• The Plant Pathology Journal
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• 제17권1호
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• pp.52-56
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• 2001

This study was undertaken to separate and identify antifungla substances produced by Gilocladium virens G1, a biocontrol agent used for the control of plant diseases caused by Rhizoctonea solani. The culture of G. virens G1 effectively inhibited the growth of R. solani, Colletotrichum gloeosporioides, and Phytophthora capsici, but less that of Fusarium oxysporum. The n-hexane extract of the G. virens culture, which was used for the purification of responsible substances, strongly inhibited R. solani and C. gloeosporioides, but not P. capsici, although the n-butanol extract was effective on all of the pathogens tested. An antifungal substance was purified using the n-hexane extract by Silica gel column chromatography and HPLC. The substance was examined for purity by HPLC and for nature by UV spectrometry, which differed from known antibiotic compounds such as gliotoxin, viridin and gliovirin. The antifungal substance was very liphophilic based on its solvent-solubility and Rf values on TLC, and more inhibitory to C. gloeosporioides than other fungal pathogens tested.

• Journal of Microbiology and Biotechnology
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• 제20권1호
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• pp.138-145
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• 2010

A bacterial strain isolated from soil for its potential to control the anthracnose disease caused by Colletotrichum gloeosporioides was identified as a Bacillus subtilis. Bacillus subtilis CMB32 produced antifungal agents on M9 broth at $30^{\circ}C$. Biosurfactant lipopeptides produced by Bacillus subtilis CMB32 were precipitated by adjusting to pH 2 and extracting using chloroform/methanol, and then were purified using column chromatography and reverse-phase HPLC. The molecular masses of the lipopeptides were estimated by MALDI-TOF mass spectrometry as (a) 1,080, (b) 1,486, and (c) 1,044 Da, respectively. They had cyclic structures and amino acid compositions of (a) Pro, Asx, Ser, Tyr, Glx, (b) Glx, Tyr, Thr, Ala, Pro, lie, and (c) Glx, Leu, Val, Asx, respectively. Further analysis revealed that Bacillus subtilis CMB32 produced three antifungal lipopeptides: (a) iturin A, (b) fengycin, and (c) surfactin A.

• 식물병과 농업
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• 제5권1호
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• pp.8-13
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• 1999

Twenty two different disease on strawberry have been reported in Korea. Their occurrence patterns were depended on the varieties cultivated. Fusarium wilt occurred seriously on var. Hokowase, a variety used for the fields or semi-forcing culture. In recent years, however, anthracnose occurred remarkably as the acreage of forcing culture increases. Consequently, anthracnose reduced the stand rate and yield of the strawberry. Average occurrence rate of anthracnose was 36.9% on major strawberry cropping areas. Nyoho and Akihime, which are popular varieties for the forcing culture, are considered to be susceptible, but Holiwase and Suhong are resistant against this disease. Colletotrichum gloeosporioides and Glomerella cingulata have been reported as casual agents for this disease in Korea. C. gloeosporoides was recently reported, but C. fragariae, known to be a strong pathogen in foreign countries, has bot been found yet in Korea. These two fungal pathogens showed significant differences in some characteristics such as major infection parts of plant and responses to temperatures as well as benomyl resistance. In addition, C. gloeosporioides is more pathogenic than G. cingulata. Because vinly sheltering is effective for control of anthracnose to protect water disposal of the pathogen during the seedling stages, it is strongly recommend to use this method in conjunction with integrated control programs.

• The Plant Pathology Journal
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• 제31권3호
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• pp.269-277
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• 2015

Anthracnose caused by Colletotrichum gloeosporioides has been destructive during pepper fruit production in outdoor fields in Korea. In vitro antifungal activities of 15 different plant essential oils or its components were evaluated during conidial germination and mycelial growth of C. gloeosporioides. In vitro conidial germination was most drastically inhibited by vapour treatments with carvacrol, cinnamon oil, trans-cinnamaldehyde, citral, p-cymene and linalool. Inhibition of the mycelial growth by indirect vapour treatment with essential oils was also demonstrated compared with untreated control. Carvacrol, cinnamon oil, trans-cinnamaldehyde, citral and eugenol were among the most inhibitory plant essential oils by the indirect antifungal efficacies. Plant protection efficacies of the plant essential oils were demonstrated by reduced lesion diameter on the C. gloeosporioides-inoculated immature green pepper fruits compared to the inoculated control fruits without any plant essential oil treatment. In planta test showed that all plant essential oils tested in this study demonstrated plant protection efficacies against pepper fruit anthracnose with similar levels. Thus, application of different plant essential oils can be used for ecofriendly disease management of anthracnose during pepper fruit production.

• The Plant Pathology Journal
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• 제40권1호
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• pp.16-29
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• 2024

The Colletotrichum gloeosporioides species complex includes many phytopathogenic species, causing anthracnose disease on a wide range of host plants and appearing to be globally distributed. Seventy-one Colletotrichum isolates in the complex from different plants and geographic regions in Korea were preserved in the Korean Agricultural Culture Collection (KACC). Most of them had been identified based on hosts and morphological features, this could lead to inaccurate species names. Therefore, the KACC isolates were re-identified using DNA sequence analyses of six loci, comprising internal transcribed spacer, gapdh, chs-1, his3, act, and tub2 in this study. Based on the combined phylogenetic analysis, KACC strains were assigned to 12 known species and three new species candidates. The detected species are C. siamense (n = 20), C. fructicola (n = 19), C. gloeosporioides (n = 9), C. aenigma (n = 5), C. camelliae (n = 3), C. temperatum (n = 3), C. musae (n = 2), C. theobromicola (n = 2), C. viniferum (n = 2), C. alatae (n = 1), C. jiangxiense (n = 1), and C. yulongense (n = 1). Of these, C. jiangxiense, C. temperatum, C. theobromicola and C. yulongense are unrecorded species in Korea. Host plant comparisons showed that 27 fungus-host associations are newly reported in the country. However, plant-fungus interactions need to be investigated by pathogenicity tests.

• The Plant Pathology Journal
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• 제20권4호
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• pp.247-251
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• 2004

We developed a polyclonal antibody (PAh) based- ELISA system to accurately and rapidly monitor inocula on plant surface before onset of anthracnose. Titer of mouse antisera against conidia of Colletotrichum gloeosporioides was determined by using indirect ELISA. It was high enough to be detectable up to ${\times}$ 12,800 dilutions. Absorbance readings exceeded (1.5even at a 10$^{-5}$ dilution. Sensitivity of PAb was precise enough to detect spore concentration as low as 50 conidia/well by indirect ELISA. PAb1 and PAb2 proved to be very sensitive and highly specific to the target pathogen, C. gloeosporioides, apparently discriminating other unrelated pathogens, or epiphytes. Absorbance values for original isolate exceeded 1.0, but no reaction was detected with other isolates, except three other anthracnose fungi: C. gloeosporioides (pepper strain), Glomerella cingulata (apple strain) and C. lagenarium. Our data suggest that PAb1 and PAb2 bind with the protein epitope that partially contains residues of amino acid, arginine, and Iysine. This kit fulfills the require-ments for detecting inoculums before infection and during onset of anthracnose on sweet persimmon.

• The Plant Pathology Journal
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• 제33권6호
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• pp.572-581
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• 2017

Anthracnose of papaya fruit caused by the fungus Colletotrichum gloeosporioides is one of the most economically important postharvest diseases. Hot water immersion (HW) and calcium chloride (Ca) treatments have been used to control papaya postharvest diseases; however, the effect of the combination HW-Ca on the pathogen growth and the development of the disease in infected papaya fruit has been scarcely studied. The aim of this study was to evaluate the effect of the HW-Ca treatment on the in vitro growth of C. gloesporioides conidia and the quality of infected papaya. In vitro, the HW-Ca treated conidia showed reduced mycelial growth and germination. In vivo, the HW-Ca treatment of infected papaya delayed for 5 days the onset of the anthracnose symptoms and improved the papaya postharvest quality. The combined treatment HW-Ca was better than any of the individual treatments to inhibit the in vitro development of C. gloeosporioides and to reduce the negative effects of papaya anthracnose.

• The Plant Pathology Journal
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• 제20권4호
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• pp.252-257
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• 2004

We developed a polyclonal antibody based-ELISA system to monitor inocula accurately and rapidly before onset of anthracnose on soybean sprouts. Titer of mouse antisera against conidia of Colletotrichum gloeosporioides, determined by indirect ELISA, was high enough to be detectable up to ${\times}$25,600 dilutions. Both PAb1 and PAb2 had the highest level of reactivity to Colletotrichum gloeosporioides. Absorbance readings exceeded 0.15. Sensitivity of PAb to C. gloeosporioides was precise enough to detect spore concentration as low as 500 conidia/well by indirect ELISA. Both antibodies are very sensitive and highly specific to the target pathogen Colletotrichum gloeosporioides, apparently discriminating other unrelated pathogen, or epiphytes. This kit fulfills the requirements far detecting inocula before infection and onset of anthracnose. Our ELISA system should also be feasible to detect C. acutatum (Mungbean sprouts rot) and G. cingulata (C. gleosporioides), (apple, pepper). It was remarkable that absorbance value was not reduced even after 4 consecutive washings (Fig.4), suggesting that antigenic determinants are on the surface of conidia. Antigenic determinant was characterized by heating and enzyme treatment: Both PAb1 and PAb2 bind to protein epitope that does not contain residue of amino acid, arginine, and Iysine, even though more work needs to be done.

• The Plant Pathology Journal
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• 제19권6호
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• pp.269-273
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• 2003

A total of 57 isolates of Colletotrichum gloeosporioides were recovered from diseased tissues of Hall's crab apple (Malus haliana), 3 cultivars of edible apple (M. pumila var. dulcissima), red pepper (Capsicum annum), and grapevine (Vitis vinifera) fruits. All isolates showed strong virulence on their own host plants. Isolates from edible apple exhibited high level of cultivar specificity in pathogenicity tests. Ten isolates from apple cultivar 'Fuji' were virulent on 'Jonathan' and 'Rall's Genet'. However, 12 isolates from 'Jonathan' and 'Rall's Genet' were not virulent on 'Fuji'. Among the 24 isolates from red pepper, only seven and two isolates were infective on edible apple and grapevine fruits, respectively. All six isolates from grapevine were only virulent on their own host. These isolates were grouped into five vegetative compatibility groups (VCGs), A, B, C, D, and E, by demonstrating heterokaryosis through complementation using nitrate-nonutilizing (nit) mutants. Among them, isolates belong to VCG-A and VCG-D accounted for 24 and 17 isolates； those in VCG-A exhibited wide host range involving Hall's crab apple, all three edible apple cultivars, and red pepper. On the other hand, isolates of VCG-D and VCG-E showed limited host range specific to red pepper and grapevine, respectively. Taken together, the data suggest that among C. gloeosporioides isolates, the concepts of pathotype and/or forma specialis may exist, and that three is a relationship between host specificity and VCG grouping among C. gloeosporioides isolates.

• 한국균학회지
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• 제33권1호
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• pp.35-37
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• 2005

2002년부터 2003년까지 2년 동안 경남 거제시 학동면 조팝나무 재배농가에서 잎과 줄기에 이상증상이 심하게 발생하였다. 병징은 처음 잎에 암적갈색의 작은 둥근 반점이 많이 생기고, 줄기에 검은색 반점이 나타나며 진전됨에 따라 약간 움푹하게 들어가고 긴 타원형으로 검게 썩는다. 심하게 발생하면 병든 가지 윗부분은 말라 죽는다. 균총은 PDA배지에서 회색이고 분생포자 모양은 단세포, 원통형이며 크기는 $6{\sim}12{\times}3{\sim}5\;{\mu}m$였다. 강모의 색깔은 암갈색이고 바늘모양의 원추형이며 크기는 $23{\sim}42{\times}2{\sim}4\;{\mu}m$이었다. 균사생육 최적온도는 $30^{\circ}C$였다. 분리된 병원균으로 병원성을 검정한 결과, 자연 감염된 병징과 똑같았다. 이상의 결과를 가지고 본 병해를 Colletotrichum gloeosporioides에 의한 조팝나무 탄저병으로 명명할 것을 제안한다.