• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.193-199
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• 2013

Burkholderia pyrrocinia CAB08106-4 has an anti-bacterial effect on Garlic White Rot caused by Sclereotium cepivorum and Sclereotium sp.. It is an environmentally friendly microbial product that prevents and controls a variety of phytopathogens involving Garlic White Rot caused by Sclereotium cepivorum and Sclereotium sp.. The aim of this study was to assess and to compare the pathogenicity of Burkholderia pyrrocinia CAB08106-4 by single exposure of rats through several routes such as oral, intranasal and intravenous. For the acute toxicity / pathogenicity study, the animals were sacrificed on days 3, 7, 14 and 21, and macroscopically observed their organs to examine the numbers of internally-retained pesticidal microbes. Clinical examinations were performed daily during administration period, and body weight gain was evaluated. In the study, no clinical sign, weight gain and mortality were observed in relation to the administration of test article. The significant changes of internal/external microbes by test article were not detected. The pathological findings in relation to the administration of the test article in the necropsy were not observed. It could be concluded that the microorganism was not toxic or pathogenic in rats via oral, intranasal and intravenous route.

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.133-139
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• 2013

To investigate the sensitivity of Sclerotium cepivorum causing garlic white rot to 5 fungicides, including prochloraz, tebuconazole, flutolanil, iminoctadine and isoprothiolane, 147 isolates isolated from infected garlics from 2008 to 2009 through a single sclerotium isolation were screened. While each mean value of $EC_{50}$ (effective concentration reducing mycelial growth by 50%) of S. cepivorum isolates collected in 2008 to each fungicide was 0.054, 0.012, 23.189, 0.901, and $21.362{\mu}g\;mL^{-1}$, that of 2009 isolates were 0.030, 0.020, 10.367, 1.684, $33.406{\mu}g\;mL^{-1}$. There was a difference in mean value of $EC_{50}$ of S. cepivorum according to regions isolated. $EC_{50}$ values of S. cepivorum isolated in Goheung to flutolanil and isoprothiolane were 14.468 and $24.653{\mu}g\;mL^{-1}$, respectively, which was lower than those of Seosan and Taeahn. Isolates from Taeahn showed the lowest $EC_{50}$ value to prochloraz as $0.008{\mu}g\;mL^{-1}$. In addition, we could not find any resistant isolates to fungicides tested. The $EC_{50}$ values in this study will be used in a fungicide resistance monitoring program to determine whether shifts in sensitivity to fungicides included into different groups are occurring in S. cepivorum populations.

• Research in Plant Disease
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• v.12 no.3
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• pp.254-259
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• 2006

Bacillus spp. isolated from mushroom medium wastes were evaluated for their biocontrol potentials on control of Sclerotinia rot of lettuce. The Bacillus isolates were more effectively obtained from waste suspension when directly added into nutrient agar(NA) medium than plating on the agar medium. Totally 42 isolates obtained from the wastes B23 and B42 showed highest antifungal activity against eight fungal pathogens such as Sclerotinia sclerotiorum, Rhizoctonia solani, Pythium ultimum, Phytophthora capsici, Fusarium oxysporum, Colletotrichum gloeosporioides, Cladosporium cucumerinum, and Botrytis cinerea and B23 and B42 were finally selected for further studies. Optimal concentration of the isolates was $10ml(10^7cfu/ml)$ to suppress the Sclerotinia rot of lettuce. Supplements such as starch, glycerol, and egg-yolk successfully maintained the bacterial population for 30 days in vitro and increased bio-control potentials against the disease. The bacterial isolate B23 alone showed 72% control value, furthermore it presented 95% control value when supplemented with 0.2% of starch, glycerol, and egg-yolk. The promising Bacillus isolates B23 and B42 were identified as Brevibacillus brevis and Bacillus stearothermophillus, respectively, based on morphological and physiological characteristics according to API database.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.198-205
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• 1999

Cucurbitaceous vegetable crops grown in greenhouses in Korea were surveyed from 1995 to 1997. Incidence of Sclerotinia rot was as high as $30{\sim}70%$ at its maximum on Cucumis melo var. reticulatus (netted melon), Cucumis sativus (cucumber), Cucurbita moschata (pumpkin) and Cucurbita pepo (summer squash) but relatively low on Citrullus lanatus (watermelon) and Cucumis melo var. makuwa (oriental melon). Symptoms of Sclerotinia rot developed on stems of all the cucurbits, fruits of five cucurbits except C. lanatus, petioles of two Cucurbita spp. and leaves of C. moschata. A total of 126 isolates of Sclerotinia sp. were obtained from the lesions and identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The fungus was very frequently isolated from stems and fruits of the cucurbits but rarely from petioles and leaves. Six isolates of the fungus were pathogenic to six cucurbits tested although there was some difference in virulence among the isolates to some of the hosts. C. lanatus was the most susceptible to the isolates, whereas C. melo var. makuwa was the most resistant. C. melo var. reticulatus and C. sativus were relatively susceptible to the isolates, and C. moschata and C. pepo relatively resistant.

• Research in Plant Disease
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• v.23 no.1
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• pp.56-59
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• 2017

During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia ($30-100{\mu}m$ diameter) formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and $5-50{\mu}m$ diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.69-75
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• 2012

In response of fungicides for control of gray snow mold, isolates of Typhula incarnata were collected from three golf courses in 2012 Yongpyeong, Korea and tested for sensitivity to propiconazole, tebuconazole and azoxystrobin fungicides. Four discriminatory concentrations were used to detect in vitro sensitivity of 50 isolates. Mean 50% effective concentration inhibiting mycelial growth ($EC_{50}$) values for tebuconazole was the lowest among the three fungicides. The $EC_{50}$ value of tebuconazole ranged from 0.0005 ${\mu}g\;ml^{-1}$ to 0.014 ${\mu}g\;ml^{-1}$ with a mean of 0.0048 ${\mu}g\;ml^{-1}$. The mean $EC_{50}$ values of propiconazole in triazole family was 0.5825 (0.78-1.651) ${\mu}g\;ml^{-1}$. $EC_{50}$ value of azoxystrobin ranged from 0.0017 ${\mu}g\;ml^{-1}$ to 0.131 ${\mu}g\;ml^{-1}$ with a mean of 0.0278 ${\mu}g\;ml^{-1}$. There was no correlation among $EC_{50}$ values for propiconazole, azoxystrobin and tebuconazole indicating no cross-resistance relationships with each other. Results of this study were confirmed no resistance isolates in vitro sensitivity of T. incarnata of three fungicides in Yongpyeong.

• Journal of Climate Change Research
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• v.5 no.1
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• pp.47-59
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• 2014

This study was conducted to estimate of future productivity for major spicy vegetables by the change of meteorological factors, temperature and precipitation. Based on analysis of meteorological factors, incidence of major disease(phytophthora blight and anthracnose) for hot pepper was over 50% with temperature over $18.3^{\circ}C$ in May and precipitation over 532 mm in July. And the meteorological factors in the August have deeply related to the incidence of virus disease(CMV and BBWV2) for hot pepper, however, both the meteorological factors and the incidence of virus disease showed to the opposite tendency. An analysis of the relevance of the white rot disease and the meteorological factors for garlic, a disease was highly investigated with temperature $15.0^{\circ}C$ to $15.9^{\circ}C$ in April to May. On the onion, higher incidence of white rot was investigated with temperature over $4.0^{\circ}C$ in November to January and precipitation over 40 mm in March. The occurrence of major disease for spicy vegetables and meteorological factors as a result of regression analysis, the optimal cultivation area of peppers and onions will be gradually expanded to the central regions in the near future in Korea.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.9 no.3
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• pp.38-48
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• 1988

고추$\cdot$참깨등 경제작물에 발생하는 병해는 수십여종이 있으나 그중 국내에서 흔히 발생하며 피해가 큰 병해는 곰팡이병으로 노균병, 잿빛곰팡이병, 탄저병, 균핵병, 시들음병, 역병 등 6종, 세균병으로는 무름병, 풋마름병, 세균성점무늬병등 3종, 그리고 바이러스에 의한 병을 들수 있다. 이 병해들은 그 종류별로 병징, 병발생 양상, 전염방법 등에 특징이 있기 때문에 기생하고 있는 작물이 다를지라도 병의 구별이 가능하고 동일종류에서는 병의 방제방법도 비슷하다. 최근 문제되고 있는 병해를 중심으로 진단법과 방제법을 알아본다.

• THE HEALTH and ORGANIC FARMING
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• no.185
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• pp.1-24
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• 2002

한국유기농업대회 성황리 개최/제24회한국유기농업대회 대회사/'남성증명서'가 필수 혼수품이 되다니./제24회한국유기농업대회 이모저모/유전자 변형작물 유해 논란속 확산 가속/"쌀소득보전기금" 제정추진/유럽의 어메니티 정책동향/환경개선으로 병해충을 막아보자/친환경농업 양파.마늘 재배기술/12월중 농사정보/당신도 무병장수를 꿈꾸는가?/딸기의주요병해와 친환경적 방제기술/쌀도 브랜드시대/콩 가공식품 인기절정/엽채류 균핵병 방제/유기농업경영의 삼장 통합구상

• The Korean Journal of Mycology
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• v.10 no.2
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• pp.93-94
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• 1982

Soybean Whetzelinia rot caused by Whetzelinia sclerotiorum was observed in Jinju area. The diseased soybean plants showed withering and sudden collapse under field conditions. Diseased parts exhibited numerous black, irregularly-shaped scleratia embedded in dense white cottonly mycelium on tissue and in the pith of diseased stems. A sclerotium in the moist sand produced several apothecia under laboratary condition. The primary inoculum was supposed to originate from overwintered sclerotia of soil and soybean debris.