• 한국버섯학회지
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• 제21권4호
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• pp.195-199
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• 2023

The fungus Alternaria alternata, responsible for causing brown to black spotting on numerous fruits and vegetables globally, was identified in 2022 as the causative pathogen of brown spot disease in potatoes in Korea. In pursuing potential inhibitors against A. alternata growth, we evaluated 15 mushroom culture filtrates: eight from Trametes spp. and seven from Polyporus spp., known for their antibacterial and anticancer properties. Antifungal activity was assessed by exposing each filtrate to A. alternata on a paper disc. Four filtrates displayed inhibitory action against the fungus, albeit with mild effects. Our findings highlight the potential of Trametes and Polyporus fungi as emerging antifungal candidates, offering promise in preventing potato brown spots.

• 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.

• The Plant Pathology Journal
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• 제22권4호
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• pp.375-380
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• 2006

In the survey from 1992 to 2000, twenty-eight parasitic diseases were observed in major apple producing areas in Korea. The predominant apple diseases were white rot(Botryosphaeria dothidea), Marssonina blotch(Marssonina mali), Valsa canker(Valsa ceratosperma), Alternaria leaf spot(Alternaria mali), and bitter rot(Collectotrichum gloeosporioides and C. acutatum). Apple scab that reappeared in 1990 after disappearance for 15 years was disappeared again since 1997. A viroid disease(caused by apple scar skin viroid) was newly found in this survey. The five diseases, fire blight(Erwinia amylovora), black rot(Botryosphaeria obtusa), scab(Cladosporium carpophilum), Monochaetia twig blight(Monochaetia sp.), and brown leaf spot(Hendersonia mali), which had once described in 1928 but no further reports on their occurrence, were not found in this survey. However, blossom blight(Monilinia mali), brown rot(Monilinia fructigena), and pink rot(Trichothecium roseum), which did not occur on apple after mid 1970s, were found in this survey.

• 한국응용곤충학회지
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• 제19권4호
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• pp.221-227
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• 1980

1979년 7월 경남 김해에서 딸기 성강 16호의 잎에 흑갈색 내지 암갈색 병반을 형성하는 병해를 발견, 그 병원균을 분리 검토한 결과 우리나라에서는 미기록병해인 Alternaria alternate (Fr.) Keissler로 동정되었으며 본병을 검은무늬병이라 명명하였다. 본균의 분생포자의 형태는 배지간에 차가 심하였으며 C.M.A.에서 평균 $20.1\times9.3{\mu}$, beak의 길이는 $4.0{\mu}$으로서 자연감염된 딸기잎상에서 형성된 것 보다 짧았다. 딸기 49품종에 접종한 결과 성강 16호와 Robinson이 고도감수성이였으며 Catskill, Cyclone, Northwest, Merton princes, Juspa, 및 대학 1호 등의 품종에도 발병을 볼 수 있었으나 31 품종은 전연 발병되지 않았다. 10종(14품종)에 접종한 결과 해바라기, 겹해바라기, 및 멕시코 해바라기에만 심하게 발병되었다.

• The Plant Pathology Journal
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• 제30권3호
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• pp.323-329
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• 2014

Two cultivars Buram-3-ho (susceptible) and CR-Hagwang (moderate resistant) of kimchi cabbage seedlings showed differential defense responses to anthracnose (Colletotrichum higginsianum), black spot (Alternaria brassicicola) and black rot (Xanthomonas campestris pv. campestris, Xcc) diseases in our previous study. Defense-related hormones salicylic acid (SA), jasmonic acid (JA) and ethylene led to different transcriptional regulation of pathogenesis-related (PR) gene expression in both cultivars. In this study, exogenous application of SA suppressed basal defenses to C. higginsianum in the 1st leaves of the susceptible cultivar and cultivar resistance of the 2nd leaves of the resistant cultivar. SA also enhanced susceptibility of the susceptible cultivar to A. brassicicola. By contrast, SA elevated disease resistance to Xcc in the resistant cultivar, but not in the susceptible cultivar. Methyl jasmonate (MJ) treatment did not affect the disease resistance to C. higginsianum and Xcc in either cultivar, but it compromised the disease resistance to A. brassicicola in the resistant cultivar. Treatment with 1-aminocyclopropane-1-carboxylic acid (ACC) ethylene precursor did not change resistance of the either cultivar to C. higginsianum and Xcc. Effect of ACC pretreatment on the resistance to A. brassicicola was not distinguished between susceptible and resistant cultivars, because cultivar resistance of the resistant cultivar was lost by prolonged moist dark conditions. Taken together, exogenously applied SA, JA and ethylene altered defense signaling crosstalk to three diseases of anthracnose, black spot and black rot in a cultivar-dependent manner.

• 원예과학기술지
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• 제35권2호
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• pp.210-219
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• 2017

본 연구는 Alternaria brassicicola에 의해 발생하는 무 검은무늬병에 대한 효율적인 저항성 검정법을 확립하기 위하여 수행되었다. A. brassicicola 7균주의 포자 형성량과 병원성을 검정하였다. 실험한 균주 중, A. brassicicola KACC 40036과 43923 균주는 V-8 juice agar 배지에서 가장 많은 포자를 생산하였다. 그리고 실험한 균주 모두는 무 유묘에 대하여 강한 병원력을 나타냈다. 시판 중인 무 61개 품종의 A. brassicicola KACC 40036 균주에 대한 저항성 스크리닝을 수행하였다. 실험한 품종 중 높은 저항성을 보이는 품종은 없었으나 '금봉'과 '새롬'같이 약한 저항성을 나타내는 품종이 발견되었다. 이들 결과로부터 추후 실험을 위해 저항성 반응에 차이를 보이는 4개 품종을 선발하였다. 이들 4개 품종의 접종하는 무의 생육 시기, 접종원 농도 그리고 접종 후의 재배 온도에 따른 검은무늬병 발생을 조사하였다. 실험한 모든 품종은 어린 유묘일수록 검은무늬병에 대한 감수성이 증가하였으며, 더 많은 A. brassicicola 포자를 접종할수록 검은무늬병이 더 많이 발생하였다. 그리고 접종한 유묘를 $25^{\circ}C$의 습실상에서 배양하였을 때에는 $20^{\circ}C$ 나 $30^{\circ}C$에서 배양하였을 때보다 검은무늬병 발생이 증가하였다. 이들 실험의 결과로부터 무 품종의 검은무늬병에 대한 저항성을 검정하기 위해서는 무 종자를 파종하고 온실($25{\pm}5^{\circ}C$)에서 16일 동안 재배하고, 이 유묘에 A. brassicicola 균주의 포자현탁액($2.0{\times}10^5spores{\cdot}mL^{-1}$)을 분무하여 접종하고, 접종한 식물은 $25^{\circ}C$ 습실상에 24시간 동안 배양한 후에 $25^{\circ}C$, 상대습도 80%의 생육상에서 재배하고, 접종 2일 후에 병반면적율을 조사하는 것을 제안한다.

• Journal of Microbiology and Biotechnology
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• 제26권7호
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• pp.1311-1319
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• 2016

Alternaria brassicicola (Schwein.) invades Brassicaceae and causes black spot disease, significantly lowering productivity. Mitogen-activated protein kinases (MAPKs) and their upstream kinases, including MAPK kinases (MAPKKs) and MAPKK kinases (MAPKKK), comprise one of the most important signaling pathways determining the pathogenicity of diverse plant pathogens. The AbSte7 gene in the genome of A. brassicicola was predicted to be a homolog of yeast Ste7, a MAPKK; therefore, the function was characterized by generating null mutant strains with a gene replacement method. AbSte7 replacement mutants (RMs) had a slower growth rate and altered colony morphology compared with the wild-type strain. Disruption of the AbSte7 gene resulted in defects in conidiation and melanin accumulation. AbSte7 was also involved in the resistance pathways in salt and oxidative stress, working to negatively regulate salt tolerance and positively regulate oxidative stress. Pathogenicity assays revealed that AbSte7 RMs could not infect intact cabbage leaves, but only formed very small lesions in wounded leaves, whereas typical lesions appeared on both intact and wounded leaves inoculated with the wild-type strain. As the first studied MAPKK in A. brassicicola, these data strongly suggest that the AbSte7 gene is an essential element for the growth, development, and pathogenicity of A. brassicicola.

• 한국미생물·생명공학회지
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• 제30권1호
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• pp.51-56
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• 2002

국내 토양에서 분리한 식물성 병원균인 Alternaria brassicicola SW-3리 항암활성 물질 생산능을 조사하고, 활성물질을 분리 정제하여 구조를 확인하였다. A. brassicicola SW-3는potato dextrose broth를 이용하여 15$^{\circ}C$에서 2주간 진탕 배양한 다음, MTT assay를 실시하여 항암활성을 확인하였으며, 배양여액 중의 항암물질은 ethyl acetate로 추출하고, silica gel column chromatography로 정제하여 무색의 oily product를 얻었다(수율 22mg/m1). 분리된 물질은 물이나 hexane에는 녹지 않고, chloroform, ethyl acetate, ethanol 등에는 잘 녹는 특징을 보였으며, , $IR^{1}$H-NMR, $^{13}$C-NMR 등을 통해 구조를 분석한 결과, 최근에 일본에서 분리되어 항암효과가 있는 것으로 알려진 depudecin과 동일한 물질로 추정되었다. 본 실험에서 분리된 depudecin은 인체간암세포와 mouse 피부암세포에 대한 세포독성을 나타내었으며, 각각의$ IC_50$ 는 $57\mu$g/ml, $69\mu$g/ml로 나타났다. Alternaria brassicicola SW-3에 의해 생산된 물질이 기지의 물질이지만, depudecin은 아직 작용 기작이나 적용범위 등이 밝혀지지 않은 초기 연구 단계에 있는 물질로서, 새로운 항암제로서의 가능성이 매우 높아 이의 유도체를 합성하거나, 다른 항암제와의 혼용에 의해 부작용이 적은 강력한 항암제를 개발하기 위한 선도물질로 활용될 수 있을 것이다.

• The Plant Pathology Journal
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• 제36권2호
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• pp.157-169
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• 2020

Two lactic acid bacteria (LAB) designated J02 and J13 were recovered from fermented vegetables based on their ability to suppress soft rot disease caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) on radish. J02 and J13 were identified as Lactobacillus pentosus and Leuconostoc fallax, respectively. The ability of J02 and J13 to suppress plant diseases is highly dependent on chitosan. LAB alone has no effect and chitosan alone has only a moderate effect on disease reduction. However, J02 or J13 broth cultures plus chitosan display a strong inhibitory effect against plant pathogens and significantly reduces disease severity. LAB strains after being cultured in fish surimi (agricultural waste) and glycerol or sucrose-containing medium and mixed with chitosan, reduce three cruciferous vegetable diseases, including cabbage black spot caused by Alternaria brassicicola, black rot caused by Xanthomonas campestris pv. campestris, and soft rot caused by Pcc. Experimental trials reveal that multiple applications are more effective than a single application. In-vitro assays also reveal the J02/chitosan mixture is antagonistic against Colletotrichum higginsianum, Sclerotium rolfsii, and Fusarium oxysporum f. sp. rapae, indicating a broad-spectrum activity of LAB/chitosan. Overall, our results indicate that a synergistic combination of LAB and chitosan offers a promising approach to biocontrol.

• Applied Biological Chemistry
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• 제40권1호
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• pp.80-84
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• 1997

일련의 새로이 합성된 chira핀 N-치환 benzotriazol-1-yl유도체들의 구조와 잿빛 곰광이균(Botrytis cinerea), 배 검은 무늬병균(Alternaria kikchiana) 및 고추 역병균(Phytophthora capsici) 등 3종의 곰광이균류에 대한 항균활성에 미치는 치환기의 효과를 검토한 결과, 전자끌게(${\sigma}_I$,Y>0)로써 phenoxy 또는 thiophenoxy group(X) 보다는 alkyl또는 phenyl group(Y)이 더 큰 영향을 미쳤으며 phenoxy-치환체, 1이 thiophenoxy-치환체, 2보다 높은 항균활성을 나타내었다. 항균활성에 영향을 미치는 요인으로는 소수성(${\Sigma}logP$)과 유도효과(${\sigma}_I$,Y) 및 Van der Waals(${\Sigma}Vw$) 체적(${\AA}^3$) 등 이었으며 chiral성은 활성개선에 기여하지 못하였으나 tribromomethyl-치환체, 1g는 제일 큰 활성을 나타내는 화합물이었다.