• 한국식물병리학회지
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• 제14권4호
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• pp.319-324
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• 1998

Induction of systemic acquired resistance (SAR) against phytophthora blight and pathogenesis-related (PR) protein accumulation by TMV infection in pepper plant (Capsicum annuum cv. Nockwang) were examined to understand the mechanism of the systemic acquired resistance in pepper plant. The zoospore suspension of Phytophthora capsici was inoculated on stem of pepper plant in which TMV-pepper strain had been inoculated on fully expanded upper leaves, and thephytopha blight incidence was examined. Both disease severity and lesion length of phytophthora blight were much smaller in TMV pre-inoculated pepper plant than in uninoculated control plants. The phytophthora blight incidence was decreased about 50% in the TMV pre-inoculated pepper, compared to the uninoculated control plant at 10 days after P. capsici inoculation. Accumulation of PR1 and PR5 proteins in intercellular fluid of TMV-inoculated and uninoculated upper leaves were monitored by immuno-blot with tobacco P1b and PR5a, antibody during induction of SAR. PR1 and PR5 were detected from 24 hours after TMV inoculation in both TMV-inoculated and uninouclated upper leaves, and increased rapidly in TMV-inoculation in uninoculated upper leaves were defoliated. PR5 could be detected upto 20 days after TMV inoculation in uninoculated upper leaves. These results suggest that TMV infection induces SAR against phytophthora blight in pepper plant, and that PR proteins are accumulated very rapidly during induction of SAR and maintained for quite long time in pepper plant.

• 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.

• The Plant Pathology Journal
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• 제18권4호
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• pp.221-224
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• 2002

In vitro and in vivo activities of a biocontrol agent, Serratia plymuthica strain A2l-4, was evaluated for the control of Phytophthora blight of pepper, Strain A2l-4 inhibited mycelial growth, germination of zoosporangia and cystospores, and formation of zoospore and zoosporangia of Phytophthora capsici in vitro. In the pot experiment, incidence of Phytophthora blight of pepper in non-treated control was 100% at 14 days after inoculation, while no disease was observed in the plot treated with S. plymuthica A2l-4. In the greenhouse test, infection rate of pepper in the non-treated plots was 74.5%, while it was only 12.6％ in the plots treated with A2l-4. Results indicate that S. plymuthica A2l-4 is a potential biocontrol agent for Phytophthora blight of pepper.

• 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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• 제33권3호
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• pp.264-275
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• 2017

The spent mushroom substrate (SMS) of Lentinula edodes that was derived from sawdust bag cultivation was used as materials for controlling Phytophthora blight disease of pepper. Water extract from SMS (WESMS) of L. edodes inhibited mycelial growth of Phytophthora capsici, suppressed Phytophthora blight disease of pepper seedlings by 65% and promoted growth of the plant over 30%. In high performance liquid chromatography (HPLC) analysis, oxalic acid was detected as the main organic acid compound in WESMS and inhibited the fungal mycelium at a minimum concentration of 200 mg/l. In quantitative real-time PCR, the transcriptional expression of CaBPR1 (PR protein 1), CaBGLU (${\beta}$-1,3-glucanase), CaPR-4 (PR protein 4), and CaPR-10 (PR protein 10) were significantly enhanced on WESMS and DL-${\beta}$-aminobutyric acid (BABA) treated pepper leaves. In addition, the salicylic acid content was also increased 4 to 6 folds in the WESMS and BABA treated pepper leaves compared to water treated leaf sample. These findings suggest that WESMS of L. edodes suppress Phytophthora blight disease of pepper through multiple effects including antifungal activity, plant growth promotion, and defense gene induction.

• 한국유기농업학회지
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• 제28권4호
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• pp.579-589
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• 2020

고추역병 다발생 포장에서 녹비작물인 호밀재배에 따른 토양환경 변화와 고추역병 경감 효과를 조사하였다. 토양 물리성을 분석한 결과에서는 호밀재배에서 용적밀도와 공극률이 증가하였다. 또한, 토양 삼상의 분포는 고상에서는 관행재배와 차이가 없었으나, 기상은 관행재배 보다 증가하고 액상은 감소하였다. 토양 내 인지질 지방산을 추출하여 지표 지방산으로 분석한 미생물 군락의 상대밀도는 호밀재배에서 유의성 있게 증가하였으며, 호기성균/혐기성균의 비율의 비율도 호밀재배에서 높게 나타났다. 환경스트레스 지표인 포화지방산/불포화지방산 비율과 cyclo-지방산/전구체 비율은 호밀재배가 관행재배 보다 낮아 토양환경이 개선 된 것으로 나타났다. 호밀재배에 따른 고추역병의 경감효과를 조사한 결과 호밀재배가 관행재배 보다 30.7% 낮은 발병률을 나타냈다. 이상의 결과를 요약해볼 때, 고추역병 다발생 포장에서 녹비작물인 호밀재배는 토양환경을 개선하고 고추역병 발병을 감소시킬 것으로 사료된다.

• The Plant Pathology Journal
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• 제15권1호
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• pp.48-52
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• 1999

Ethaboxam is the first proprietary fungicide developed in Korea, registered in 1998 and commercialized in 1999 by LG Chemical Ltd., Korea. It is a derivative of aminothiazole carboxamide and formulated into 25% wettable powder for practical application in fields. Ethaboxam effectively controlled cucumber downy mildew caused by Pseudoperonospora cubensis, potato late blight caused by Phytophthora infestans, and pepper Phytophthora blight caused by P. capsici, and was superior or comparable to the commercial standards, when foliarly sprayed 3∼5 times until dripping off at approximately 7-day intervals during the growing season. Ethaboxam was required at least 125 mg/liter and 250 mg/liter for effective control of cucumber downy mildew, and potato late blight and pepper Phytophthora blight, respectively. There was not phytotoxicity observed o leaves, stems or fruits of cucumber, potato and pepper from any trial.

• The Plant Pathology Journal
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• 제26권4호
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• pp.367-371
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• 2010

In this study, we evaluated the efficacy of fluopicolide to inhibit Phytophthora capsici in vitro, and to control pepper Phytophthora blight in a greenhouse and pepper fields. Fluopicolide was tested on various developmental stages of P. capsici 06-143 (a sensitive isolate to metalaxyl) and JHAW1-2 (a resistant isolate to metalaxyl). Mycelial growth and zoosporangium germination of both isolates were completely inhibited at $4.0\;{\mu}g/ml$ of the fungicide in vitro. The $EC_{50}$ (effective concentrations reducing 50%) of P. capsici 06-143 against zoospore were $0.219\;{\mu}g/ml$, while those of JHAW1-2 were $3.829\;{\mu}g/ml$. When fluopicolide was applied at 100 and $1,000\;{\mu}g/ml$ 7 days before inoculation with P. capsici 06-143 in the greenhouse test, the disease was controlled completely until 6 days after inoculation. However, the curative effect of fluopicolide was not as much as the protective effect. When fluopicolide was applied by both soil drenching and foliar spraying, the treatments strongly protected pepper against the Phytophthora blight disease. Based on these results, fluopicolide can be a promising candidate for a fungicide to control P. capsici in the pepper fields.

• 식물병연구
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• 제16권1호
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• pp.106-108
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• 2010

노지피복 재배포장과 비닐터널유인 재배포장의 재배양식별 고추 탄저병과 역병의 발생정도를 조사하였다. 비닐터널유인재배포장의 초기 생육이 노지피복재배포장(관행)보다 월등히 우세하였다. 재배 양식별 고추 주요 병해인 탄저병과 역병의 발생정도를 조사한 결과 노지피복재배포장에 비해 터널유인 재배한 포장에서 역병발생은 60.3%, 탄저병발생은 26.9% 경감효과가 있었다. 재배양식별 건과 수확량을 조사한 결과 노지피복 재배포장대비 48.5%가 많은 것으로 조사되었다.

• The Plant Pathology Journal
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• 제28권2호
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• pp.172-184
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• 2012

An infection risk model for Phytophthora blight on chili pepper was developed to estimate the first date of disease occurrence in the field. The model consisted of three parts including estimation of zoosporangium formation, soil water content, and amount of active inoculum in soil. Daily weather data on air temperature, relative humidity and rainfall, and the soil texture data of local areas were used to estimate infection risk level that was quantified as the accumulated amount of active inoculum during the prior three days. Based on the analysis on 190 sets of weather and disease data, it was found that the threshold infection risk of 224 could be an appropriate criterion for determining the primary infection date. The 95% confidence interval for the difference between the estimated date of primary infection and the observed date of first disease occurrence was $8{\pm}3$ days. In the model validation tests, the observed dates of first disease occurrence were within the 95% confidence intervals of the estimated dates in the five out of six cases. The sensitivity analyses suggested that the model was more responsive to temperature and soil texture than relative humidity, rainfall, and transplanting date. The infection risk model could be implemented in practice to control Phytophthora blight in chili pepper fields.