid viruses constructed by combination of TMV-Cg and the tobacco mosaic virus strain U1 (TMV-U1). In this study we present evidence that the coat protein of TMV-Cg (CPCg) is the elicitor of the necrotic response in tobacco Xanthi-nn plants. Local and systemic necrotic lesions induced by TMV-Cg and by the hybrid U1-CPCg -that carries CPCg in a TMV-U1 context- are characterized by cell death and by the presence of autoflorescent phenolic compounds and $H_2O_2$, just like the HR lesions. In addition, defense-related genes and detoxifying genes are induced in tobacco Xanthi-nn plants after TMV-Cg and U1-CPCg inoculation. We postulate that in our system, CPCg is recognized by sensitive tobacco plants that mount an incomplete defense response. We call this an HR-like since it is not enough to induce plant resistance.

• 한국연초학회지
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• 제16권1호
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• pp.57-64
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• 1994

Burley tobacco (Nicotiana tabacum L.) KB 108 was developed from a single cross between KB 104 and TC 591 which was developed from a cross between Burley 49 and Tobacco Introduction 1406. It was tested for its resistance to black shank, potato virus Y(PVY), TMV and agronomic characteristics under field conditions. KB 108 has resistance to tobacco mosaic virus(TMV) and necrotic strain of potato virus Y(PVY-VN) with secreting glandular trichomes. It has also moderate resistance to black shank caused by phytophthora parasitica val. Nicotianae. KB 108 has an up-right plant growth habit similar to Burley 21. It flowers about 1-2 days later than Burley 21. The leaf width and length of KB 108 are approximately 3 cm wider and longer than those of Burley 21. The yield of KB 108 was higher 4%, nearly equal in value per kg compared to Burley 21.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1995년도 제9회 식물생명공학 심포지움 식물육종과 분자생물학의 만남 The 9th Plant Biotechnology Symposium -Breeding and Molecular Biology-
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• pp.131-132
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• 1995

• 한국연초학회지
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• 제18권1호
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• pp.21-29
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• 1996

Tobacco plants resistant (cvs. Xanthi-nc and Samsun-NN) and susceptible (cv. NC 82) to tobacco mosaic virus (TMV) were inoculated with TW to obtain basic information about the characteristics of resistance expression in tobacco plants by examining the viral populations, symptom development and gene expression of pathogenesis-related proteins (PR-proteins) such as PR-1 and $\beta$-1, 3-glucanase in different temperature conditions. TMV populations in resistant plants increased more at 37$^{\circ}C$ than at 27$^{\circ}C$, while the viral populations increased continuously and were not significantly influenced by the temperature conditions in the susceptible tobacco plants. Infection sites of resistant tobacco leaves were remarkably expanded in proportion with increased time at the high temperature.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1250-1258
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• 2009

Bacillus spp., as a type of plant growth-promoting rhizobacteria (PGPR), were studied with regards promoting plant growth and inducing plant systemic resistance. The results of greenhouse experiments with tobacco plants demonstrated that treatment with the Bacillus spp. significantly enhanced the plant height and fresh weight, while clearly lowering the disease severity rating of the tobacco mosaic virus (TMV) at 28 days post-inoculation (dpi). The TMV accumulation in the young non-inoculated leaves was remarkably lower for all the plants treated with the Bacillus spp. An RT-PCR analysis of the signaling regulatory genes Coil and NPR1, and defense genes PR-1a and PR-1b, in the tobacco treated with the Bacillus spp. revealed an association with enhancing the systemic resistance of tobacco to TMV. A further analysis of two expansin genes that regulate plant cell growth, NtEXP2 and NtEXP6, also verified a concomitant growth promotion in the roots and leaves of the tobacco responding to the Bacillus spp.

• 한국연초학회지
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• 제19권2호
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• pp.83-91
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• 1997

The vein-necrosis strain or potato virus Y (PVY-Vff) and black shank (Phytophlhora parasitica roar. nicotianae) causes severe damage on burley tobacco(Wicotiana tabacum L.) in Korea, A new burley tobacco resistance to PVY and black shank, KB 110, was developed by Korea Ginseng and Tobacco Research Institute. It was developed from the cross of Burley 21 with TC 591 in 1990, and was backrossed to Burley 21 in the following season. TC 591 has resistance to PVY and moderate resistance to race 0 of black shank, but it is susceptible to tobacco mosaic vim (TMV). KB 110 was evaluated for its resistance to PVY, TMV and black shank in the greenhouse and at fields for preliminary and performance trials. KB 110 which has secreting glandular trichomes was resistant to PVY-VN, TW and black shank. It had an erect growth habit and two more leaves per plant than that of Burley 21, and matures two to three days later. It yielded approximately 3 percent more cured leaf than the standard cultivar Burley 21, but other plant characteristics were very similar to those of Burley 21. It had acceptable standards for chemical and physical characteristics of lured leaf on regional farm test in 1995-1997. KB 110 produced average yields of good quality tobaccos and was appeared to be resistant to PVY inwhere occurrence of the virus are severe chronic at burley growing area.

• Journal of Crop Science and Biotechnology
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• 제11권2호
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• pp.127-134
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• 2008

Tobamoviruses are the major viral pathogens of tomato and bell pepper. The preliminary results showed that Acibenzolar-Smethyl(ASM; S-methylbenzo(1,2,3) thiadiazole-7-carbothiate) pre-treatment to tomato and tobacco plants reduces the concentration of Tomato mosaic tobamovirus(ToMV) and Tobacco mosaic tobamovirus(TMV) in tomato and bell pepper seedlings, respectively. Pre-treatment of the indicator plant(Nicotiana glutinosa) with the ASM followed by challenge inoculation with tobamoviruses produced a reduced number and size of local lesions(67 and 79% protection over control to TMV and ToMV inoculation, respectively). In order to understand the mechanism of resistance the gene expression profiles of antiviral genes was examined. RT-PCR products showed higher expression of two viral resistance genes viz., alternative oxidase(AOX) and RNA dependent RNA polymerase(RdRp) in the upper leaves of the ASM-treated tomato plants challenge inoculation with ToMV. Further, the viral concentration was also quantified in the upper leaves by reverse transcription PCR using specific primer for movement protein of ToMV, as well as ELISA by using antisera against tobamoviruses. The results provided additional evidence that ASM pre-treatment reduced the viral movement to upper leaves. The results suggest that expressions of viral resistance genes in the host are the key component in the resistance against ToMV in the inducer-treated tomato plants.

• BMB Reports
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• 제41권5호
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• pp.376-381
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• 2008

The discovery of RNA silencing inhibition by virus encoded suppressors or low temperature leads to concerns about the stability of transgenic resistance. RNA-dependent RNA polymerase (RdRp) has been previously characterized to be essential for transgene-mediated RNA silencing. Here we showed that low temperature led to the inhibition of RNA silencing, the loss of viral resistance and the reduced expression of host RdRp homolog (NtRdRP1) in transgenic T4 progeny with untranslatable potato virus Y coat protein (PVY-CP) gene. Moreover, RNA silencing and the associated resistance were differently inhibited by potato virus X (PVX) and tobacco mosaic virus (TMV) infections. The increased expression of NtRdRP1 in both PVX and TMV infected plants indicated its general role in response to viral pathogens. Collectively, we propose that biotic and abiotic stress factors affect RNA silencing-mediated resistance in transgenic tobacco plants and that their effects target different steps of RNA silencing.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.567-573
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• 2010

To ascertain the effect of over-expressed maize calreticulin in tomato plant on tobamovirus movement in addition to validating potentiality of the gene (ZmCRT) as a means for the virus-resistance resource, four ZmCRT-expressing homozygous lines were generated from the T0 plants as using an Agrobacterium-mediated transformation, nucleic acid analyses, and a conventional breeding method. Of them, a line was subjected to the bioassay for tolerances to tobacco mosaic virus-U1 (TMV-U1) and tomato mosaic virus (ToMV) followed by RT-PCR and a chlorophyll fluorescence quenching analyses. Both transgenic plants transcribing ZmCRT and wild-type plants showed no symptom by 20 days after viruses inoculation, however the photosystem II quantum yield parameter measured from the upper leaves of ToMV-inoculated plants revealed that ZmCRT transgenic plants have higher photosynthetic ability than wild-type ones at that time, which indirectly implies that over-expressed ZmCRT product acts as a barrier to the cell-to-cell and/or systemic movement of ToMV. Moreover, ZmCRT transgenic plants showed remarkably longer shoot length than wild-type ones in 40 days after TMV-U1 or ToMV inoculation each, which might be resulted from higher photosynthetic ability during the phase not yet showing any external symptoms. Collectively, over-expressed ZmCRT protein in tomato plants is able to interrupt the systemic movement of infected TMV-U1 and ToMV even though not perfect.

• The Plant Pathology Journal
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• 제36권1호
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• pp.1-10
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• 2020

Since salicylic acid (SA) was discovered as an elicitor of tobacco plants inducing the resistance against Tobacco mosaic virus (TMV) in 1979, increasing reports suggest that SA indeed is a key plant hormone regulating plant immunity. In addition, recent studies indicate that SA can regulate many different responses, such as tolerance to abiotic stress, plant growth and development, and soil microbiome. In this review, we focused on the recent findings on SA's effects on resistance to biotic stresses in different plant-pathogen systems, tolerance to different abiotic stresses in different plants, plant growth and development, and soil microbiome. This allows us to discuss about the safe and practical use of SA as a plant defense activator and growth regulator. Crosstalk of SA with different plant hormones, such as abscisic acid, ethylene, jasmonic acid, and auxin in different stress and developmental conditions were also discussed.