• The Plant Pathology Journal
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• 제23권4호
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• pp.239-244
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• 2007

MicroTom is a miniature tomato plants with various properties that make it as a model system for experiments in plant molecular biology. To extend its utility as a model plant to study a plant - bacterial wilt system, we investigated the potential of the MicroTom as a host plant of bacterial wilt caused by Ralstonia solanacearum. We compared the disease progress on standard tomato and MicroTom by two inoculation methods, root dipping and soil drenching, using a race 1 strain GMI1000. Both methods caused the severe wilting on MicroTom comparable to commercial tomato plant, although initial disease development was faster in root dipping. From the diseased MicroTom plants, the same bacteria were successfully reisolated using semiselective media to fulfill Koch's postulates. Race specific and isolate specific virulence were investigated by root dipping with 10 isolates of R. solanacearum isolated from tomato and potato plants. All of the tested isolates caused the typical wilt symptom on MicroTom. Disease severities by isolates of race 3 was below 50 % until 15 days after inoculation, while those by isolates of race 1 reached over 50% to death until 15 days. This result suggested that MicroTom can be a model host plant to study R. solanacearum - plant interaction.

• 원예과학기술지
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• 제29권4호
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• pp.336-344
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• 2011

Using the abundant available information about the tomato genome, we developed DNA markers that are linked to disease resistant loci and performed marker-assisted selection (MAS) to construct multi-disease resistant lines and varieties. Resistance markers of Ty-1, T2, and I2, which are linked to disease resistance to Tomato yellow leaf curl virus (TYLCV), Tomato mosaic virus (ToMV), and Fusarium wilt, respectively, were developed in a co-dominant fashion. DNA sequences near the resistance loci of TYLCV, ToMV, and Fusarium wilt were used for primer design. Reported candidate markers for powdery mildew-resistance were screened and the 32.5Cla marker was selected. All four markers (Ty-1, T2, I2, and 32.5Cla) were converted to cleavage amplification polymorphisms (CAPS) markers. Then, the CAPS markers were applied to 96 tomato lines to determine the phenetic relationships among the lines. This information yielded clusters of breeding lines illustrating the distribution of resistant and susceptible characters among lines. These data were utilized further in a MAS program for several generations, and a total of ten varieties and ten inbred lines were constructed. Among four traits, three were introduced to develop varieties and breeding lines through the MAS program; several cultivars possessed up to seven disease resistant traits. These resistant trait-related markers that were developed for the tomato MAS program could be used to select early stage seedlings, saving time and cost, and to construct multi-disease resistant lines and varieties.

• 식물병연구
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• 제14권1호
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• pp.32-36
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• 2008

Ralstonia solanacearum에 의한 풋마름병은 토마토, 감자 등의 작물에 심각한 피해를 주고 있으나, 효과적인 방제법이 없는 실정이다. 일반 병원균의 생물적 방제를 위해 Pseudomonas속의 세균이 가장 일반적으로 이용되고 있는데, 이번 연구에서는 각종 작물의 재배지 토양에서 형광성 세균을 분리하여 Pseudomonas속 특이적 PCR과 항생물질(2,4-diacetylphloroglucinol) 생산 관련 유전자의 유무를 조사하였다. 분리된 150개의 Pseudomonas속 세균 중 항생물질 관련 유전자가 검출된 균은 2균주뿐이였으며, 그중 토마토 근권토양으로 분리된 P. putida P84 세균이 각종 식물 병원 세균에 대해 가장 높은 실내 항균력을 나타내었다. P84 균주의 탄소원별 증식효과는 glucose 첨가시에 가장 좋았으며, arabionse, inositol, melibiose 첨가시에도 우수한 증식효과를 나타내었다. P84세균을 이용한 토마토 풋마름병의 포트실험 결과에서는 60%의 방제효과를 나타내었다.

• The Plant Pathology Journal
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• 제28권1호
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• pp.32-39
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• 2012

Efficacy of different control methods was evaluated for disease management of tomato bacterial wilt caused by $Ralstonia$ $solanacearum$. All six chemical pesticides applied to the bacterial suspension showed $in$ $vitro$ bactericidal activities against $R.$ $solanacearum$. Minimal inhibitory concentrations (MICs) of copper hydroxide (CH), copper hydroxide-oxadixyl mixture (CH+O), and copper oxychloride-dithianon mixture (CO+D) were all 200 ${\mu}g/ml$; MIC of copper oxychloride-kasugamycin (CO+K) mixture was 100 ${\mu}g/ml$; MICs of both streptomycin- validamycin (S+V) and oxine copper-polyoxine B mixture (OC+PB) were 10 ${\mu}g/ml$. Among these chemical pesticides, treatment of the detached tomato leaves with the 5 pesticides (1 mg/ml), except for OC+PB delayed early wilting symptom development caused by the bacterial inoculation ($10^6$ and $10^7$ cfu/ml). Four pesticides, CH, CH+O, CO+K and S+V, showed disease protection in pot analyses. Six plant essential oils, such as cinnamon oil, citral, clove oil, eugenol, geraniol and limonene, differentially showed their antibacterial activities $in$ $vitro$ against $R.$ $solanacearum$ demonstrated by paper disc assay. Among those, cinnamon oil and clove oil exert the most effective activity for protection from the wilt disease caused by the bacterial infection ($10^6$ cfu/ml). Treatment with cinnamon oil and clove oil also suppressed bacterial disease by a higher inoculum concentration ($10^7$ cfu/ml). Clove oil could be used for prevention of bacterial wilt disease of tomato plants without any phytotoxicity. Thus, we suggest that copper compounds, antibiotics and essential oils have potency as a controlling agent of tomato bacterial wilt.

• The Plant Pathology Journal
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• 제20권4호
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• pp.297-301
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• 2004

A Tomato spotted wilt virus (TSWV-KP) was isolated from Paprika (Capsicum annuum var. grossum) showing necrosis spot on the leaves and malformation of the fruit in Yesan, Korea. The virus infected Chenopodium amaranticolor, C. quinoa, Petunia hybrida, Nicotiana glutunosa, Gomphrena globosa, and Physalis floridana. Ten plants including tomato were observed to have systemic TWSV-KP infection. The virus produced necrosis or necrotic ring spots on the inoculated leaves and mosaic, vein necrosis or death on the upper leaves of Datura stramonium, N. clevarandii, N. rustica, and N.tabacum cvs. Thin sections of the infected leaf tissue contained spherical to oval particles, a characteristic of a Tospovirus. The virion contained three molecules of genomic RNAs, which were approximately 9.0, 4.9 and 3.0 kb. The nucleocapsid (N) protein of the purified virion migrated as a single band with molecular weight of about 29 kDa in SDS-PAGE. The N gene of TSWV-KP showed 96.5-97.2% and 97.7-98.5% identities to the three different TSWV isolates of Genbank Database at the nucleotide and amino acid, respectively.

• 한국식물병리학회지
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• 제14권3호
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• pp.278-285
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• 1998

Effects of chitosan on growth of tomato plant, and suppression of Fusaruim wilt caused by Fusarium oxysporum f. sp. lycopersici and late blight casued by Phytophthora infestans, were examined. Both late blight and fusarium wilt were suppressed by spray and irrigation of chitosan, respectively. Inhibition of mycelial growth was not greatly affected by molecular size of chitosan but, concentration dependent effects was observed. Ninty percent of P. infestans and 80% of F. oxysporum f. sp. lycopersici of mycelial growth was inhibited by 1,000 ppm of chitosan (MW 30,000~50,000) when amended in plate media. Induction of defense-related gene expression in plant by chitosan treatments were observed when chitosan treated tobacco and tomato RNA samples were hybridized with several defense-related genes as probes. The results revealed that $\beta$-1,3-glucanase and chitinase genes were strongly induced, while pathogenesis-related protein-1, 3-hydroxy-3-methylglutaryl coenzyme A reductase, anionic peroxidase, phenylalanine ammonia lyase genes were weakly induced by chitosan treatment. These results suggest that chitosan have dual effects on these host-pathogen interactions. Possible roles of chitosan in suppression of tomato diseases by inhibition of mycelial growth and activation of plant defense responses are discussed.

• The Plant Pathology Journal
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• 제27권4호
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• pp.390-395
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• 2011

Fusarium wilt caused by Fusarium oxysporum has become a serious problem world-wide and relies heavily on chemical fungicides. We selected Pseudomonas sp. NJ134 to develop an effective biocontrol strategy. This strain shows strong antagonistic activity against F. oxysporum. Biochemical analyses of ethyl-acetate extracts of NJ134 culture filtrates showed that 2,4-diacetylphloroglucinol (DAPG) was the major compound inhibiting in vitro growth of F. oxysporum. DAPG production was greatly enhanced in the NJ134 strain by adding mannitol to the growth media, and in vitro antagonistic activity against F. oxysporum increased. Bioformulations developed from growth of NJ134 in sterile bean media with mannitol as the carbon source under plastic bags resulted in effective biocontrol efficacy against Fusarium wilt. The efficacy of the bioformulated product depended on the carbon source and dose. Mannitol amendment in the bean-based formulation showed strong effective biocontrol against tomato Fusarium wilt through increased DAPG levels and a higher cell density compared to that in a glucose-amended formulation. These results suggest that this bioformulated product could be a new effective biocontrol system to control Fusarium wilt in the field.

• 한국균학회지
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• 제44권4호
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• pp.318-322
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• 2016

노루궁뎅이(Hericium erinaceus) 수확 후 배지를 추출한 시제품 알토엑스 + 질산칼슘, 케이칼슘과 알토엑스베타는 토마토 풋마름병균에 대하여 강한 항균활성을 나타내었다. 토마토 풋마름병에 대하여 알토엑스 + 질산칼슘, 케이칼슘과 알토엑스베타가 87.4~100%, 46.0~100%, 65.0~91.6%의 방제효과를 각각 나타내었다. 이들 결과들은 알토엑스 + 질산칼슘, 케이칼슘과 알토엑스베타가 토마토 풋마름병 방제를 위한 유망한 친환경 세균제가 될 것으로 생각된다.

• The Plant Pathology Journal
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• 제39권5호
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• pp.430-448
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• 2023

Recently, strategies for controlling Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of Fusarium wilt of tomato, focus on using effective biocontrol agents. In this study, an analysis of the biocontrol and plant growth promoting (PGP) attributes of 11 isolates of loamy soil Bacillus spp. has been conducted. Among them, the isolates B.PNR1 and B.PNR2 inhibited the mycelial growth of Fol by inducing abnormal fungal cell wall structures and cell wall collapse. Moreover, broad-spectrum activity against four other plant pathogenic fungi, F. oxysporum f. sp. cubense race 1 (Foc), Sclerotium rolfsii, Colletotrichum musae, and C. gloeosporioides were noted for these isolates. These two Bacillus isolates produced indole acetic acid, phosphate solubilization enzymes, and amylolytic and cellulolytic enzymes. In the pot experiment, the culture filtrate from B.PNR1 showed greater inhibition of the fungal pathogens and significantly promoted the growth of tomato plants more than those of the other treatments. Isolate B.PNR1, the best biocontrol and PGP, was identified as Bacillus stercoris by its 16S rRNA gene sequence and whole genome sequencing analysis (WGS). The WGS, through genome mining, confirmed that the B.PNR1 genome contained genes/gene cluster of a nonribosomal peptide synthetase/polyketide synthase, such as fengycin, surfactin, bacillaene, subtilosin A, bacilysin, and bacillibactin, which are involved in antagonistic and PGP activities. Therefore, our finding demonstrates the effectiveness of B. stercoris strain B.PNR1 as an antagonist and for plant growth promotion, highlighting the use of this microorganism as a biocontrol agent against the Fusarium wilt pathogen and PGP abilities in tomatoes.

• 식물병연구
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• 제11권2호
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• pp.213-216
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• 2005

토마토 반점위조 바이러스(Tomato spotted wilt virus; TSWV)가 2004년 경기도 안양지역에서 토마토, 고추 등을 포함한 14개 채소 작물에서 발생하였다. TSWV검정은 지표식물 검정, IC/RT-PCR, VC/RT-PCR 및 Total RNA를 이용한 RT-PCR방법을 이용하였으며, TSWV가 발생한 작물의 종류는 토마토, 방울 토마토, 고추, 시금치, 치커리, 적치커리, 적겨자, 용설채, 트레비소, 감자, 들깨, 참깨, 호박, 쌈추 이었다. 포장에서의 발생율은 토마토, 고추 등 주요 작물에서 $30\%$에서 $100\%$ 발생하였으며,병징은 대부분 전형적인 원형반점이었으며, 괴저, 위조 및 심한 모자이크 병징으로 진전되었다. TSWV가 발생한 포장에서 채집한 꽃노랑 총채벌레(Frankliniella occidentalis)를 IC/RT-PCR 검정한 결과 감염율이 $90\%$이었다.