• 제목/요약/키워드: black spot

검색결과 186건 처리시간 0.026초

An investigation of Panax ginseng Meyer growth promotion and the biocontrol potential of antagonistic bacteria against ginseng black spot

  • Sun, Zhuo;Yang, Limin;Zhang, Lianxue;Han, Mei
    • Journal of Ginseng Research
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    • 제42권3호
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    • pp.304-311
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    • 2018
  • Background: Ginseng black spot disease resulting from Alternaria panax Whuetz is a common soil-borne disease, with an annual incidence rate higher than 20-30%. In this study, the bacterial strains with good antagonistic effect against A. panax are screened. Methods: A total of 285 bacterial strains isolated from ginseng rhizosphere soils were screened using the Kirby-Bauer disk diffusion method and the Oxford cup plate assay. We analyzed the antifungal spectrum of SZ-22 by confronting incubation. To evaluate the efficacy of biocontrol against ginseng black spot and for growth promotion by SZ-22, we performed pot experiments in a plastic greenhouse. Taxonomic position of SZ-22 was identified using morphology, physiological, and biochemical characteristics, 16S ribosomal DNA, and gyrB sequences. Results: SZ-22 (which was identified as Brevundimonas terrae) showed the strongest inhibition rate against A. panax, which showed 83.70% inhibition, and it also provided broad-spectrum antifungal effects. The inhibition efficacies of the SZ-22 bacterial suspension against ginseng black spot reached 82.47% inhibition, which is significantly higher than that of the 25% suspension concentrate azoxystrobin fungicide treatment (p < 0.05). Moreover, the SZ-22 bacterial suspension also caused ginseng plant growth promotion as well as root enhancement. Conclusion: Although the results of the outdoor pot-culture method were influenced by the pathogen inoculum density, the cropping history of the field site, and the weather conditions, B. terrae SZ-22 controlled ginseng black spot and promoted ginseng growth successfully. This study provides resource for the biocontrol of ginseng black spot.

Alternaria alternata에 의한 단감 검은점무늬병 발생 (Black Spot of Sweet Persimmon (Diospyros kaki) Caused by Alternaria alternata)

  • 권진혁;안광환;박창석
    • 식물병연구
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    • 제10권3호
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    • pp.183-187
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    • 2004
  • 2002년 경남 창원시 동읍 단감 저온 저장고에 저장중인 과실에서 검은점무의 증상이 심하게 발생하였다. 병징은 과실표면에 검은색 둥근 반점이 생기고 병반부위가 확대되면서 그 위에 암갈색의 곰팡이를 형성한다. 병반부위를 절단해 보면 감염된 표피에서부터 시작하여 과육내부까지 갈색으로 변색되고 스폰지 모양으로 부패되어 상품성이 전혀 없다. 병원균의 분생포자는 난형, 곤봉형, 서양배형이고 드물게 타원형도 있으며 횡격막이 3∼5개, 종격막이 1∼2개 있다. 색깔은 연한 갈색 또는 금색을 띄는 갈색이고 크기는 12∼46${\times}$6∼12$\mu\textrm{m}$이었다. 분생포자경은 연한 담갈색이고, 크기는 42∼95${\times}$3∼5 $\mu\textrm{m}$이었다. 균사생육적온은 25∼3$0^{\circ}C$이었다. 단감 저장중 과실에 발생한 병징과 병원균의 균학적 특징을 조사한 결과, 이 병을 Alternaria alternata (Fr.) Keissler에 의한 단감 검은점무의병으로 명명하고자 제안한다.

First Report of Leaf Spot Caused by Alternaria tenuissima on Black Chokeberry (Aronia melanocarpa) in Korea

  • Wee, Jung-In;Park, Jong-Han;Back, Chang-Gi;You, Young-Hyun;Chang, Taehyun
    • Mycobiology
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    • 제44권3호
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    • pp.187-190
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    • 2016
  • In July 2015, diseased leaves of black chokeberry (Aronia melanocarpa) were observed in Danyang and Gochang, Korea. The symptoms appeared as circular or irregular brown leaf spots, from which Alternaria tenuissima was isolated. The isolates were cultured on potato dextrose agar, and their morphological characteristics were observed under a light microscope. The colonies were whitish to ash colored. The pathogenicity test on healthy black chokeberry leaves produced circular brown spots, in line with the original symptoms. Molecular analyses of the ITS, GPD, RPB2, and TEF genes were conducted to confirm the identity of the pathogen. The phylogeny of the multi-gene sequences indicated that the causal agent was A. tenuissima. This study is the first report of A. tenuissima leaf spot on black chokeberry (A. melanocarpa).

Fusarium moniliforme에 의한 덴파레 검은점무늬병 (Black Leaf Spot of Dendrobium phalaenopsis Caused by Fusarium moniliforme)

  • 이동현;허재선;고영진
    • 식물병연구
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    • 제9권3호
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    • pp.149-152
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    • 2003
  • 전남 광양읍 봉강면의 양란 재배농가에서 재배되고 있는 덴파레에 검은점무늬병이 발생하였다. 자연 발병한 덴파레의 잎에는 초기에 검은색의 작은 점무늬가 형성되어 점차 진전되면서 잎 전체가 누렇게 변하면서 고사해 버리며 소엽병의 마디가 약화되어 낙엽이 지고 심하면 식물체 전체가 말라죽었다. 검은점무늬병에 감염된 덴파레의 병환부로부터 분리된 병원균은 감자한천배지 상에서 초기에 흰색을 띠며, 점차 시간이 지남에 따라 진한 보라색을 띠었으며, 균사생장 적온은 $25^{\circ}C$였다. 덴파레 잎의 검은 점무늬 병반으로부터 분리한 병원균은 균학적 특성 및 병원성 검정 결과 Fusarium moniliforme로 동정되었다. 병원균은 상처 접종에 의해서만 덴파레에 병원성을 나타내었고, 호접란과 심비디움에 대해서도 모두 병원성을 나타내었다. 따라서 이 병을 Fusarium moniliforme에 의한 덴파레 검은점무늬병으로 명명할 것을 제안한다.

First Report of Black Spot Disease Caused by Alternaria alternata on Sweet Persimmon Fruits

  • Lee, Jung Han;Kim, Jinwoo;Kwak, Youn-Sig
    • Mycobiology
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    • 제41권3호
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    • pp.167-169
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    • 2013
  • Black spot of sweet persimmon, caused by Alternaria alternata, occurred in an orchard in Gyeongnam province, Korea in 2012. The symptom was appearance of 0.5 to 4 cm black spots on the surface of fruit. The pathogen was isolated from flesh of disease lesions. The causal agent was identified as A. alternata by morphological characteristics and sequencers of the internal transcribed spacer (ITS) 1 and ITS4 regions of rRNA. Artificial inoculation of the pathogen resulted in development of disease symptoms and the re-isolated pathogen showed characteristics of A. alternata.

일본 냉동새우 선물시장의 가격발견기능에 관한 연구 (A Study on Price Discovery Function of Japan's Frozen Shrimp Future Market)

  • 남수현
    • 수산경영론집
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    • 제37권1호
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    • pp.95-110
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    • 2006
  • Japan's frozen shrimp future market is the only fisheries future commodity market in the world. This empirical study examines the lead and lag relationship between Japan frozen shrimp spot and future markets using the daily prices from August 1, 2002 to December 31, 2005. Frozen shrimp future contract is listed on Japan Kansai Commodities Exchange. Japan imports approximately 250,000 tons of frozen shrimp annually, of which just under 70,000 tons, nearly 30%, are black tiger shrimp. Approximately 90% of black tiger shrimp are caught in Indonesia, India, Thailand and Vietnam, and the two largest consumers of these shrimp are Japan and the U.S.A. Kansai Commodities Exchange adopts the India black tiger shrimp as standard future commodity. We use unit root test, Johansen cointegration test, Granger causality test, Vector autoregressive analysis and Impulse response analysis. However, considering the long - term relationships between the level variables of frozen shrimp spot and futures, we introduced Vector Error Correction Model. We find that the price change of frozen shrimp futures with next 1, 2, 3, 4, 5 month maturity have a strong predictive power to the change of frozen shrimp spot and the change of frozen shrimp spot also have a predictive power to the change of frozen shrimp with next 1, 2, 3 month maturity. But, the explanatory power of the frozen shrimp futures is relatively greater than that of frozen shrimp spot.

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교통사고잦은곳 발생분포를 활용한 개선사업 구간선정 방안 (Identification Method for Hazardous Road Sections Based on Black Spot Distribution)

  • 김상옥;안성채;최기주;장일준
    • 대한교통학회지
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    • 제26권3호
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    • pp.67-74
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    • 2008
  • 현재 시행 중인 지점단위 사고잦은곳 개선사업은 매년 효율성이 저하되고 있으나, 효율성 제고방안으로 제기되고 있는 구간단위 개선사업은 방법론에 있어 아직까지 구체적인 방안이 제시되지 못하고 있는 실정이다. 이에 본 연구는 일반국도를 대상으로 개선사업 및 미개선사업 지점으로 부터 사업 차년도 신규 사고잦은곳에 이르는 거리자료를 분석하여, 적정 개선사업 구간길이 및 구간설정 방안을 제시하고자 하였다. 거리자료 분석결과, 개선사업을 실시한 교차로로부터 2Km 내 신규 사고잦은곳이 발생할 확률이 미개선 교차로 지점에 비해 높은 것으로 나타났으나 개선사업 내역별 거리분포 차이는 미미한 것으로 나타났다. 최종적으로, 상호 인접거리가 2km내에 있는 일련의 사고잦은곳을 포함하는 구간을 개선사업 후보구간으로 선정하는 방안을 제시하였다.

Comparison of Live Performance and Meat Quality Parameter of Cross Bred (Korean Native Black Pig and Landrace) Pigs with Different Coat Colors

  • Hur, S.J.;Jeong, T.C.;Kim, G.D.;Jeong, J.Y.;Cho, I.C.;Lim, H.T.;Kim, B.W.;Joo, S.T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권7호
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    • pp.1047-1053
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    • 2013
  • Five hundred and forty crossbred (Korean native black pig${\times}$Landrace) F2 were selected at a commercial pig farm and then divided into six different coat color groups: (A: Black, B: White, C: Red, D: White spot in black, E: Black spot in white, F: Black spot in red). Birth weight, 21st d weight, 140th d weight and carcass weight varied among the different coat color groups. D group (white spot in black coat) showed a significantly higher body weight at each weigh (birth weight, 140th d weight and carcass weight) than did the other groups, whereas the C group (red coat color) showed a significantly lower body weight at finishing stage (140th d weight and carcass weight) compared to other groups. Meat quality characteristics, shear force, cooking loss and meat color were not significantly different among the different coat color groups, whereas drip loss was significantly higher in F than in other groups. Most blood characteristics were not significantly different among the different groups, except for the red blood cells.

배나무 검은무늬병균(Alternaria kikuchiana Tanaka)에 병원성분화와 저항성품종의 이병화 (Differentiation in Pathogenicity of Alternaria kikuchiana Tanaka, Black Spot Fungus of Pear, and Conversion of Resistant Varieties into Susceptible ones)

  • 기운계;박서기;조백호;김기청
    • 한국응용곤충학회지
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    • 제23권1호
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    • pp.7-14
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    • 1984
  • 전남 나주지방에서 만연하고 있는 검은무늬 병 유사증상을 조사한 결과는 다음과 같다. 1. 병원균은 Alternaria kikuchiana Tanaka로 동정되었다. 2. 5월 하순부터 발병되기 시작하여 6월 하순$\~$7월상순에 가장 심하였고 9월 상순에 다시 증가하였다. 3. 이병은 조사품종들의 성엽에 발생하였으나 20세기에서만 유엽에 많이 발생하였다. 5. 이 병은 나주시험장에 있는 거의 모든 품종에 발병하였는데 종래 저항성품종으로 알려진 신흥, 만3길등은 가장 심한 발병을 보였고 이병성품종으로 알려진 조옥, 박다청등은 약간 발병하거나, 전혀 발병하지 않았다. 6. 이상의 결과로 미루어 보아 검은무늬병균에 병원성의 분화가 일어난 것으로 판단된다.

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Incidence Rates of Major Diseases of Kiwiberry in 2015 and 2016

  • Kim, Gyoung Hee;Kim, Deok Ryong;Park, Sook-Young;Lee, Young Sun;Jung, Jae Sung;Koh, Young Jin
    • The Plant Pathology Journal
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    • 제33권4호
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    • pp.434-439
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    • 2017
  • Incidence rates of diseases in kiwiberry orchards were investigated monthly from late June to late September in Gwangyang and Boseong in 2015 and 2016. The impact of postharvest fruit rot was investigated during ripening after harvest. Bacterial canker was only observed on one single tree in 2015, but black rot, powdery mildew, leaf spot and blight, and postharvest fruit rot diseases were problematic throughout the study period in both 2015 and 2016. Incidence rates of the diseases varied with kiwiberry cultivar, region and sampling time. Incidence rates of powdery mildew, leaf spot and blight diseases increased significantly during the late growing stages near fruit harvest, while black rot peaked in late August. Incidence rate of postharvest fruit rot on fruit without fruit stalks was less than half of fruit with fruit stalks, regardless of kiwiberry cultivars. Among the four cultivars, Mansu was relatively resistant to black rot and postharvest fruit rot diseases. In our knowledge, this is the first report of various potential pathogens of kiwiberry in Korea.