• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.195-199
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• 2010

This experiment was conducted to develop optimum sesame cultivation practices as succeeding cropping system of watermelon in the greenhouse condition. We also compared major components in sesame seed cultivated in the greenhouse and open field condition. The adaptable varieties under the greenhouse condition were white sesame 'Pyoungan' and black sesame 'Jinki' which showed higher yield and disease resistance. We also conducted several experiments to determine optimum sowing date, planting density and pinching time. Grain yields were statistically different according to the several sowing dates. In general, sesame sowing on June 30th showed higher grain yields than July 10th, July 20th and July 30th in the greenhouse. We also found out sesame cultivation practice with the row spacing of 40 cm and interplant spacing of 30 cm (a few branch type) or 40 cm (many branch type) showed higher yield than other treatments. Optimum pinching time was 25 days after first flowering in main stem when thousand seed weight and grain yield were highest. In the comparison of major components of sesame at the different cultivation conditions, sesame seeds cultivated in the greenhouse contained 4% much more oil content than open field condition. The lignan compounds, sesamin and sesamolin were also higher by 6% in the greenhouse than open field condition. It was concluded that sesame cultivation practices as succeeding cropping system of watermelon in the greenhouse condition guaranteed higher grain yield with less labor input which is now emerging alternative farming practice system in present aging rural society and will also give sesame cultivation farmers to increase net income in Korea.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.110.1-110
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• 2003

Control effect of grafting with rootstocks on Phythophthora blight of pepper was evaluated. The 40∼45 day old seedlings of five pepper cultivars, Wangdaeback, Jinmi, Boosa, Samsungcho and Pochunngchun, as a scion were grafted with ten species of root stocks. There wasn't graft incompatibility in all scion-root stock combinations. After 21 days from inoculation with Phytopkhora capsici, incidence of Phythophthora blight of plant grafted with Kataguruma, R-Safe, R-16, YCM 334 and SCM 334 of rootstocks tested was decreased by 64.6∼100％ compared to non-grafted plant whose disease severity was 3.7. However, plant grafted with Umsung native and Yeongdong native pepper was more sensitive to Phythophthora blight than non-grafed plant. Control effect by grafting was inversely proportional to virulence of inoculum and not significantly different among scion cultivars used. And resistant reaction of scion against Phytophthora blight was not affect that of scion-root stock plant in this study.

• The Korean Journal of Mycology
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• v.51 no.2
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• pp.141-146
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• 2023

Stem rot symptoms were observed in Gondre (Cirsium setidens) plants growing in a vinyl greenhouse in Taebaek, Korea during a disease survey in June 2022. The plants presented with dark brown to black rot on the stems at or above the soil line. Severely diseased plants displayed wilt and blight. Disease incidence among these plants ranged from 1 to 5%. Three isolates of Rhizoctonia sp. were obtained from the stem lesions of diseased plants. All isolates were identified as Rhizoctonia solani AG-2-2(IV) based on the morphological and cultural characteristics, results of the anastomosis test, and phylogenetic analysis. The pathogenicity of the isolates to Gondre plants was confirmed using an artificial inoculation test. The lesions induced by the inoculation test were similar to those observed in the investigated vinyl greenhouse. Here, we report a case of R. solani AG-2-2(IV) causing stem rot in Gondre.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.209-211
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• 1998

Black dot root rot occurred severely in greenhouse tomatoes in jangseong area of Korea in April, 1996. The causal fungus of the disease was identified as Colletotrichum coccodes based on the morphological and cultural characteristics. Pathogenicity tests revealed that isolates of the fungus were responsible for the disease, and two cultivars of cherry tomato were less susceptible to the disease than other cultivars of tomato and cherry tomato tested.

• The Plant Pathology Journal
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• v.25 no.4
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• pp.333-343
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• 2009

Here, we show that an endophytic bacterial strain, Enterobacter asburiae B1 exhibits the ability to elicit ISR in cucumber, tobacco and Arabidopsis thaliana. This indicates that strain B1 has a widespread ability to elicit ISR on various host plants. In this study, E. asburiae strain B1 did not show antifungal activity against tested major fungal pathogens, Colletotrichum orbiculare, Botrytis cinerea, Phytophthora capsici, Rhizoctonia solani, and Fusarium oxysporum. Moreover, the siderophore production by E. asburiae strain B1 was observed under in vitro condition. In greenhouse experiments, the root treatment of strain B1 significantly reduced disease severity of cucumber anthracnose caused by fungal pathogen C. orbiculare compared to nontreated control plants. By root treatment of strain B1 more than 50% disease control against anthracnose on cucumber was observed in all greenhouse experiments. Simultaneously, under the greenhouse condition, the soil drench of strain B1 and a chemical inducer benzothiadiazole (BTH) to tobacco plants induced GUS activity which is linked with activation of PR promoter gene. Furthermore, in Arabidopsis thaliana plants the soil drench of strain B1 induced the defense gene expression of PR1 and PDF1.2 related to salicylic acid and jasmonic acid/ethylene signaling pathways, respectively. In this study, for the main focus on root colonization by strain B1 associated with defense responses, bacterial cells of strain B1 was tagged with the gfp gene encoding the green fluorescent protein in order to determine the colonization pattern of strain B1 in cucumber. The gfp-tagged B1 cells were found on root surface and internal colonization in root, stem, and leaf. In addition to this, the scanning electron microscopy observation showed that E. asburiae strain B1 was able to colonized cucumber root surface.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.165-171
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• 2009

Biological control activity of Acremonium strictum BCP, a mycoparasite on Botrytis cinerea, was examined against six plant diseases such as rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew in growth chambers. The spore suspension of strain BCP showed strong control activities against five plant diseases except against wheat leaf rust. On the other hand, the culture filtrate of A. strictum BCP was effective in controlling only cucumber gray mold and barley powdery mildew. Further in vivo biocontrol activities of A. strictum BCP against tomato gray mold were investigated under greenhouse conditions. Control efficacy of the fungus on tomato gray mold increased in a concentration-dependent manner. Treatment of more than $1{\times}10^6$ spores/ml significantly controlled the disease both in tomato seedlings and in adult plants. The high disease control activity was obtained from protective application of the strain BCP, whereas the curative application did not control the disease. Foliar infections of B. cinerea were controlled with $1{\times}10^8$ spores/ml of A. strictum BCP applied up to 7 days before inoculation. In a commercial greenhouse, application of A. strictum BCP exhibited the similar control efficacy with fungicide procymidone (recommended rate, $500{\mu}g/ml$) against strawberry gray mold. These results indicate that A. strictum BCP could be developed as a biofungicide for Botrytis diseases under greenhouse conditions.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.519-521
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• 2020

Damping-off symptoms were frequently observed on young plants of Indian lettuce (Lactuca indica) grown in a farmer's vinyl greenhouse located in Goseong, Gangwon province of Korea during a disease survey in June 2019. The incidence of diseased plants in the vinyl greenhouse investigated was 30-50%. Four isolates of Rhizoctonia sp. were obtained from the diseased plants and identified as Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on Indian lettuce by artificial inoculation. All the tested isolates induced damping-off symptoms on the inoculated plants. The symptoms were similar to those observed in plants from the farmer's vinyl greenhouse investigated. This is the first report of R. solani AG-4 causing damping-off in Indian lettuce.

• The Korean Journal of Mycology
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• v.49 no.2
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• pp.249-251
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• 2021

Damping-off symptoms were frequently observed in young deltoid synurus (Synurus deltoides) plants grown in a farmer's vinyl greenhouse located in Hwacheon, Gangwon Province, Korea, during a disease survey in July 2019. The incidence of diseased plants in the vinyl greenhouse investigated was 5-30%. Five isolates of Rhizoctonia sp. were obtained from the diseased plants and identified as Rhizoctonia solani AG-1 (IB), based on morphological and cultural characteristics and anastomosis test results. Three isolates of R. solani AG-1 (IB) were tested for pathogenicity on deltoid synurus using artificial inoculation. All the tested isolates induced damping-off symptoms in the inoculated plants. The symptoms were similar to those observed in plants from the farmer's vinyl greenhouse. To our best knowledge, this is the first report of R. solani AG-1 (IB) causing damping-off in deltoid synurus.

• Research in Plant Disease
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• v.28 no.2
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• pp.108-111
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• 2022

In December 2020, stem and leaf rot symptoms in small-fruited tomato (Solanum lycopersicum) plants were observed in a farmer's vinyl greenhouse located in Pyeongtaek, Gyeonggi Province, Korea. The incidence of diseased plants in the vinyl greenhouse was 2-6%. Seven single-spore isolates of Phoma sp. were obtained from the diseased stems and leaves. All the isolates were identified as Boeremia linicola based on the cultural, morphological and molecular characteristics. Two isolates of B. linicola were tested for pathogenicity on stems and leaves of small-fruited tomato and large-fruited tomato using artificial inoculation. All the tested isolates caused stem and leaf rot symptoms in the inoculated plants. The symptoms were similar to those observed in plants from the vinyl greenhouse investigated. This is the first report of B. linicola causing stem and leaf rot in tomato.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.486-495
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• 2020

We surveyed disease outbreak status that has recently become a problem in organic tomatoes and cucurbit in plastic greenhouse that were grown without spraying pesticides during the plastic greenhouse growing season of 2015 to 2019. It was found that the incidence of leaf mold, tomato spotted wilt virus, and tomato chlorosis virus disease was severe in tomato, and disease incidence of powdery mildew and zucchini yellow mosaic virus were severe in Cucurbit. The disease outbreak was found to be faster and more severe in crops grown in pesticide-free cultivation plastic greenhouses than in plastic greenhouses that are cultivated in general using pesticides. In particular, the occurrence of viral diseases mediated by thrips and aphids was found to be severely damaged. Therefore, in order to produce good organic products, it is important to effectively control pests, and in order to minimize the damage caused by disease, sanitation and physical blocking, and comprehensively utilize organic materials or microorganisms to prevent them.