• Mycobiology
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• 제49권5호
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• The Plant Pathology Journal
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• 제29권1호
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• pp.77-86
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• 2013

Anthracnose development by Colletotrichum musae was observed to be significantly less in the fruits of the banana cultivar 'Embul' (Mysore, AAB) infected with Phyllosticta musarum than in fruits without such infections. Anthracnose disease originates from quiescent C. musae infections in the immature fruit. P. musarum incites minute, scattered spots, referred to as freckles, in the superficial tissues of immature banana peel which do not expand during maturation or ripening. P. musarum does not appear to have a direct suppressive effect on C. musae as conidia of C. musae germinate on both freckled and non-freckled fruit forming quiescent infections. Our investigations have shown that P. musarum infection induced several defence responses in fruit including the accumulation of five phytoalexins, upregulation of chitinase and ${\beta}$-1,3-glucanase, phenylalanine ammonia lyase (PAL) activity and cell wall lignification. $^1H$ and $^{13}C$ NMR spectral data of one purified phytoalexin compared closely with 4'-hydroxyanigorufone. Some of the P. musarum-induced defences that retained during ripening, restrict C. musae development at the ripe stage. This paper examines the potential of P. musarum-induced defences, in the control of anthracnose, the most destructive postharvest disease in banana.

• The Plant Pathology Journal
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• 제31권4호
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• pp.414-420
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• 2015

Antifungal activities of crude extractum of Nanshancha Seed Cake (NSC), to inactivate postharvest pathogens were investigated. Highest inhibitory rate was found against C. musae, C. gloeosporioides and C. papaya P.Henn, which was much stronger than that by tea saponin. Compared to tea saponin, effects of NSC extractum was relatively weak and similar on C. gloeosporioides Penzig and P. italicum. In an in vivo study, best controlling effects by NSC extractum was found with banana anthracnose disease development, which showed no inhibitory effects by tea saponin. NSC extractum controlled in vitro C. musae growth through directly inhibiting germination rate and germ tube elongation, and causing distortation, rupture and indentation of C. musae mycelium. In banana fruit subject to C. musae inoculation, higher PAL, POD, GLU and CHT activity was observed in banana fruit treated with crude NSC extractum than that of water control fruits. Current study proved the best controlling effects of crude NSC extractum in C. musae in vitro and in vivo development, which through direct inhibition of C. musae growth and increasing defense system of the banana fruit.

• The Plant Pathology Journal
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• 제18권3호
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• pp.161-164
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• 2002

Colletotrichum musae was isolated from dark-brown anthracnose lesions on commercial banana (Musa sapientum L.) to establish the causal agent of the symptom. The fungus grew fast and produced white aerial mycelium on PDA. Acervuli developed abundantly on culture plates after incubation for 10 days at $25^{\circ}C$. Pinkish conidial masses were produced on the acervuli, which mostly coalesced together, Conidia were aseptate, hyaline, straight, ellipsoid to globose, and 14.5$\times$6.9 $\mu\textrm{m}$ in size. Black, clavate, round, or irregular-shaped appressoria measuring 8.8$\times$6.8 $\mu\textrm{m}$ were readily formed from germ tubes. Setae-like structures were not found either on the lesion or on the cultures. Sclerotia were also absent. Among the media, PDA medium was the best for mycelial growth. The optimum temperature for mycelial growth was $28^{\circ}C$, while the optimum pH ranged from pH 5.5 to 6.5. The isolates of C musae caused black necrotic lesions on banana fruits by needle-wound inoculation, and orange-colored spore masses were produced on the lesions. The fungus also caused discoloration on apple fruits inoculated.

• The Plant Pathology Journal
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• 제17권6호
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• pp.379.5-380
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• 2001

• The Plant Pathology Journal
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• 제34권6호
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• pp.480-489
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• 2018

Bitter rot caused by Colletotrichum species is a common fruit rotting disease of apple and one of the economically important disease in worldwide. In 2015 and 2016, distinct symptoms of bitter rot disease were observed in apple orchards in five regions of South Korea. In the present study, infected apples from these regions were utilized to obtain eighteen isolates of Colletotrichum spp. These isolates were identified and characterized according to their morphological characteristics and nucleotide sequence data of internal transcribed spacer regions and glyceraldehyde-3-phosphate-dehydrogenase. Molecular analyses suggested that the isolates of Colletotrichum causing the bitter rot disease in South Korea belong to 4 species: C. siamense; C. fructicola; C. fioriniae and C. nymphaeae. C. siamense and C. fructicola belonged to Musae Clade of C. gloeosporioides complex species while C. fioriniae and C. nymphaeae belonged to the Clade 3 and Clade 2 of C. acutatum complex species, respectively. Additionally, we also found that the isolates of C. gloeosporioides species-complex were more aggressive than those in the C. acutatum species complex via pathogenicity tests. Taken together, our results suggest that accurate identification of Colletotrichum spp. within each species complex is required for management of bitter rot disease on apple fruit in South Korea.

• 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.

• 한국균학회지
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• 제37권2호
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• pp.155-160
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• 2009

The production of dihydroxynaphthalene (DHN) melanin is known to be essential factor for pathogenicity in Colletotrichum lagenarium. However, the genetic diversity of melanin genes was not much known among Colletotrichum spp. To investigate the variability of melanin gene in Colletotrichum spp. that cause anthracnose on diverse crops including tomato, we cloned and sequenced partial sd, one of DHN melanin genes encoding for scytalone dehydratase, from eight strains of C. coccodes, C. acutatum, C. truncatum C. caricae, and C. musae. The size of PCR-amplified sd ranged 437 bp to 545 bp. The nucleotide sequence identity of sd among the Colletotrichum strains tested varied from 49% to 99%. All of the PCR-amplified sd from eight strains contain an intron and have two exons coding for 122 amino acids. Overall, the size and nucleotide sequence of sd varied among the five Colletotrichum spp. Sequence identity of the predicted scytalone dehydratase protein of 122 amino acids ranged 50 to 99%. Phylogentic analysis based on the sd nucleotide sequences revealed that the five Colletotrichum spp. could be genetically divided.

• 한국환경농학회지
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• 제29권1호
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• pp.86-91
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• 2010

This study was carried out to assess the antifungal potential of R. oligosporus and its ethyl acetate (EtOAc) extract against the fungal pathogens causing anthracnose disease in apple fruits using disc diffusion, antagonistic effect and morphological abnormalities in fungal mycelia. The percentage of inhibition of antifungal effect of the ethyl acetate extract (5 ${\mu}l$ $disc^{-1}$) of the R. oligosporus against C. acutatum KACC 40848, C. gloeosporioides KACC 40897, C. higginsianum KACC 40806, C. orbiculare KACC 40808, C. coccodes KACC 40008, C. musae KACC 40947, C. boninense KACC 40893, C. liliacearum KACC 40981, C. caudatum KACC 41028 and Colletotrichum sp. KACC 40811 was found to be 44.4, 35.5, 40, 31.1, 33.3, 37.7, 40, 51.1, 28.8 and 28.8%, respectively. Also the fungus R. oligosporus showed potential antagonistic effect of antifungal activity against the tested pathogens of Colletotrichum spp. Further, R. oligosporus had a potential detrimental effect on the morphology of the tested fungi of Colletotrichum spp. such as wrinkle abnormalities, abnormal cell formation, lysis of mycelium, empty cell formation, distorted cell formation and breakage of the mycelium. These findings strongly support the role of R. oligosporus to serve as a potential antifungal agent to control plant pathogenic fungi causing anthracnose disease in apple fruits.

• Mycobiology
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• 제36권2호
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• pp.99-101
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• 2008

The alkaloid securinine was assessed against spore germination of some plant pathogenic and saprophytic fungi (Alternaria alternata, Alternaria brassicae, Alternaria brassicicola, Curvularia lunata, Curvularia maculans, Curvularia pallenscens, Colletotrichum musae, Colletotrichum sp., Erysiphe pisi, Helminthosporium echinoclova, Helminthosporium spiciferum, Heterosporium sp.). Spore germinations of all the tested fungi were inhibited. Alternaria brassicicola, C. lunata, C. pallenscens and H. spiciferum were highly sensitive as complete inhibition of spore germination was observed at very low concentrations (200 ppm).