• 제목/요약/키워드: Spore germination inhibition

검색결과 66건 처리시간 0.03초

Acetic acid에 의한 저온저장고 내의 균발생 억제 효과 (Inhibition of Incidence of Fungi in Cold Storage Room by Acetic Acid)

  • 임병선;윤해근;정석태;최선태
    • 원예과학기술지
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    • 제19권2호
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    • pp.170-173
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    • 2001
  • Acetic acid는 상온($25^{\circ}C$)에서 저온저장고에 발생하는 과실의 부패병균인 Botrytis cinerea 및 Penicillium expansum의 포자발아 및 발아관 생장 억제에 효과가 나타났다. $4.8mg{\cdot}L^{-1}$의 acetic acid 함유배지에서는 처리 12시간 후에도 B. cinerea 및 P. expansum의 포자가 전혀 발아하지 않았으며, 처리 7일 후에도 거의 생장하지 못할 정도로 완전한 균사생장 억제효과를 나타내었다. 저온($2^{\circ}C$)에서도 B. cinerea 및 P. expansum에 대해 acetic acid의 농도가 높을수록 균사생장 억제효과가 증가하였으며 $4.8mg{\cdot}L^{-1}$를 함유한 배지(PDA)에서는 처리한 후 20일이 경과하여도 균총이 전혀 형성되지 않았다. 저온저장고를 가동하기 전에 기존의 $SO_2(5g{\cdot}m^{-3})$ 가스와 acetic acid($4.8g{\cdot}m^{-3}$)를 처리한 저장고에서 출현하는 균의 발생을 감소시켰다. 그러나 실제 적용시 인체에 대한 자극성이 있다는 점에 대한 보완책이 필요할 것으로 생각되었다.

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여러 종류의 in vitro 생물검정에서 Botrytis cinerea에 대한 sulphamide계와 dicarboximide계 살균제의 활성 특성 (Antifungal activities of sulphamide and dicarboximide fungicides against Botrytis cinerea in several in vitro bioassays)

  • 최경자;김흥태;김진철;조광연
    • 농약과학회지
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    • 제3권3호
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    • pp.37-44
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    • 1999
  • In vivo와 in vitro 생물검정법에서의 활성관계를 조사하고 또한 보다 효율적인 in vitro 검정법을 개발하기 위하여 작용기구가 다른 두 계열 살균제 즉 sulphamide계 (dichlofluanid와 tolylfluanid)와 dicarboximide계 살균제 (iprodione, vinclozolin 및 procymidone)을 시험약제로 하여 본 실험을 수행하였다. Dichlofluanid, tolylfluanid, iprodione, vinclozolin procymidone의 토마토 유묘에서의 병 방제효과는 유사하였다. 그러나 이들 살균제에 대해 in vitro 생물검정법으로 항균활성을 비교한 결과, sulphamide계 살균제는 포자발아 억제실험에서 높은 활성을 나타낸 반면에, dicarboximide계 살균제는 균사생장 억제실험에서 항균활성이 더 우수하였다. 그러므로 in vivo 병 방제효과가 유사하더라도 작용기구가 다르면 in vitro 생물검정법에서의 항균활성은 다르게 나타남을 알 수 있었다. 또한 포자현탁액을 넣은 96-well microtiter plate에 약제를 처리하고 3시간 배양 후 배양액을 제거하고 다시 새 배지를 넣어 배양한 후 생장억제를 조사한 실험 (microtiter plate method I, MPM I)에서는 살균제들의 포자발아 억제실험과 유사한 경향의 활성을 보였다. 96-well microtiter plate에서 포자현탁액을 6시간 동안 배양하여 포자를 발아시킨 후에 약제를 처리한 실험(microtiter plate method II, MPM II)에서의 항균활성은 균사생장 억제효과와 일치하는 경향을 보였다. 따라서 기존의 in vitro 항균활성 실험보다 편리하고 효율적인 MPM I과 II 방법은 각각 포자발아와 균사생장 억제실험을 대신할 수 있으리라 생각되었다.

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Evaluation of Bio-Control Efficacy of Trichoderma Strains against Alternaria alternata Causing Leaf Blight of Ashwagandha [Withania somnifera (L.) Dunal]

  • Rahman, Md. Ahsanur;Rahman, Md. Arifur;Moni, Zakiah Rahman;Rahman, Mohammad Anisur
    • Journal of Forest and Environmental Science
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    • 제36권3호
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    • pp.207-218
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    • 2020
  • Ashwagandha is an important ancient medicinal crops, being affected with many diseases, among which leaf blight caused by Alternaria alternata has become the constraint resulting in huge yield losses. Continuous usage of chemical methods leads to environment, soil and water pollution. Whereas biological control of diseases is long lasting, inexpensive, eco-friendly and harmless to target organisms. In this context, it is aimed to evaluate five Trichoderma strains viz. Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433 and T. harzianum IMI-392434 as bio-control efficacy against A. alternata and growth promoting effect in Ashwagandha. All the Trichoderma strains had varied antagonistic effects against the pathogen. In dual culture technique, the strain T. harzianum IMI-392433 showed maximum percentage inhibition of mycelial growth (54.89%) followed by T. harzianum IMI-392432 (53.83%), T. harzianum IMI-392434 (48.94%) and T. virens IMI-392430, (43.62%) against the pathogen, while the least inhibition percentage was observed with the T. pseudokoningii IMI-392431 (36.60%). The culture filtrate of the Trichoderma strain, T. harzianum IMI-392433 recorded highest inhibition on the mycelial growth (39.05%) and spore germination (80.77%) of pathogen and the lowest was recorded in T. pseudokoningii IMI-392431 (20.45 and 50%). Moreover, seeds treated with spore suspension of the strain T. harzianum IMI-392433 reduced the percentages of disease severity index significantly. The strain T. harzianum IMI-392433 also significantly increased seed germination %, seedling vigor and growth of Ashwagandha. The correlation matrix showed that root yield per plant of Ashwagandha had significant and positive correlation with plant height (r=0.726⁎⁎), number of leaf (r=0.514⁎⁎), number of primary branch (r=0.820⁎⁎), number of secondary branch (r=0.829⁎⁎), fresh plant weight (r=0.887⁎⁎), plant dry weight (r=0.613⁎⁎), root length (r=0.824⁎⁎), root diameter (r=0.786⁎⁎), root dry weight (r=0.739⁎⁎) and fresh root weight (r=0.731⁎⁎). The significant and negative correlation (r=-0.336⁎⁎) was observed with the root yield and percentages of disease severity index. The study recognized that the T. harzianum IMI-392433 strain performed well in inhibiting the mycelial growth and reduced the percentages of disease severity index of pathogen as well as increased the plant growth in Ashwagandha.

Inhibitory Activity of Oak Pyroligneous Liquor against Coleosporium Plectranthi, an Obligate Parasite Responsible for the Rust Disease on Perilla Leaf

  • Kumar, Varun;Chauhan, Anil Kumar;Baek, Kwang-Hyun;Kang, Sun-Chul
    • 한국환경농학회지
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    • 제30권4호
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    • pp.453-458
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    • 2011
  • BACKGROUND: Coleosporium plectranthi, an obligate parasite, which is responsible for the rust disease of Perilla frutescens, a plant in Korea, commonly known as Perilla. All rusts are obligate parasites, meaning that they require a living host to complete their life cycle. They generally do not kill the host plant but can severely reduce growth and yield. Food and feed spoilage fungi cause great economic losses worldwide. It is estimated that between 5 and 10% of the world food production is wasted due to fungal deterioration. Rust disease of Perilla is highly frequent and is widely spread in Korea. The present study was designed to investigate a novel media for the urediniospore germination in vitro and anti-rust activity as well as GC-MS analysis of oak pyroligneous liquor. METHOD AND RESULTS: Urediniospores were collected from the infected leaf of Perilla. Spore suspension was made and the suspension was inoculated in the 2% water agar media with proper humidity, then they were incubated at $26^{\circ}C$ for 56 hrs. The GC-MS analysis of the oak pyroligneous liquor was also done to check the chemical composition. GC-MS analysis of the wood vinegar was found 15 compounds, among them o-mthoxyphenol (25.93%), 2,6-dimethoxyphenol (16.06%), 4-methylenecyclohexanone (10.69%), 2,3-dihydroxytoluene (7.84%), levoglucosane (6.14%) and propanoic acid (5.32%) were the major components. Different concentration of the oak pyroligneous liquor was used, and spore inhibition was recorded on the basis of spore counting. The best results were noted at the concentration of 50% solution where 31.8% spores were inhibited. CONCLUSION: On the basis of the chemical composition of the oak pyroligneous liquor and the activity recorded we can use it as an anti-rust agent.

Metarhizium anisopliae의 Fusarium oxysporum, Botrytis cinerea, Alternaria solani 등에 대한 항진균활성 (Antifungal Activities of Metarhizium anisopliae against Fusarium oxysporum, Botrytis cinerea, and Alternaria solani)

  • 강선철;박영구;이동규;김용헌
    • 한국균학회지
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    • 제24권1호통권76호
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    • pp.49-55
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    • 1996
  • 살충성진균 Metarhizium anisopliae가 시들음병을 일으키는 Fusarium oxysporum, 잿빛곰팡이 병을 일으키는 Botrytis cinerea, 겹둥근무늬병을 일으키는 Alternaria solani 등에 대하여 항진균활성을 갖는지 알아보았다. 그 결과 Plate상에서 균사생장저해 실험과 inhibition rate실험을 했을 때 항진균활성이 검정되었으며 또한 YPD배지에서 배양된 M. anisopliae로부터 얻은 배양여액을 식물병원균에 30%농도로 첨가했을 때 이들의 포자발아율은 B. cinerea, F. oxysporum에서 각각 21.5%(control: 88.2%), 53.0%(control: 78.6%)로 감소하였으며 발아개시 시간도 8시간 정도 지연되었다. 또한 현미경을 통한 미세구조관찰에서는 10% 배양여액을 첨가했을 때 F. oxysporum의 균사로부터 후막포자가 생성되고 생장저해가 일어나는 것이 확인되었다. 이상의 결과로부터 M. anisopliae의 항진균활성은 fungistatic effect를 나타냄을 알 수 있었다.

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고추 탄저병균에 대한 옻나무 추출물의 항진균 효과 (Antifungal Activity of Crude Extract Compound from Rhus verniciflua Against Anthracnose Fungi (Collectotrichum spp.) of Red-Pepper)

  • 송치현;정종배;정병룡;박세영;이용세
    • 한국환경농학회지
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    • 제31권1호
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    • pp.60-67
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    • 2012
  • 옻나무 주성분인 조추출액의 고추 탄저병균에 대한 항진균활성을 조사한 결과 1.0 mg urushiol/mL PDA 농도에서 18.3-39.5%의 억제효과가 있었으며, 푸른 고추에 병원성이 강한 것으로 조사된 GC계열의 균주보다는 DC계열의 균주에 대한 효과가 높았다. Urushiol의 농도가 1.0 mg/mL 일 경우 약 70% 정도의 포자가 발아한 PDB 용액에서보다 공시 모든 균주의 포자발아는 50% 이상 억제되었다. 동일한 농도에서 균사생장억제 효과 보다는 포자발아에 대한 억제 효과가 다소 높은 경향을 보였다. 푸른 고추와 붉은 고추에 옻 추출액을 처리하고 공시 탄저병균을 접종한 후 병 발생 억제효과를 in vitro에서 검정한 결과 붉은 고추에 DC 균주를 접종하였을 경우 1.0 mg/mL 농도 처리에서는 75.0%, 0.1 mg/mL 농도 처리에서는 58.0% 로 나타났으며, 푸른고추에 병원성이 강한 GC 균주를 접종하였을 경우에는 각각 68.1% 및 28.3% 탄저병 발생이 억제되었다. 비닐하우스에서 관행재배방법에 의해 고추를 재배하면서 고추 탄저병이 자연발생하기 시작한 8월 21부터 옻 추출액을 1주일 간격으로 3회 살포하고 최종 살포일 7일 후에 전체 고추 열매 중 이병 열매를 조사하여 옻 추출액의 병 발생 억제정도를 구한 결과 1차 조사한 9월 11일에는 무처리 대조구에 비해 옻 조 추출액을 1.0 mg/mL 처리한 시험구에서는 85.0% 탄저병 발생 억제효과를 보였으나, 0.01 mg/mL 처리구에서는 9.8%의 낮은 억제효과를 보였다. 9월 11일 조사 후 이병 열매를 모두 제거한 다음 동일한 방법으로 옻 추출액을 계속처리하고 10월 2일에 조사한 결과 1차 조사 시기보다 대조구의 이병과율이 훨씬 낮은 7.0% 였으며, 옻 추출액 처리효과는 공시 처리 농도별로 각각 60.0, 54.3 및 10.0%로 조사되었다.

Selection of KYC 3270, a Cellulolytic Myxobacteria of Sorangium cellulosum, against Several Phytopathogens and a Potential Biocontrol Agent against Gray Mold in Stored Fruit

  • Kim, Sung-Taek;Yun, Sung-Chul
    • The Plant Pathology Journal
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    • 제27권3호
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    • pp.257-265
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    • 2011
  • During 2002-2008 in Korea, 455 extracts from myxobacteria consisting of 318 cellulolytic and 137 bacteriolytic myxobacteria were isolated, which were then screened for antifungal activity against the phytopathogens Botrytis cinerea, Colletotrichum acutatum, Penicillium sp., Pyricularia grisea, and Phytophthora capsici. 204 isolates had antifungal activity, causing both a clear zone due to blocked spore germination and inhibition of mycelial growth; most (199) were from cellulolytic (Sorangium cellulosum) and only five were from bacteriolytic myxobacteria. B. cinerea, the best controlled among the five tested pathogens, had a unique group of antifungal isolates of myxobacterial extracts compared to the other pathogens' groups. Among seventy-nine bioactive myxobacteria, four isolates, KYC 3130, KYC 3247, KYC 3248 and KYC 3270, were selected and all were cellulolytic. Liquid culture filtrates of these four myxobacteria were applied to tomato, cherry tomato, strawberry, and kiwi fruits 5 h before inoculation with gray mold conidia; then the treated fruits were placed in an airtight container and the experiment was repeated six to eight times. Incidence (%) of gray mold on fruit of the infected control treatment was 84-98%, whereas it was only 5-21% after the KYC 3270 treatment. After KYC 3270 treatment of the four fruits, mold control was 79-95%, which was highest among the filtrates and statistically the same as treatment with fludioxonil, a registered chemical against gray mold of stored fruits.

Antifungal Activity of Nor-securinine Against Some Phytopathogenic Fungi

  • Sahni, Sangita;Maurya, S.;Singh, U.P.;Singh, A.K.;Singh, V.P.;Pandey, V.B.
    • Mycobiology
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    • 제33권2호
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    • pp.97-103
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    • 2005
  • Crude extracts and active principles from medicinal plants have shown potential role in controlling plant diseases in glasshouses as well as in fields as one of the safest and ecofriendly methods. The effect of nor-securinine (an alkaloid) isolated from Phyllanthus amarus has been seen against spore germination of some fungi (Alternaria brassicae, A. solani, Curvularia pennisetti, Curvularia sp., Erysiphe pisi, Helminthosporium frumentacei) as well as pea powdery mildew (Erysiphe pisi) under glasshouse conditions. The sensitivity of fungi to nor-securinine varied considerably. Nor-securinine was effective against most of the fungi. H. frumentacei was more sensitive even at the lowest concentration ($1,000\;{\mu}g/ml$). Likewise conidia of E. pisi were also inhibited in partially or completely appressorium formation. Pre-inoculation treatment showed greater efficacy than post-inoculation in inhibiting powdery mildew development on pea plants in a glasshouse. Maximum inhibition occurred at $2000\;{\mu}g/ml$.

Effects of Ionizing Radiation on Postharvest Fungal Pathogens

  • Jeong, Rae-Dong;Shin, Eun-Jung;Chu, Eun-Hee;Park, Hae-Jun
    • The Plant Pathology Journal
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    • 제31권2호
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    • pp.176-180
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    • 2015
  • Postharvest diseases cause losses in a wide variety of crops around the world. Irradiation, a useful nonchemical approach, has been used as an alternative treatment for fungicide to control plant fungal pathogens. For a preliminary study, ionizing radiations (gamma, X-ray, or e-beam irradiation) were evaluated for their antifungal activity against Botrytis cinerea, Penicillium expansum, and Rhizopus stolonifer through mycelial growth, spore germination, and morphological analysis under various conditions. Different fungi exhibited different radiosensitivity. The inhibition of fungal growth showed in a dose-dependent manner. Three fungal pathogens have greater sensitivity to the e-beam treatment compared to gamma or X-ray irradiations. The inactivation of individual fungal-viability to different irradiations can be considered between 3-4 kGy for B. cinerea and 1-2 kGy for P. expansum and R. stolonifer based on the radiosensitive and radio-resistant species, respectively. These preliminary data will provide critical information to control postharvest diseases through radiation.

벼 도열병균의 부차기 형성에 미치는 요인 분석 (Factors Affecting Appressorium Formation in the Rice Blast Fungus Magnaporthe grisea)

  • 이승철;강신호;이용환
    • 한국식물병리학회지
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    • 제14권5호
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    • pp.413-417
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    • 1998
  • Magnaporthe grisea, the casual agent of rice blast, requires formation of an appressorium, a dome-shaped and well melanized infection structure, to penetrate its host. Environmental cues that induce appressorium formation include hydrophobicity and hardness of contact surface and chemicals from its host. Artificial surfaces are widely used to induce appressorium formation, but frequencies of appressorium induction are not always consistent. To understand variable induction of appressorium formation in M. grisea, several factors were tested on GelBond. High levels of appressorium formation were induced over a wide range of temperature (20~3$0^{\circ}C$) and pH (4~7). spore age up to 3-week-old did not significantly affect appressorium formation, but only a few apressoria on GelBond. However, adenosine specifically inhibited appressorium formation. Adenosine inhibition of appressorium formation was restored by exogenous addition of cAMP. Germ tube tips of M. grisea maintained the ability to differentiate appressoria by chemical inducers on GelBond at least up to 16 h after conidia germination. These results suggest that environmental factors have little effect on the variable induction of appressorium formation on the artificial surface in M. grisea.

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