• Mycobiology
• /
• 제42권3호
• /
• pp.286-290
• /
• 2014

Fungi are the known sources of irritation associated with atopic diseases (e.g., asthma, allergic rhinoconjunctivitis, and atopic eczema). To quantitatively estimate their presence in the indoor environment of atopic dermatitis-inflicted child patient's houses (ADCPHs), the high-efficiency particulate air (HEPA) filters installed inside the air cleaners of three different ADCPHs were investigated for the presence of mold. The air cleaner HEPA filters obtained from the three different ADCPHs were coded as HEPA-A, -B, and -C, respectively, and tested for the presence of mold. The colony forming units (CFUs) corresponding to the HEPA-A, -B, and -C filters were estimated to be $6.51{\times}10^2{\pm}1.50{\times}10^2CFU/cm^2$, $8.72{\times}10^2{\pm}1.69{\times}10^2CFU/cm^2$, and $9.71{\times}10^2{\pm}1.35{\times}10^2CFU/cm^2$, respectively. Aspergillus, Penicillium, Alternaria, Cladosporium, Trichoderma, and other fungal groups were detected in the 2,494 isolates. The distribution of these fungal groups differed among the three filters. Cladosporium was the major fungal group in filters HEPA-A and -C, whereas Penicillium was the major fungal group in the filter HEPA-B. Nine fungal species, including some of the known allergenic species, were identified in these isolates. Cladosporium cladosporioides was the most common mold among all the three filters. This is the first report on the presence of fungi in the air cleaner HEPA filters from ADCPHs in Korea.

• Mycobiology
• /
• 제45권4호
• /
• pp.401-408
• /
• 2017

Colletotrichum gloeosporioides is an economically important fungal pathogen causing substantial yield losses indifferent host plants. To understand the genetic diversity and molecular epidemiology of this fungus, we have developed a novel, high-resolution multi-locus microsatellite typing (MLMT) method. Bioinformatic analysis of C. gloeosporioides unannotated genome sequence yielded eight potential microsatellite loci, of which five, CG1 $(GT)_n$, CG2 $(GT1)_n$, CG3 $(TC)_n$, CG4 $(CT)_n$, and CG5 $(CT1)_n$ were selected for further study based on their universal amplification potential, reproducibility, and repeat number polymorphism. The selected microsatellites were used to analyze 31 strains of C. gloeosporioides isolated from 20 different host plants from India. All microsatellite loci were found to be polymorphic, and the approximate fragment sizes of microsatellite loci CG1, CG2, CG3, CG4, and CG5 were in ranges of 213-241, 197-227, 231-265, 209-275, and 132-188, respectively. Among the 31 isolates, 55 different genotypes were identified. The Simpson's index of diversity (D) values for the individual locus ranged from 0.79 to 0.92, with the D value of all combined five microsatellite loci being 0.99. Microsatellite data analysis revealed that isolates from Ocimum sanctum, Capsicum annuum (chili pepper), and Mangifera indica (mango) formed distinct clusters, therefore exhibited some level of correlation between certain genotypes and host. The developed MLMT method would be a powerful tool for studying the genetic diversity and any possible genotype-host correlation in C. gloeosporioides.

• Journal of Ginseng Research
• /
• 제47권6호
• /
• pp.773-783
• /
• 2023

Background: Gray mold, caused by Botrytis cinerea, is one of the major fungal diseases in agriculture. Biological methods are preferred over chemical fungicides to control gray mold since they are less toxic to the environment and could induce the resistance to pathogens in plants. In this work, we try to understand if ginseng defense to B. cinerea could be induced by fungal hypovirulent strain △BcSpd1. BcSpd1 encodes Zn(II)₂Cys₆ transcription factor which regulates fungal pathogenicity and we recently reported △BcSpd1 mutants reduced fungal virulence. Methods: We performed transcriptomic analysis of the host to investigate the induced defense response of ginseng treated by B. cinerea △BcSpd1. The metabolites in ginseng flavonoids pathway were determined by UPLC-ESI-MS/MS and the antifungal activates were then performed. Results: We found that △BcSpd1 enhanced the ginseng defense response when applied to healthy ginseng leaves and further changed the metabolism of flavonoids. Compared with untreated plants, the application of △BcSpd1 on ginseng leaves significantly increased the accumulation of p-coumaric acid and myricetin, which could inhibit the fungal growth. Conclusion: B. cinerea △BcSpd1 could effectively induce the medicinal plant defense and is referred to as the biological control agent in ginseng disease management.

• 한국가금학회지
• /
• 제16권3호
• /
• pp.175-192
• /
• 1989

한국 양계의 성장기이었던 1971년부터 1988년까지 최근 18연간 국내 양계농가로부터 농촌진흥청 가축위생연구소에 의뢰된 닭 가검물의 병성감정결과 질병검색된 총 9,012건 중 전염성 질병으로 진단된 6,181건에 대하여 검색 연도별, 계절별 및 일영별 검색상황을 조사 분석하였던 바 다음과 같은 결과를 얻었다. 1. 연도별 전염성 질병의 검색률은 49.3％(1973연)∼78.3％(1985년)로써 연평균 68.6％로 나타나 비전염성 질병(31.42％)보다는 월등히 높았다. 2. 전염성 질병 중에는 세균성이 32.6％(16.2∼42.5％)로 가장 높았고 다음 바이러스성 질병이 26.3％(21.8∼38.1％)이었으며 기생충성 및 곰팡이성 질병은 각각 7.7％ 및 2.1％의 낮은 검색율을 나타내었다. 3. 세균성 질병으로는 마이코프라스마병, 대장균증 및 포도상구균증의 연평균검색률이 각각 8.8％, 8.5％, 5.8％로 가장 높았으며, 다음 살모넬라균증, 추백리, 난황염 및 수란괌염이 각각 0.8∼1.5％ 이었고 피부염(0.2％) 및 연쇄상구균증(0.1％)은 매우 낮은 빈도로 검색되었다. 4. 바이러스성 질병중에는 임파성 백혈병 및 마렉병이 각각 연평균 7.5％ 및 7.2％로 가장 많았고 다음 뉴캣슬병(4.4％), 전염성 후두기관염(2.0％), 전염성 낭병(1. 7％) 및 조뇌척수염(1.0％)의 순이었으며 그 외 전염성 기관지염, 산란저하증 '76 및 봉입체간염 등이 각각 1.0％, 미만으로 검색되었다. 5. 기생충성 질병의 검색률에 있어서는 닭 콕시듐병이 연평균 4.5％로 가장 높았고 다음 회염증이 1.4％이었다. 그 외에 류코싸이토준병 흑두병, 맹장충증 및 외부기생충증이 각각 0.2∼0.7％의 낮은 비율로 검색되었다. 곰팡이성 질병으로는 곰팡이성 폐렴이 연평균 2.0％, 다음으로 캔디다증이 0.1％ 검색되었다. 6. 계절별 전염성 질병의 검색은 하계 및 추계절에 각각 27.7％ 검색되어 가장 높았으며 다음 동계(23.5％) 및 춘계절의 순으로 낮았다. 이들중 세균성, 바이러스성 및 곰팡이성 질병은 이와 유사한 경향이었으나 기생충성 질병은 하계 및 추계절에서의 검색률이 각각 34.3％ 및 39.5％로 다른 계절에 비하여 월등히 높았다. 7. 세균성 포도장구균증은 추계절에서의 검색율이 가장 높았으며, 바이러스성 질병으로는 마렉병, 전염성 후두기관염 및 전염성 낭병은 하계절에, 그리고 임파성백혈병, 계두 및 산란저하증 '76은 추계절에서 가장 높았으며 전염성 기관지염은 동계절에 최고빈도로 검색되었다. 기생충성 질병에 있어서는 콕시듐병을 위시하여 회충증, 류코싸이토준병 및 흑두병등 대부분의 주요질병이 하계절 및 추계절에 가장 많이 검색되었다. 8. 닭 일영별 전염성 질병의 검색률은 육성계(30∼150일영)에서 47.4％의 가장 높은 검색률을 나타내었고 다음 성계(150일영이상)에서 35.3％ 및 유추(30 일영미만)에서 17.3％의 순이었다. 이중 세균성 및 기생충성 질병은 육성계에서의 검색률이 가장 높았으나, 바이러스성 질병은 육성계 및 성계에서 거의 같은 비율로 높았으며 곰팡이성 질병은 유추에서 가장 높은 검색률을 나타내었다.

• Mycobiology
• /
• 제39권1호
• /
• pp.26-32
• /
• 2011

Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo. Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination.

• Journal of Microbiology and Biotechnology
• /
• 제28권11호
• /
• pp.1771-1781
• /
• 2018

The emergence of multidrug-resistant microorganisms, as well as fungal infectious diseases that further threaten health, especially in immunodeficient populations, is a major global problem. The development of new antifungal agents in clinical trials is inferior to the incidence of drug resistance, and the available antifungal agents are restricted. Their mechanisms aim at certain characteristics of the fungus in order to avoid biological similarities with the host. Synthesis of the cell wall and ergosterol are mainly targeted in clinical use. The need for new approaches to antifungal therapeutic agents or development alternatives has increased. This review explores new perspectives on mechanisms to effectively combat fungal infections and effective antifungal activity. The clinical drug have a common feature that ultimately causes caspase-dependent cell death. The drugs-induced cell death pathway is associated with mitochondrial dysfunction, including mitochondrial membrane depolarization and cytochrome c release. This mechanism of action also reveals antimicrobial peptides, the primary effector molecules of innate systems, to highlight new alternatives. Furthermore, drug combination therapy is suggested as another strategy to combat fungal infection. The proposal for a new approach to antifungal agents is not only important from a basic scientific point of view, but will also assist in the selection of molecules for combination therapy.

• The Plant Pathology Journal
• /
• 제37권4호
• /
• pp.347-355
• /
• 2021

Ripe rot caused by Botryosphaeria dothidea is one of the serious diseases of postharvest kiwifruit. In order to control ripe rot on Actinidia chinensis cultivar 'Zesy002', several commercial agrofungicides were selected by an antifungal test on an artificial medium. Furthermore, disease suppression by the selected fungicides was evaluated on the kiwifruit by inoculation with a conidial suspension of B. dothidea. On the artificial media containing boscalid + fludioxonil was shown to be the most effective antifungal activity. However, in the bio-test pyraclostrobin + boscalid and iminoctadinetris were the most effective agrochemicals on the fruit. On the other hand, the infection structures of B. dothidea on kiwifruit treated with pyraclostrobin + boscalid were observed with a fluorescent microscope. Most of the fungal conidia had not germinated on the kiwifruit treated with the agrochemicals whereas on the untreated fruit the fungal conidia had mostly germinated. Electron microscopy of the fine structures showed morphological changes to the conidia and branch of hyphae on the kiwifruit pre-treated with pyraclostrobin + boscalid, indicating its suppression effect on fungal growth. Based on this observation, it is suggested that ripe rot by B. dothidea may be suppressed through the inhibition of conidial germination on the kiwifruit treated with the agrochemicals.

• 식물병연구
• /
• 제29권2호
• /
• pp.130-136
• /
• 2023

Citrus melanoses caused by Diaporthe citri, has been one of the serious diseases in many citrus orchards of Jeju Island. To protect melanose in citrus farms, a fast and exact diagnosis method is necessary. In this study, diseased leaves and dieback twigs were collected from a total of 49 farms within March to April in 2022. A total of 465 fungal isolates were obtained from a total of 358 isolated plant samples. Among these fungal isolates, 40 representatives of D. citri isolates which were isolated from 22 twigs and 18 leaves on 23 farms were found based on cultural characteristics on potato dextrose agar and conidial morphology. Additionally, the molecular assay was carried out and compared with those by morphological diagnosis. All isolates were identified as D. citri by analyzing the sequences at the internal transcribed spacer (ITS) rDNA region using primers of ITS1/ITS4 or at β-tubulin using primer Btdcitri-F/R. Therefore, based on the present study, where the results of morphological identification of conidial type were consistent with DNA sequence analysis of certain gene, choosing a suitable method for a fast diagnosis of citrus melanose was suggested.

• The Plant Pathology Journal
• /
• 제26권2호
• /
• pp.178-184
• /
• 2010

Four major diseases of chili pepper including two fungal diseases, anthracnose (Colletotrichum acutatum) and Phytophthora blight (Phytophthora capsici), and two bacterial diseases, bacterial wilt (Ralstonia solanacearum) and bacterial spot (Xanthomonas campestris pv. vesicatoria), were investigated under future climate-change condition treatments in growth chambers. Treatments with elevated $CO_2$ and temperature were maintained at $720ppm{\pm}20ppm$ $CO_2$ and $30^{\circ}C{\pm}0.5^{\circ}C$, whereas ambient conditions were maintained at $420ppm{\pm}20ppm$ $CO_2$ and $25^{\circ}C{\pm}0.5^{\circ}C$. Pepper seedlings or fruits were infected with each pathogen, and then the disease progress was evaluated in the growth chambers. According to paired t-test analyses, bacterial wilt and spot diseases significantly increased by 24% (p=0.008) and 25% (p=0.016), respectively, with elevated $CO_2$ and temperature conditions. On the other hand, neither Phytophthora blight (p=0.906) nor anthracnose (p=0.125) was statistically significant. The elevated $CO_2$ and temperature accelerated the progress of bacterial wilt by two days and bacterial spot by one day compared to the ambient treatment. Temperature regime studies of the diseases without changes in $CO_2$ confirmed that the accelerated bacterial disease progress was mainly due to the increased temperature rather than the elevated $CO_2$ conditions.

• Journal of Biosystems Engineering
• /
• 제23권5호
• /
• pp.499-506
• /
• 1998

전문가시스템 개발 도구인 HCLIPS를 이용하여 오이의 병해 및 영양 장애 진단을 위한 전문가시스템이 개발하였다. 농민과의 접견 및 문헌 조사를 통해서 지식베이스를 구축하였으며, 사용자의 이해를 돕기 위해 병해 및 영향 장애의 영상 자료를 포장 촬영 등을 통해서 얻었다. 개발된 전문가시스템을 잘록병 등 11가지의 병해와 질소 결핍 등 12가지의 영양 장애를 진단할 수 있으며, 진단 결과에 대한 상세한 설명과 농약 사용법 등의 방제 대책까지 제공한다. 이 전문가시스템에 대해서 농민 및 전문가들을 대상으로 진단의 정확도 및 사용 편리성을 검증을 수행한 결과, 확신도의 차이는 있었으나 100%의 진단 정확도를 나타냈으며, 검사대상자의 88%가 사용하기에 편리하다고 답하였다.