• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.167-170
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• 2008

A fungal strain BCP, which parasitizes Botrytis cinerea gray mold pathogen, was isolated and identified as Acremonium strictum. BCP strain overgrew the colonies of B. cinerea and caused severe lysis of the host hyphae. Frequent penetration and hyphal growth of A. strictum BCP inside the mycelia of B. cinerea were observed under light microscopy. In addition, some morphological abnormalities such as granulation and vacuolation of the cytoplasm were observed in mycelia and spores of B. cinerea. In dual culture test, A. strictum BCP strongly inhibited the mycelial growth of several plant pathogenic fungi as well as B. cinerea. To our knowledge, this is the first report on mycoparasitism of Acremonium species on B. cinerea.

• Mycobiology
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• 제37권4호
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• pp.308-309
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• 2009

Powdery mildews on over 40 plants in Bangalore were screened during July-December of 2003~2008. Isolates from mycoparasitised Oidium caesalpiniacearum of Bauhinia purpurea comprised Lasiodiplodia theobromae, in addition to Ampelomyces quisqualis. Koch's postulates were satisfied to establish the mycoparasitism of L. theobromae. This is the first report that L. theobromae acts as a mycoparasite of a powdery mildew.

• Mycobiology
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• 제43권2호
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• pp.107-117
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• 2015

A mycoparasite, Scytalidium parasiticum sp. nov., isolated from the basidiomata of Ganoderma boninense causing basal stem rot of oil palm in Johor, Malaysia, is described and illustrated. It is distinct from other Scytalidium species in having smaller asci and ascospores (teleomorphic stage), longer arthroconidia (anamorphic stage), hyaline to yellowish chlamydospores, and producing a fluorescent pigment. The phylogenetic position of S. parasiticum was determined by sequence analyses of the internal transcribed spacers and the small-subunit ribosomal RNA gene regions. A key to identify Scytalidium species with teleomorphic stage is provided.

• Journal of Ginseng Research
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• 제40권4호
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• pp.315-324
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• 2016

Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

• Journal of Ginseng Research
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• 제43권3호
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• pp.408-420
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• 2019

Background: Ginseng (Panax ginseng Meyer) is an invaluable medicinal plant containing various bioactive metabolites (e.g., ginsenosides). Owing to its long cultivation period, ginseng is vulnerable to various biotic constraints. Biological control using endophytes is an important alternative to chemical control. Methods: In this study, endophytic Trichoderma citrinoviride PG87, isolated from mountain-cultivated ginseng, was evaluated for biocontrol activity against six major ginseng pathogens. T. citrinoviride exhibited antagonistic activity with mycoparasitism against all ginseng pathogens, with high endo-1,4-${\beta}$-D-glucanase activity. Results: T. citrinoviride inoculation significantly reduced the disease symptoms caused by Botrytis cinerea and Cylindrocarpon destructans and induced ginsenoside biosynthesis in ginseng plants. T. citrinoviride was formulated as dustable powder and granules. The formulated agents also exhibited significant biocontrol activity and induced ginsenosides production in the controlled environment and mountain area. Conclusion: Our results revealed that T. citrinoviride has great potential as a biological control agent and elicitor of ginsenoside production.

• Mycobiology
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• 제50권4호
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• pp.244-253
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• 2022

Trichoderma fungi have been intensively studied for mycoparasitism, and the latter is closely related to their cell-wall degrading enzymes including chitinase. Here, we studied marine-derived Trichoderma spp., isolated from distinct sources and locations, for chitinolytic and antifungal activity. Based on morphological and phylogenetic analyses, two strains designated GJ-Sp1 and TOP-Co8 (isolated from a marine sponge and a marine alga, respectively) were identified as Trichoderma bissettii. This species has recently been identified as a closely related species to Trichoderma longibrachiatum. The extracellular crude enzymes of GJ-Sp1 and TOP-Co8 showed activities of chitobiosidase and b-N-acetylglucosaminidase (exochitinase) and chitotriosidase (endochitinase). The optimum chitinolytic activity of the crude enzymes was observed at 50 ℃, pH 5.0, 0-0.5% NaCl concentrations, and the activities were stable at temperatures ranging from 10 to 40 ℃ for 2 h. Moreover, the crude enzymes showed inhibitory activity against hyphal growth of two filamentous fungi Aspergillus flavus and Aspergillus niger. To the best of our knowledge, this is the first report of the chitinolytic and antifungal activity of T. bissettii.

• 한국균학회지
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• 제4권1호
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• pp.45-52
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• 1976

기생미생물(寄生微生物)에 대한 연구(硏究)에서 숙주(宿主)와 기생균(寄生菌)을 분류동정(分類同定)하고 성장과정(成長過程)과 그 처리조직학적(處理組織學的) 해부학적(解剖學的) 구조(構造)를 광학(光學) 및 전자현미경(電子顯微鏡)을 통하여 관찰(觀察)하고, 이종간(二種間)의 상호관계(相互關係)를 구명(究明)한 결과(結果)는 다음과 같다. 1. 숙주(宿主)와 기생균(寄生菌)은 Aspergillus niger와 Penicillium rugulosum으로 각각 동정(同定)되었다. 2. 기생균(寄生菌)은 숙주(宿主)의 Sterigmata에 기생(寄生)하고 있는 것을 관찰(觀察)하였다. 3. 기생상태(寄生狀態)의 진행(進行)에 따라 숙주(宿主)의 세포(細胞) 내용물(內容物)이 소실(消失)되어 간다. 4. 기생균(寄生菌)은 합성배지(合成培地)에서도 배양(培養)되므로 활물기생(活物寄生)이 아니다.

• The Plant Pathology Journal
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• 제31권1호
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• pp.50-60
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• 2015

The use of novel isolates of Trichoderma with efficient antagonistic capacity against Fusarium oxysporum f. sp. lycopersici (FOL) is a promising alternative strategy to pesticides for tomato wilt management. We evaluated the antagonistic activity of 30 isolates of T. asperellum against 4 different isolates of FOL. The production of extracellular cell wall degrading enzymes of the antagonistic isolates was also measured. The random amplified polymorphic DNA (RAPD) method was applied to assess the genetic variability among the T. asperellum isolates. All of the T. asperellum isolates significantly reduced the mycelial growth of FOL isolates but the amount of growth reduction varied significantly as well. There was a correlation between the antagonistic capacity of T. asperellum isolates towards FOL and their lytic enzyme production. Isolates showing high levels of chitinase and ${\beta}$-1,3-glucanase activities strongly inhibited the growth of FOL isolates. RAPD analysis showed a high level of genetic variation among T. asperellum isolates. The UPGMA dendrogram revealed that T. asperellum isolates could not be grouped by their antagonistic behavior or lytic enzymes production. Six isolates of T. asperellum were highly antagonistic towards FOL and potentially could be used in commercial agriculture to control tomato wilt. Our results are consistent with the conclusion that understanding the genetic variation within Trichoderma isolates and their biochemical capabilities are required for the selection of effective indigenous fungal strains for the use as biocontrol agents.