• Mycobiology
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• 제50권6호
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• pp.467-474
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• 2022

Autophagy serves as a survival mechanism and plays important role in nutrient recycling under conditions of starvation, nutrient storage, ad differentiation of plant pathogenic fungi. However, autophagy-related genes have not been investigated in Colletotrichum scovillei, a causal agent of pepper fruit anthracnose disease. ATG8 is involved in autophagosome formation and is considered a marker of autophagy. Therefore, we generated an ATG8 deletion mutant, ΔCsatg8, via homologous recombination to determine the functional roles of CsATG8 in the development and virulence of C. scovillei. Compared with the wild-type, the deletion mutant ΔCsatg8 exhibited a severe reduction in conidiation. Conidia produced by ΔCsatg8 were defective in survival, conidial germination, and appressorium formation. Moreover, conidia of ΔCsatg8 showed reduced lipid amount and PTS1 selectivity. A virulence assay showed that anthracnose development on pepper fruits was reduced in ΔCsatg8. Taken together, our results suggest that CsATG8 plays various roles in conidium production and associated development, and virulence in C. scovillei.

• 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.

• 식물병연구
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• 제26권3호
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• pp.190-193
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• 2020

강원도 강릉시 사천면 비닐하우스에서 재배중인 호박 과실에 탄저병이 발생하였다. 병든 호박 과실에 분홍색의 분생포자 층이 동심원으로 나타나 점차 확대되어 과실이 무르는 증상을 나타내었다. 원인균을 규명하기 위하여 순수 분리 후 균학적 특성 및 ITS, GAPDH, CHS-1, HIS3, ACT, TUB2 염기서열 분석결과 Colletotrichum fioriniae로 동정하였다. 또한, 병원성이 확인되었고 접종시험에서 동일한 균이 반복적으로 분리되었다. 따라서, 이러한 결과를 바탕으로 C. fioriniae에 의한 호박 과실에 발생하는 탄저병의 발생을 국내 처음으로 보고한다.

• 한국균학회지
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• 제25권1호통권80호
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• pp.30-34
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• 1997

온주밀감의 병든 잎으로부터 분리된 분생포자세대와 병들어 죽은 가지로부터 분리된 유성세대의 형태학적 특정을 토대로 감귤 탄저병의 병원균은 Glomerella cingulata(분생포자 세대 Colletotrichum gloeosporioides)로 분리 동정되었다. 감귤 탄저병균은 온주밀감, 유자, 하귤 등의 잎에 상처 접종에 의해서 감염을 일으켰고, 균사 생장 및 분생포자 형성의 적온은 각각 $25{\sim}30^{\circ}C$범위였다. 잎과 가지에서 분리된 감귤 탄저병균의 균총의 생장 속도와 색, 분생포자와 부착기의 형태와 크기 등과 같은 특징들은 감귤류 저장병에 관여하는 FGG strain의 특징과 유사하였지만, 일부 형태 및 병원학적 특징이 FGG strain과 일치하지 않아 다른 strain일 가능성도 배제할 수 없다.

• 식물병연구
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• 제21권1호
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• pp.6-11
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• 2015

고추 탄저병 요방제 수준을 설정하기 이하여 시험한 결과 노지 고추 수량에 영향을 주지 않는 수준의 탄저병 방제적기는 발생정도가 0.9% 이하이었으며, 노지고추 탄저병 발생정도와 수량과의 회귀식은 Y = -16.83X + 327.57, $R^2=0.83$ 성립하였다. 비가림 재배(무강우 조건) 고추의 수량에 영향을 주지 않는 수준의 탄저병 방제적기는 발생정도가 1.7% 이하이었으며, 고추탄저병 발생정도와 수량과의 회귀식은 Y = -4.92X + 361.02, $R^2=0.84$ 성립하였다. 비가림 재배(강우 조건) 고추의 수량에 영향을 주지 않는 수준의 탄저병 방제적기는 발생정도가 2.3% 이하이었으며, 고추 탄저병 발생정도와 수량과의 회귀식은 Y =-5.91X + 359.71, $R^2=0.76$ 성립하였다.

• The Plant Pathology Journal
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• 제26권3호
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• pp.273-279
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• 2010

We evaluated 209 Capsicum accessions from the National Agrobiodiversity of RDA, for their reaction against of anthracnose disease caused by Colletotrichum acutatum. Two hundred nine accessions of Capsicum were almost composed with Capsicum annuum var. annuum originated from 37 countries. The percentage of infection due to C. acutatum ranged from 11.1% to 100% on immature and matured pepper fruits at 21 days after inoculation. On immature fruits of pepper, one hundred seventy three accessions of tested pepper were found infected with C. acutatum. Out of the 173 accessions, eighty five accessions were susceptible to anthracnose with dark brown to black lesions and slowly increased in size at 21 days after inoculation. Only thirty six accessions showed resistance against C. acutatum. On mature fruits of pepper, one hundred ninety eight accessions were infected with C. acutatum at 21 days after inoculation. Twenty one accessions showed a resistance reaction against C. acutatum. The results of this work indicated that all of resistance accessions to C. acutatum were have a genetic potential for the resources of resistance can be further used in pepper breeding programme against anthracnose and also demand more detailed investigation in this.

• The Plant Pathology Journal
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• 제35권6호
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• pp.575-584
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• 2019

Colletotrichum acutatum is a species complex responsible for anthracnose disease in a wide range of host plants. Strain C. acutatum KC05, which was previously isolated from an infected pepper in Gangwon Province of South Korea, was reidentified as C. scovillei using combined sequence analyses of multiple genes. As a prerequisite for understanding the pathogenic development of the pepper anthracnose pathogen, we optimized the transformation system of C. scovillei KC05. Protoplast generation from young hyphae of KC05 was optimal in an enzymatic digestion using a combined treatment of 2% lysing enzyme and 0.8% driselase in 1 M NH₄Cl for 3 h incubation. Prolonged incubation for more than 3 h decreased protoplast yields. Protoplast growth of KC05 was completely inhibited for 4 days on regeneration media containing 200 ㎍/ml hygromycin B, indicating the viability of this antibiotic as a selection marker. To evaluate transformation efficiency, we tested polyethylene glycol-mediated protoplast transformation of KC05 using 19 different loci found throughout 10 (of 27) scaffolds, covering approximately 84.1% of the entire genome. PCR screening showed that the average transformation efficiency was about 17.1% per 100 colonies. Southern blot analyses revealed that at least one transformant per locus had single copy integration of PCR-screened positive transformants. Our results provide valuable information for a functional genomics approach to the pepper anthracnose pathogen C. scovillei.

• 식물병연구
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• 제8권4호
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• pp.228-233
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• 2002

딸기육묘시 발생하는 탄저병의 1차 전염원을 밝히기 위해 본 시험을 수행한 결과, 육묘포의 토양과 주변 잡초중에는 탄저병균이 검출되지 않았으나 외관상 건전한 딸기의 모주를 습실처리하였을 경우에는 탄저병균이 검출되었다. 딸기묘에 탄저병균의 포자현탁액을 분무접종하였을때 발병은 되지 않았지만 습실처리하였을 경우, 접종 17일 후까지 발병이 되었고, 포자현탁액을 분무접종한 딸기잎을 주사전자현미경으로 관찰하였을 때 접종 7일 후 부착기만 관찰되었다 그러므로 딸기 탄저병은 육묘상에서 딸기 모주를 통해 전염이 되고, 탄저병균의 포자가 모주에 부착되어 있더라도 부적당한 환경조건에 의해 발병되지 않아 육안으로 판별이 불가능하며, 발아가 되었으나 침입이 완전히 이루어지지 않은 경우 부착기로 남아 침입을 시도하는 것으로 생각된다.

• 식물병연구
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• 제8권2호
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• pp.120-123
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• 2002

고추 탄저병 발생 상황을 알아보기 위하여 경북 북부 지방의 예천, 안동, 의성, 청송, 영양, 봉화 등 6개 시군 고추 주산지에서 포장 조사한 결과, 본포에서 6월부터 발병이 시작되어 9월 중순에는 약 30%로 급증하였다. 고추 탄저병이 인접과실로 전염하는 데는 보통 2-3일이 소요되었으며, 5-7일 후에 만연되는 것을 확인할 수 있었다. 과실에 탄저병을 일으키는 병원균은 대부분 Colletotrichum gloeosporioides였다. 고추 탄저병 발생에 관여하는 요인은 무엇보다도 이병 잔재물과 연작에 의한 1차 전염원의 증가, 생육기의 강우일수와 그 지속기간 등 기상 요인들이 복합적으로 관여함을 알 수 있었다. 병 발생을 줄이기 위해서는 이병 잔재물의 월동전 처리와 타 작물과의 윤작, 비가림 재배, 예방 위주의 약제 살포가 필요하다고 본다.

• The Plant Pathology Journal
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• 제31권2호
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• pp.165-175
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• 2015

Anthracnose is a fungal disease caused by Colletotrichum species that is detrimental to numerous plant species. Anthracnose control with fungicides has both human health and environmental safety implications. Despite increasing public concerns, fungicide use will continue in the absence of viable alternatives. There have been relatively less efforts to search antagonistic bacteria from mudflats harboring microbial diversity. A total of 420 bacterial strains were isolated from mudflats near the western sea of South Korea. Five bacterial strains, LB01, LB14, HM03, HM17, and LB15, were characterized as having antifungal properties in the presence of C. acutatum and C. gloeosporioides. The three Bacillus atrophaeus strains, LB14, HM03, and HM17, produced large quantities of chitinase and protease enzymes, whereas the B. amyloliquefaciens strain LB01 produced protease and cellulase enzymes. Two important antagonistic traits, siderophore production and solubilization of insoluble phosphate, were observed in the three B. atrophaeus strains. Analyses of disease suppression revealed that LB14 was most effective for suppressing the incidence of anthracnose symptoms on pepper fruits. LB14 produced antagonistic compounds and suppressed conidial germination of C. acutatum and C. gloeosporioides. The results from the present study will provide a basis for developing a reliable alternative to fungicides for anthracnose control.