• The Plant Pathology Journal
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• 제37권6호
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• pp.505-511
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• 2021

Interaction of a pathogen with its host plant requires both flexibility and rapid shift in gene expression programs in response to environmental cues associated with host cells. Recently, a growing volume of data on the diversity and ubiquity of internal RNA modifications has led to the realization that such modifications are highly dynamic and yet evolutionarily conserved system. This hints at these RNA modifications being an additional regulatory layer for genetic information, culminating in epitranscriptome concept. In plant pathogenic fungi, however, the presence and the biological roles of RNA modifications are largely unknown. Here we delineate types of RNA modifications, and provide examples demonstrating roles of such modifications in biology of filamentous fungi including fungal pathogens. We also discuss the possibility that RNA modification systems in fungal pathogens could be a prospective target for new agrochemicals.

• The Plant Pathology Journal
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• 제31권3호
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• pp.278-289
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• 2015

Indigenous strains of Trichoderma species isolated from rhizosphere soils of Tea gardens of Assam, north eastern state of India were assessed for in vitro antagonism against two important tea fungal pathogens namely Pestalotia theae and Fusarium solani. A potent antagonist against both tea pathogenic fungi, designated as SDRLIN1, was selected and identified as Trichoderma viride. The strain also showed substantial antifungal activity against five standard phytopathogenic fungi. Culture filtrate collected from stationary growth phase of the antagonist demonstrated a significantly higher degree of inhibitory activity against all the test fungi, demonstrating the presence of an optimal blend of extracellular antifungal metabolites. Moreover, quantitative enzyme assay of exponential and stationary culture filtrates revealed that the activity of cellulase, ${\beta}$-1,3-glucanase, pectinase, and amylase was highest in the exponential phase, whereas the activity of proteases and chitinase was noted highest in the stationary phase. Morphological changes such as hyphal swelling and distortion were also observed in the fungal pathogen grown on potato dextrose agar containing stationary phase culture filtrate. Moreover, the antifungal activity of the filtrate was significantly reduced but not entirely after heat or proteinase K treatment, demonstrating substantial role of certain unknown thermostable antifungal compound(s) in the inhibitory activity.

• Mycobiology
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• 제30권4호
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• pp.233-239
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• 2002

The main aim of this study is to evaluate the efficiency of two biologically active compounds(Strom and F-760) in control of wheat root rot disease and its causal organisms. Fusarium graminearum, F. oxysporum, F. solani and Bipolaris sorokiniana were used as target organisms. In vitro, the two compounds showed fungicidal effect on all investigated pathogens resulted in suppression of radial growth and mycelial dry weight of them. Under greenhouse conditions, treatment of wheat grains with either Strom or F-760 before cultivation significantly reduced the percent of disease distribution as well as the mean disease rating of plants in both seedling and flowering stages. Fresh and dry weights of plants as well as water maintenance capacity were increased as the result of applying these compounds as seed dressing. Also data showed that the membrane stability of plants was injured as a result of infection with all investigated organisms, while this injury was alleviated when F-760 and Strom were applied. The $K^+$ efflux and the leakage of UV absorbing metabolites was stimulated with fungal infection. However, F-760 and Storm treatment partially retarded the stimulatory effect on leakage of $K^+$ and UV-absorbing metabolites of fungal infected plants. On the other side, the fungal infection had inhibitory effects on pigment fractions(chlorophyll a, b, and carotenoids) biosynthesis in wheat leaves. This retarding effect was partially or completely alleviated as the grains were treated with the applied compounds.

• Mycobiology
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• 제41권2호
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• pp.67-72
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• 2013

Pathogenic microbes secrete various enzymes with lipolytic activities to facilitate their survival within the host. Lipolytic enzymes include extracellular lipases and phospholipases, and several lines of evidence have suggested that these enzymes contribute to the virulence of pathogenic fungi. Candida albicans and Cryptococcus neoformans are the most commonly isolated human fungal pathogens, and several biochemical and molecular approaches have identified their extracellular lipolytic enzymes. The role of lipases and phospholipases in the virulence of C. albicans has been extensively studied, and these enzymes have been shown to contribute to C. albicans morphological transition, colonization, cytotoxicity, and penetration to the host. While not much is known about the lipases in C. neoformans, the roles of phospholipases in the dissemination of fungal cells in the host and in signaling pathways have been described. Lipolytic enzymes may also influence the survival of the lipophilic cutaneous pathogenic yeast Malassezia species within the host, and an unusually high number of lipase-coding genes may complement the lipid dependency of this fungus. This review briefly describes the current understanding of the lipolytic enzymes in major human fungal pathogens, namely C. albicans, C. neoformans, and Malassezia spp.

• Journal of Microbiology and Biotechnology
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• 제22권5호
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• pp.585-591
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• 2012

The antagonistic effect of Trichoderma harzianum on a range of seed-borne fungal pathogens of wheat (viz. Fusarium graminearum, Bipolaris sorokiniana, Aspergillus spp., and Penicillium spp.) was assessed. The potential of T. harzianum as a biocontrol agent was tested in vitro and under field conditions. Coculture of the pathogens and Trichoderma under laboratory conditions clearly showed dominance of T. harzianum. Under natural conditions, biocontrol effects were also obtained against the test fungi. One month after sowing, field emergence (plant stand) was increased by 15.93% over that obtained with the control treatment, and seedling infection was reduced significantly. Leaf blight severity was decreased from 22 to 11 at the heading stage, 35 to 31 at the flowering stage, and 86 to 74 at the grain filling stage. At harvest, the number of tillers per plant was increased by 50%, the yield was increased by 31.58%, and the 1,000-seed weight was increased by 21%.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2009년도 International Meeting of the Microbiological Society of Korea
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• pp.147-147
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• 2009

• Mycobiology
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• 제46권4호
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• pp.370-381
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• 2018

Bioactive natural compounds, isolated from fungal endophytes, play a promising role in the search for novel drugs. They are an inspiring source for researchers due to their enormous structural diversity and complexity. During the present study fungal endophytes were isolated from a well-known medicinal shrub, Berberis aristata DC. and were explored for their antagonistic and antioxidant potential. B. aristata, an important medicinal shrub with remarkable pharmacological properties, is native to Northern Himalayan region. A total of 131 endophytic fungal isolates belonging to eighteen species and nine genera were obtained from three hundred and thirty surface sterilized segments of different tissues of B. aristata. The isolated fungi were classified on the basis of morphological and molecular analysis. Diversity and species richness was found to be higher in leaf tissues as compared to root and stem. Antibacterial activity demonstrated that the crude ethyl acetate extract of 80% isolates exhibited significant results against one or more bacterial pathogens. Ethyl acetate extract of Alternaria macrospora was found to have potential antibacterial activity. Significant antioxidant activity was also found in crude ethyl acetate extracts of Alternaria alternata and Aspergillus flavus. Similarly, antagonistic activity of the fungal endophytes revealed that all antagonists possessed inhibition potential against more than one fungal pathogen. This study is an important step towards tapping endophytic fungal diversity for bioactive metabolites which could be a step forward towards development of novel therapeutic agents.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.87.3-88
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• 2003

TiO$_2$photocatalytic ozonation was attempted to disinfect fungal pathogens causing postharvest spoilage of kiwifruits and to decompose fungicide residuals on kiwifruits. TiO$_2$Photocatalytic ozonation process synergistically degraded organic compound and inhibited conidial germination of the fungal pathogen compared to single treatment of ozonation or photocatalysis. The efficient control of fungal spoilage and degradation of residual fungicide on kiwifruits indicate that TiO$_2$photocatalytic ozonation is a very attractive method for postharvest disease control of kiwifruits as an alternative to fungicides application.

• 한국식물병리학회지
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• 제14권1호
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• pp.52-61
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• 1998

This paper is the fifth report about the fungal diseases of economic resource plants observed newly in Korea. It contains short descriptions on symptoms, occurrence conditions, pathogens, and some phytopathological notes for each of 10 fungal plant diseases. They are identified as leaf spot of Adenophora triphylla var. japonica by Septoria lengyelii, leaf spot of Calystegia soldanella by S. convolvuli, leaf spot of Campanula punctata by S. campanulae, leaf spot of Codonopsis lanceolata by S. codonopsidis, leaf spot of Geum japonicum by s. gei, black spot of Oenanthe javanica by s. oenanthes, leaf spot of Oenothera odorata by S. oenotherae, angular leaf spot of Rehmannia glutinosa by S. digitalis, brown spot of Rubus crataegifolius by s. rubi, and leaf spot of Viola verecunda by S. violae-palustris, respectively.

• 한국식물병리학회지
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• 제14권5호
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• pp.473-483
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• 1998

This paper is the sixth report about the fungal diseases of economic resource plants observed newly in Korea. It contains short descriptions on symptoms, occurrence conditions, pathogens, and some phytopathological notes for each of 10 fungal plant diseases. They are identified as circular leaf spot of Ligustrum ovalifolium by Cercospora adusta, leaf spot of Viola spp. by c. violae, leaf spot of Trifolium repens by C. zebrina, hypophyllous leaf sot of Angelica gigas by Passalora depressa, brown leaf spot of Euonymus japonicus by Pseudocercospora destructiva, brown leaf spot of Lonicera japonica by P. lonicericola, brown leaf spot of Parthenocissus tricuspidata by P. vitis, black spot of Echinops latifolius by Ramularia cynarae, leaf spot of Petasites japonicus by R. major, and leaf spot of Plantagoasiactica by R. plantaginis, respectively.