• Mycobiology
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• 제32권4호
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• pp.160-163
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• 2004

Medicinal plants play important roles in controlling plant diseases as one of the safest and ecofriendly methods. These plants have been used in the form of crude extracts as well as active principles in vitro and under field conditions to control plant diseases. Among the active principles, alkaloids have shown significant antifungal activity. We have investigated the effect of two alkaloids viz., (-)-corydahnine and (-)-isocorypahnine isolated from Corydalis chaerophylla, against spore germination of some plant pathogenic and saprophytic fungal spores. Significant inhibition of spore germination at 100 ${\mu}g/ml$ was seen against Curvularia penniseti, Curvularia sp. and Colletotrichum gloeosporioides by (-)-corydahnine but (-)-isocorypalmine was also effective against fungi included in the experiment.

• 한국식물병리학회지
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• 제13권1호
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• pp.18-21
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• 1997

Bipolaris panici-miliacei, Cercospora fusimaculans, Fusarium moniliforme and Rhizoctonia solani were pathogenic fungi detected from 5 seed samples of common millet (Panicum miliaceum). Morphological characters of B. panici-miliacei were as follows. Conidiophores were dark olivaceous brown, simple, cylindrical, geniculate, and septate. Conidia were fusoid, dark olivaceous brown, tapering gradually toward the ends, straight to slightly curved, 3~13 distoseptate, and 29.4~155.4$\times$10~26 ${\mu}{\textrm}{m}$ in size with dark hilum included within the contour of the basal cell. Seed infection with B. panici-miliacei caused seed rotting, coleoptile spot, and seedling blight of common millet plants. According to the inoculation experiments, B. panici-miliacei showed strong virulence on the young seedlings of common millet, but very weak virulence on the young seedlings of rice (Oryza sativa) and foxtail millet (Setaria italica).

• 한국식물병리학회지
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• 제11권1호
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• pp.30-38
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• 1995

Anthracnose fungi associated with soybean (Glycine max), small red bean (Vigna angularis), and green bean (Phaseolus radiatus var. aurea) were compared with respect to cultural characteristics, morphological aspects, and pathogenicity. From the legumes, four different species of Colletotrichum were identified based on their morphological characters : C. truncatum, C. destructivum, C. trifolii and C. gloeosporioides. Colonies of Colletotrichum spp.on culture media varied in colour and growth habits depending upon the media and isolates. In general, formation of conidia, setae, and perithecia on water agar leaf medium was better than that on potato dextrose agar medium under near ultraviolet light. In cross inoculation tests, isolates of C. truncatum, c. destructivum, C. trifolii and C. gloeosporioides could infect soybean, small red bean, and green bean at different growth stages. There were some differences in pathogenicity or susceptibility depending on crops tested. C. truncatum was the most virulent and major pathogenic species among the four species.

• 한국균학회지
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• 제49권4호
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• pp.497-505
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• 2021

다양한 지역에서 채취한 참당귀(Angelica gigas Nakai)의 잎, 줄기, 뿌리에서 내생균을 분리하였다. 내생균 균주는 형태적특징과 ITS (internal transcribed spacer) 지역의 염기서열을 이용하여 동정하였다. 총 35종의 내생균이 동정되었다. 내생균의 다양성은 참당귀의 조직에 따라 다르게 나타났다. 분리된 내생균은 참당귀 점무늬병균 Phoma sp. Y11 균주와 대치배양하여 항균활성을 측정하였다. 총 14종의내생균이균주 Y11에대해억제효과를나타내었다. 본 연구는 참당귀에서 분리한 내생균이 참당귀의 점무늬병에 대한 생물학적 방제제로 사용될 수 있다는 것을 제시하고 있다.

• 한국균학회지
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• 제37권1호
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• pp.96-103
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• 2009

병원성 미생물을 방제하기 위하여 국내의 고추 재배지에서 탄저병균에 감염된 고추로부터 Bacillus속 균주를 분리하였다. 이들 중 고추탄저병균인 C. gloeosporioides 균주와 식물에 회색곰팡이병을 일으키는 Botrytis cinerea 균주에 대한 길항작용이 가장 우수한 Bacillus sp. IUB158-03을 선발하였다. 선발된 균주의 형태적, 생리 생화학적 특성과 MicroLog 방법을 이용하여 동정된된 균주는 B. amyloliquefaciens IUB158-03로 명명하였다. 항진균물질 생산을 위한 최적배지 조건은 2% soluble starch, 3% yeast extract, 0.5% tryptone, 0.5% $NH_4H_2PO_4$, 1% NaCl의 pH 6.0에서 $25^{\circ}C$, 72시간 배양한 추출물에서 가장 높은 항진균활성을 나타내었다. B. amyloliquefaciens IUB158-03이 생산한 항진균물질을 butanol로 추출한 후 silica gel column chromatography, preparative thin layer chromatography, and HPLC을 이용하여 항진균물질을 정제하였다. 정제된 항진균물질은 TLC plate 상에서 $R_f$값이 0.27인 것이 확인되었으며, 이 물질은 식물병원균인 Fusarium solani, Rhizoctonia solani, Botrytis cineria, Alternata alternaria와 인체병원성 진균인 Trichophyton mentagrophytes, Epidermophyton floccosum, Cryptococcus neoformans 등에만 선택적으로 높은 항진균 활성을 보였다.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1164-1169
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• 2005

Characteristics of sophorolipid and rhamnolipid were evaluated as antifungal agents against plant pathogenic fungi. Eight percent of mycelial growth of plant pathogen (Phytophthora sp. and Pythium sp.) was inhibited by 200 mg/l of rhamnolipid or 500 mg/l of sophorolipid, and zoospore motility of Phytophthora sp. decreased by $90\%$ at 50 mg/l of rhamnolipid and $80\%$ at 100 mg/l of sophorolipid. The effective concentrations for zoospore lysis were two times higher than those of zoospore motility inhibition. The highest zoospore lysis was observed with Phytophthora capsici; $80\%$ lysis at 100 mg/I of di-rhamnolipid or lactonic sophorolipid, showing the dependency of structure on the lysis. In the pot test, the damping-off disease incidence ratio decreased to $42\%\;and\;33\%$ of control value at 2,000 mg/l sophorolipid and rhamnolipid, respectively. These results showed the potential of microbial glycolipid biosurfactants as an effective antifungal agent against damping-off plant pathogens.

• 한국식품영양학회지
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• 제12권6호
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• pp.559-563
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• 1999

Essential oil of Artemisia lavandulaefolia the chrysanthemum family plant used in the chinese medicine was extracted and antibacterial and antifungal activity with many kinds of the pathogenic bacterium and fungi was experimented by it. Ataphylococcus epidermidis and Streptococcus aureus gram positive bacterium at the concentration of 200ppm and Streptococcus mutans at the concentration of 1,000ppm showed the growth injibition effect of the cell. These showed statistically significant difference(p<0.05) Zymomonas mobilis Entrecoccus faecalis gram negative bacterium at the concentration of 200ppm and Pseudomonas putida at the concentration of 400ppm showedd the growth inhibition effect of the cell)p<0.05) V. Parahaemolyticus at the concentration of 800ppm and Pseudomonas aeruginosa at the concentration of 1,000ppm showed the growth inhibition effect of the cell(p<0.05) Candida albicans and Cryptococcus neoformans yeast-type fungi showed the gorwth inhibition effect of the cell at the concentration of 200ppm(p<0.05) Altenaria mali Aspergillus nidulans and Fusarium oxysporum filamentous fungi took the growth inhibition effect of the cell at the concentration of 600ppm, 400ppm, and 100ppm. respectively.

• Mycobiology
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• 제35권2호
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• pp.62-64
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• 2007

An allosecurinine alkaloid was assayed against spore germination of some saprophytic and pathogenic fungi e.g., Alternaria alternata, A. solani, A. brassicicola, A. brassicae, Curvularia lunata, C. pallescens, C. maculans, Curvularia species, Colletotrichum species, C. musae, C. gloeosporioides, Erysiphe pisi, Fusarium udum, Helminthosporium echinoclova, H. pennisetti, H. spiciferum, and Heterosporium sp. It inhibited mild spore germination of all the fungi tested. Curvularia lunata, Curvularia sp., Collectotrichum sp., C. musae and Heterosporium sp. were most sensitive as complete inhibition of spore germination was observed at very low concentrations.

• 한국환경농학회지
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• 제30권3호
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• pp.346-356
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• 2011

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and ${\beta}$-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and ${\beta}$-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% $Na_2HPO_4$, 0.07% $KH_2PO_4$, 0.0001% $MgSO_4$, and 0.0001% $MnSO_4$ at $30^{\circ}C$. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi. CONCLUSION(S): This study demonstrated the multiantifungal enzyme production by Streptomyces sp. AM50 for the biological control of major plant pathogens. Further studies will investigate the synergistic effect, to the growth regulations by biogenic amines and antifungal enzyme gene promoter.

• 한국자원식물학회지
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• 제30권4호
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• pp.343-351
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• 2017

401종의 식물에서 얻은 메탄올 추출물 662개를 식물 병원성 곰팡이[딸기잿빛곰팡이병균(Botrytis sp.), 고추탄저병균(Colletotrichum sp.), 작약점무늬병균(Alternaria sp.) 및 작약검은뿌리썩음병균(Cylindrocarpon sp.)]에 대한 분생포자의 발아억제 활성을 microdilution assay로 측정하였다. 검정에 사용한 추출물 중에서 36종의 추출물이 1종 이상의 곰팡이에 대하여 억제활성을 보였다. 짚신나물, 고본, 족도리풀, 일천궁, 백선 및 목향의 뿌리, 능소화의 잎가지, 감초의 지상부, 뽕나무의 가지 추출물은 식물의 지상부 조직에서 발병하는 균(Botrytis sp., Colletotrichum sp. 그리고 Alternaria sp.)과 뿌리에 발병하는 균(Cylindrocarpon sp.)의 포자발아를 모두 억제하는 항균활성을 보여 주어 이들 추출물의 항균범위가 넓은 것으로 나타났다. 각각의 곰팡이 대한 추출물의 억제활성을 보면, 뽕나무의 가지와 고삼의 뿌리 추출물은 1,250 mg/L에서 딸기잿빛곰팡이병균의 포자발아를 완전히 억제하였다. 고추탄저병균의 포자발아억제에 가장 강한 추출물은 홀아비꽃대의 뿌리였으며, $1,250{\mu}g/ml$에서 완전히 억제하였다. 작약점무늬병균에 가장 강한 억제활성을 나타낸 추출물은 감초의 지상부였으며, $625{\mu}g/ml$에서 포자의 발아를 100% 억제하였고, 새모래덩굴의 뿌리와 뽕나무 가지 추출물은 $1,250{\mu}g/ml$에서 억제하였다. 작약검은뿌리썩음병균에 가장 강한 억제활성을 나타낸 추출물은 감초의 지상부와 목향의 뿌리였으며, $1,250{\mu}g/ml$에서 포자발아를 억제하였다.