• Research in Plant Disease
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• v.18 no.1
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• pp.1-9
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• 2012

A total of 20 agricultural organic materials including inorganic compounds, plant oils and plant extracts were used in the study for assessing the control efficacy on pepper diseases. Among inorganic compounds, only copper hydroxide showed inhibitory effect on both Phytophthora capsici causing Phytophthora blight and Colletotrichum acutatum causing anthracnose. Phosphorous acid inhibited the growth of P. capsici on PDA, and Sulfur/quicklime had it on that of C. acutatum. Plant essential oil, rosemary oil, and rapeseed oil among plant oils and plant extract of Japanese apricot/ginkgo nut inhibited the mycelial growth of the two pathogens. In the screening using pepper plant seedlings, the control efficacy on Phytophthora blight in 6-leaf stage of seedling was superior to that in 4-leaf stage of seedling. A protective effect on Phytophthora blight was displayed by copper hydroxide, sulfur/quicklime, water soluble calcium, phosphorous acid, plant essential oil, and cloves extract. When C. acutatum was inoculated by the non-wound method, copper hydroxide and rapeseed oil showed excellent protective activities with control values of 91.3% and 82.6%, respectively. However, copper hydroxide did not show any activity, when C. acutatum was inoculated after wounding pepper fruits. All organic materials never showed the curative effect on Phytophthora blight and anthracnose in pepper seedling assay and fruit assay.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.47-52
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• 1995

One hundred and thirty bacterial isolates with high chitinolytic activity on chitin agar media were isolated and identified. Most of the isolates were Aeromonas hydrophila (110 isolates), and the others were Serratia marcescens (11 isolates), Aeromonas caviae (3 isolates), Chromobacterium violaceum strain C-61 (2 isolates), Chromobacterium violaceum strain C-72 (1 isolate) and unknown species (3 isolates). Among them, C. violaceum strain C-61 had highest chitinolytic activity and fungal growth inhibition on PDA. This bacterium also inhibited the growth of Rhizoctonia solani, Sclerotinia scelrotiorum, Phytophthora capsici and Pythium ultimum, but it didn't inhibit the growth of Fusarium oxysprum and Fusarium solani. C. violaceum strain C-61 suppressed damping-off of eggplant caused by R. solani. Populations of the chitinolytic bacteria such as Aeromonas hydrophila, Serratia marcescens, Aeromonas caviae, Chromobacterium violaceum strain C-61 and Chromobacterium violaceum strain C-72 introduced into R. solani-infested soil were continuously decreased until 20 days after treatment, but their populations except A. caviae were not changed significantly and maintained over 5$\times$104 CFU per g of soil thereafter.

• Research in Plant Disease
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• v.17 no.2
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• pp.148-154
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• 2011

This study was conducted to control the seed borne pathogens (Alternaria spp.) of carrot and to examine the seed germination rate by using 13 environment friendly agricultural materials instead of conventional chemicals for organic cultivation. The growth inhibiting effects on pathogens showed the different responses according to each agricultural material and effective 7 materials against seed borne pathogens were selected. Among 7 materials, the carrot seeds sterilized with plant extracts, Tanger Stop and Land Saver were not germinated at all. The germination rate of seeds sterilized with other materials showed the similar levels with reference chemical (Benlate-T) and non-treated seeds. Infection rates of seeds sterilized with seaweed extract, Bellopper for controlling A. radicina and plant extract, Ssial-100 for A. dauci were similar or low infection rate compared with reference chemical. The germination rate and root length of seeds sterilized with Bellopper and Ssial-100 was similar or superior to those of chemical sterilized seeds. The optimal condition seemed to be a little bit different depending on the concentration of materials. As a result, the sterilization of carrot seeds by using the environment friendly materials could be effectively utilized as a technology to inhibit the infection of seed-borne pathogens.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.138-143
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• 2008

Botrytis cinerea, gray mold pathogen, causes serious losses in greenhouse tomato crop. In this study, a primer set was developed for identification and specific PCR detection of B. cinerea from tomato plants. The primer pair (BTF1/BTR1) was designed from polymorphic sequence region in pyruvate carboxylase gene (pyc) of B. cinerea. A PCR product (112 bp) was amplified on genomic DNA of 13 B. cinerea isolates from 10 different host plants, but not on those from 6 other Botrytis spp., 4 Botryotinia spp., 5 Sclerotinia spp. and 16 other genus of phytopathogenic fungi. The sensitivity limit of the primer set was 2 pg of genomic DNA of B. cinerea, approximately. The PCR assay using species-specific primer set was specifically able to detect the pathogen on naturally infected tomato plants and artificially infected plants. These results suggest that the sensitivity and specificity of this primer set can be applied in a rapid and accurate diagnosis of tomato disease caused by B. cinerea.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.295-310
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• 2017

This study investigated the growth of five phytopathogenic fungi including Colletotrichum gloeosporioides, Diaporthe citri, Phytophthora capsici and others according to different concentrations of water extract in order to provide reference data for developing environment-friendly agricultural materials using five native Fagaceae species including Quercus acuta, Quercus salicina, Quercus glauca, Quercus gilva and Castanopsis cuspidata var. sieboldii. As the concentration of aqueous extracts of Fagaceae increased according to donor plants, the mycelial growth of phytopathogens showed a decreasing tendency. Differences were found in the degree of inhibition according to types of donor plants and pathogenic fungi. Diaporthe citri, Phytophthora capsici, Pythium graminicola on the water extract of Castanopsis cuspidata var. sieboldii inhibited mycelial growth by 84% in 25% of the treatment group and by 87% in more than half of the treatment group. The water extract of Quercus acuta was found to have no inhibitory effect against the mycelial growth of Diaporthe citri. The aqueous extracts of Quercus salicina, Quercus glauca and Quercus gilva insignificantly inhibited mycelial growth by approximately 15%. The total phenolic content of receptor plants exhibiting antifungal activity was highest in Castanopsis cuspidata var. sieboldii with a content of 22.32 mg/g phenols, followed by Quercus salicina with 8.32 mg/g, Quercus glauca with 6.83 mg/g, Quercus gilva with 5.95 mg/g, and Quercus acuta with 5.24 mg/g. The aqueous extracts of Castanopsis cuspidata var. sieboldii among the five Five Fagaceae Plants of were the most effective antifungal activity.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.10 no.3 s.90
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• pp.82-89
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• 1989

포도는 생육기간중 뿐만 아니라 수확후 저장, 수송중에도 많은 종류의 병에 의하여 피해를 받아 수확량이 감소되고 품질이 저하된다. 각종 병에 의한 수확량 감소는 해마다 차이가 있으나 외국의 경우 일반적으로 약 $5\%$정도의 수확량이 감소되는 것으로 추측되고 있고 기상환경이 적합하여 병이 대발생할 경우에는 수확량이 $20\~80\%$ 감소된다는 보고도 있다. 이러한 심각한 손실을 일으키는 병들의 병원균은 크게 곰팡이, 세균, 바이러스, 선충으로 구분될 수 있는데 지역에 따라 존재하는 병원균의 종류, 재배품종들의 각종 병에 대한 감수성 정도, 그리고 기상환경에 따라 각 포도원에서 발생되는 병의 종류와 병 발생량에 차이가 있다. 우리나라에서 발생되는 포도병은 18종이 기록되어 있는데 여기서는 곰팡이에 의한 병인 흰가루병, 노균병, 탄저병, 흑두병, 잿빛곰팡이병의 발생생태와 방제법에 관하여 알아본다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.13 no.4 s.109
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• pp.44-50
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• 1992

핵과류는 7$\cdot$8월에 신선한 생과실을 제공해 줄 뿐만 아니라 가공품으로서 년중 공급되는 중요 과실이다. 우리나라의 핵과류 재배면적은 17,000여ha로 사과 밀감 다음으로 크며, 과수전체 면적의 15$\%$를 차지하고 있는 실정으로 생산량은 약 20만 톤에 이른다(원시, 1987). 또 핵과류는 통조림 주스 등으로 11,700톤이 생산되는데 전체 과실통조림과 넥타의 32$\%$를 충당하고 있다. 복숭아 및 기타 핵과류에 발생하는 병의 종류는 모두 24종이 알려져 있으나 병원균의 종류에 따라서는 중복해서 기생하는 것이 있으므로 17종의 병원균에 의해서 병이 발생된다(한식보, 1986). 그 동안 복숭아의 재배방법 중 크게 바뀌고 있는 것은 무대재배(無袋栽培) 및 시설재배 면적의 증가와 재배품종의 변화 등을 들 수 있다. 무대재배로 인해서 발생이 증가되는 것은 세균성구멍병, 검은점무늬병, 잿빛무늬병 및 탄저병 등으로 품질저하 현상으로 나타난다. 시설재배와 관련되는 것은 흰가루병과 잿빛곰팡이병이다.

• The Korean Journal of Mycology
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• v.11 no.1
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• pp.33-34
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• 1983

흰가루병(病)에 감염(感染)된 괭이밥(Oxalis corniculata L.)을 1982년(年) 6월(月) 수원(水原)에서 다수(多數) 채집(採集)하였다. 병원균(病原菌)의 형태적(形態的) 특징(特徵)을 검경(檢鏡)한 결과(結果), 한국산(韓國産) 미기록(未記錄) 흰가루병균(病菌)인 Oidium oxalidis McAlp.로 동정(同定)되었다. 이병식물(罹病植物)은 10월말경(月末頃) 거의 고사(枯死)하였으며, 이 병원균(病原菌)의 완전세대(完全世代)는 관찰(觀察)되지 않았다.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.110-117
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• 2009

To characterize plant root-associated bacteria in wild plant family Solanaceae, Solanum nigrum L. plants were collected in Dokdo island. Forty four strains of nitrogen-fixing or spore-forming bacteria were isolated from rhizosphere of Solanum nigrum L. plants. Among these, 19 strains were able to produce auxin. Thirteen strains of these produced siderophore as determined by color reaction on CAS-blue plate, 8 strains were able to solubilize phosphate. The 16S rDNA genes of the isolated bacteria were amplified and sequenced. Model plants, pepper and tobacco, were established in order to evaluate the bacterial capacities eliciting growth promotion and induced systemic resistance. The plants treated with strain KUDC1009 were more resistant and capable of growth-promotion than control plants when challenged by either Xanthomonas axonopodis pv. vesicatoria or Erwinia carotovora sub. carotovora strain SCC1. Rhizobacteria isolated from Dokdo island can promote growth of wild type Solanum nigrum L. under much environmental stresses.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.9-14
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• 2001

Colletotrichum species are important fungal pathogens that cause great damages on various host plant species worldwide. In Korea, Colletotrichum species cause massive economic losses on apple, peach, grape, and especially, sweet persimon productions. In the past, identification of the pathogen and the studies on the genetic relationships among the pathogenic isolates were mainly based on morphology, cultural characteristics, and the difference in pathogenicity. However, in recent years, these traditional methods have been replaced with molecular methods including AFLP. AFLP method with the merits of both RAPD and RFLP has been widely used for the genetic relationship studies of various organisms. Therefore, in this study, AFLP method was employed for the studies of genetic relationships among the different isolates of Colletotrichum species collected from various parts of sothern Korea. As a result, two specific band pattern groups were observed among different isolates of Colletotrichum species.