• 한국식물병리학회지
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• 제11권4호
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• pp.374-379
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• 1995

The cDNA of tobacco mosaic virus-pepper strain (TMV-P) coat protein (CP) genes were introduced into tobacco plants (Nicotiana tabacum cv. Samsun nn) using a binary Ti plasmid vector of Agrobacterium tumefaciens. these cDNAs introduced into tobacco plants were detected by polymerase chain reaction. Symptom development was distinctly suppressed in the transgenic plant introduced buy sense CP cDNA when the plant was inoculated with TMV-P, while in transgenic tobacco plants of antisense CP gene, symptom development was not suppressed as in non-transgenic plants. TMV-P concentration in the sense CP transgenic tobacco plant was decreased to 1/14 of the concentration in non-transgenic plants. Expression of the kanamycin resistance gene of these transgenic plants could be detected in the progeny.

• 식물병연구
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• 제26권2호
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• pp.103-108
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• 2020

치즈 제조공정에서 나오는 부산물인 유청이 진딧물에 의해 전염되는 오이모자이크바이러스(cucumber mosaic virus, CMV)와 고추모틀바이러스(pepper mottle virus, PepMoV)의 감염 억제효과가 있는지를 고추 '청양' 품종을 대상으로 조사하였다. 온실에서 유청 원액 및 원액을 물로 2-20배로 희석하여 고추 '청양' 품종에 분무한 후 복숭아혹진딧물을 이용하여 CMV-Vch를 접종한 결과, 원액을 처리한 실험 구의 감염률이 6.6%로, 대조로 물을 처리한 실험 구의 감염률 23.3%에 비해 저하되었다. 노지에서 재배하는 고추 '청양' 품종에 CMV는 인위적으로 접종하지 않고 자연 감염되도록 둔 상태에서 정식일부터 6월 말일까지 1주일 간격으로 유청 원액을 분무 처리한 결과, 6월5일 이전에 자연적으로 CMV에 감염된 식물체의 비율이 무처리와 살충제 처리에 비해 각각 18.9%와 16.7% 감소하였다. 유청의 식물 바이러스 감염억제에 대한 작용 기작을 알기 위하여 온실에서 PepMoV-kr에 감염된 식물체 즙액과 유청을 1:1로 혼합하여 고추에 인공접종하여 시간경과에 따른 외피단백질 농도 변화를 웨스턴 블로팅 방법으로 분석한 결과, 접종 6일 후 대조에 비하여 적었으나, 접종 9일 후에는 대조와 동일하게 증가하였다. 본 연구 결과는 유청이 고추에 발생하는 서로 다른 속에 속하는 두 종류의 바이러스인 CMV와 PepMoV에 의한 감염 억제에 효과가 있다는 것을 보여주었다.

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1542-1550
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• 2016

This is the first report that paromomycin, an antibiotic derived from Streptomyces sp. AG-P 1441 (AG-P 1441), controlled Phytophthora blight and soft rot diseases caused by Phytophthora capsici and Pectobacterium carotovorum, respectively, in chili pepper (Capsicum annum L.). Chili pepper plants treated with paromomycin by foliar spray or soil drenching 7 days prior to inoculation with P. capsici zoospores showed significant (p < 0.05) reduction in disease severity (%) when compared with untreated control plants. The disease severity of Phytophthora blight was recorded as 8% and 50% for foliar spray and soil drench, respectively, at 1.0 ppm of paromomycin, compared with untreated control, where disease severity was 83% and 100% by foliar spray and soil drench, respectively. A greater reduction of soft rot lesion areas per leaf disk was observed in treated plants using paromomycin (1.0 μg/ml) by infiltration or soil drench in comparison with untreated control plants. Paromomycin treatment did not negatively affect the growth of chili pepper. Furthermore, the treatment slightly promoted growth; this growth was supported by increased chlorophyll content in paromomycin-treated chili pepper plants. Additionally, paromomycin likely induced resistance as confirmed by the expression of pathogenesis-related (PR) genes: PR-1, β-1,3-glucanase, chitinase, PR-4, peroxidase, and PR-10, which enhanced plant defense against P. capsici in chili pepper. This finding indicates that AG-P 1441 plays a role in pathogen resistance upon the activation of defense genes, by secretion of the plant resistance elicitor, paromomycin.

• The Plant Pathology Journal
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• 제15권4호
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• pp.217-222
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• 1999

Treatment with antagonistic rhizobactera Burkholderia cepacia strain N9523 or an inducer of resistance DL-$\beta$-amino-n-butyric acid (BABA) effectively inhibited Phytophthora capsici infection on pepper plants in artificially infested pots. Treatment with BABA alone at $1,000\mu\textrm{g}$/ml or together with B. cepacia in combination induced a strong protection from the Phytophthora disease in the greenhouse. In artificially infested field, protection of pepper plants against the Phytophthora epidemic by BABA treatment was maintained at a considerable level. In contrast, soil drench with the antagonist B. cepacia alone, or in combination with BABA did not suppress the Phytophthora epidemic in the field. Mortality of pepper plants caused by P. capsici infection was significantly reduced by treatment with the antagonist Pseudomonas aeruginosa strain 950923-29 and BABA (12-29% plants diseased) relative to the untreated control (41-91% plants diseased) in the naturally infested field. Treatment with the antagonist Ps. aeruginosa strain 950923-29 and BABA also resulted in high levels of protection against Phytophthora blight in pepper plants. In the plastic filmhouse test, the average percentage of plants diseased was significantly low relative to the naturally infested field. Treatment with the antagonist Ps. aeruginosa strain 950923-29 and BABA in combination was most effective in suppressing the Phytophthora disease in field and plastic filmhouse.

• The Plant Pathology Journal
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• 제21권3호
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• pp.195-206
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• 2005

Spatial and temporal expression of pathogenesis-related (PR) gene and proteins has been recognized as inducible defense response in pepper plants. Gene expression and/or protein accumulation of PR-1, $\beta-1,3-glucanase$ and chitinase was predominantly found in pepper plants during the inoculations by Xanthomonas campestris pv. vesicatoria, Phytophthora capsici and Colletotrichum coccodes. PR-1 and chitinase genes were also induced in pepper plants in response to environmental stresses, such as high salinity and drought. PR-1 and chitinase gene expressions by biotic and abiotic stresses were regulated by their own promoter regions containing several stress-related cis-acting elements. Overexpression of pepper PR-1 or chitinase genes in heterogeneous transgenic plants showed enhanced disease resistance as well as environmental stress tolerances. In this review, we focused on the putative function of pepper PR-1, $\beta-1,3-glucanase$ and chitinase proteins and/or genes at the biochemical, molecular and cytological aspects.

• The Plant Pathology Journal
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• 제32권5호
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• pp.431-440
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• 2016

In 2004, bacterial spot-causing xanthomonads (BSX) were reclassified into 4 species-Xanthomonas euvesicatoria, X. vesicatoria, X. perforans, and X. gardneri. Bacterial spot disease on pepper plant in Korea is known to be caused by both X. axonopodis pv. vesicatoria and X. vesicatoria. Here, we reidentified the pathogen causing bacterial spots on pepper plant based on the new classification. Accordingly, 72 pathogenic isolates were obtained from the lesions on pepper plants at 42 different locations. All isolates were negative for pectolytic activity. Five isolates were positive for amylolytic activity. All of the Korean pepper isolates had a 32 kDa-protein unique to X. euvesicatoria and had the same band pattern of the rpoB gene as that of X. euvesicatoria and X. perforans as indicated by PCR-restriction fragment length polymorphism analysis. A phylogenetic tree of 16S rDNA sequences showed that all of the Korean pepper plant isolates fit into the same group as did all the reference strains of X. euvesicatoria and X. perforans. A phylogenetic tree of the nucleotide sequences of 3 housekeeping genes-gapA, gyrB, and lepA showed that all of the Korean pepper plant isolates fit into the same group as did all of the references strains of X. euvesicatoria. Based on the phenotypic and genotypic characteristics, we identified the pathogen as X. euvesicatoria. Neither X. vesicatoria, the known pathogen of pepper bacterial spot, nor X. perforans, the known pathogen of tomato plant, was isolated. Thus, we suggest that the pathogen causing bacterial spot disease of pepper plants in Korea is X. euvesicatoria.

• 식물병연구
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• 제19권3호
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• pp.208-215
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• 2013

3-(4-Hydroxyphenyl)-propionic acid (HPP)는 곤충 병원 세균인 Xenorhabdus nematophila K1의 대사산물이다. 이 물질의 고추의 역병과 탄저병에 대한 방제가능성을 평가하였다. HPP는 역병균과 탄저병균의 균사생장을 현저하게 억제하였다. 이 항균력은 자연 태양광 아래에서 25일이상 유지되었으며, 토양수 내에서도 상실되지 않았다. HPP의 고추 뿌리를 통한 식물체 내 침투 및 상향이행성이 입증되었다. HPP 현탁액을 고추의 근권토양에 관주하고 지상부에 10일 간격으로 살포하였을 때, 약해 발생 없이 역병과 탄저병 발생이 크게 감소되었다. 이러한 결과는 HPP를 고추 역병 및 탄저병 방제를 위한 침투성농약으로 개발할 가능성이 있음을 의미한다.

• The Plant Pathology Journal
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• 제15권6호
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• pp.319-322
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• 1999

In order to obtain bacterial metabolites inducing disease resistance in pepper plant, two hundred bacterial isolates were isolated from the rhizosphere soil of tobacco, cucumber, and pepper plant. Ethyl acetate extract of each bacterial culture was used to screening for induction of resistance against phytophthora blight of pepper plant. Application of ethyl acetate extract of an isolate SH122 culture to pepper plant conferred resistance against phytophthora blight consistently and significantly. According to cellular fatty acid analysis and other characteristics, the SH122 culture were significantly lower than those on control plants treated with ethyl acetate extract of nutrient broth. The B. pumilus SH122 itself of ethyl acetate extract of its culture did not show antifungal activity against phytophthora blight in pepper plants.

• 한국식물병리학회지
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• 제14권6호
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• pp.741-743
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• 1998

A bacterial disease of pepper (Capsicum annuum L.) that rooted the stem nodes to black was found in pepper plants which cultivated in plastic house at Chungdo, Kyungpook, Korea in March, 1998. Bacterial isolates derived from the diseased peppers were pathogenic to potato, eggplant and Chinese cabbage but, was not pathogenic to chrysanthemum by artificial inoculation. On the basis of bacteriological characteristics and pathogenicity test on host plants, the causal organism of the node soft rot of pepper is identified as Erwinia carotovora subsp. carotovora and the name of disease is proposed as bacterial node soft rot of pepper.

• 한국식물병리학회지
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• 제14권5호
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• pp.440-444
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• 1998

This experiment was carried out to elucidate the effect of electrolytic water on the growth and infection of Phytophthora capsici. Zoospores of P. capsici did not grow on potato dextrose agar when the pathogen was cultured after suspended in electrolytifc water (pH 2.5, 3.0, 3,5) with HCI solution. When the 100 ml of electrolytic water (pH 2.5, 3.0, 3.5) was irrigated on the red pepper plants that had been inoculated by P. capsici (103 zoospores/ml), the red pepper plants were not infected but irrigated with sterilized water (pH 6.5) the red pepper plants were infected. With this result, it could be concluded that the good sterilization effect on P. capsici might be obtained by applying electrolytic water.