• Journal of Microbiology and Biotechnology
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• 제29권10호
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• pp.1624-1628
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• 2019

Banana planting altered microbial communities and induced the enrichment of Fusarium oxysporum in rhizosphere compared with that of forest soil. Diseased plant rhizosphere soil (WR) harbored increased pathogen abundance and showed distinct microbial structures from healthy plant rhizosphere soil (HR). The enriched taxon of Bordetella and key taxon of Chaetomium together with some other taxa showed negative associations with pathogen in HR, indicating their importance in pathogen inhibition. Furthermore, a more stable microbiota was observed in HR than in WR. Taken together, the lower pathogen abundance, specific beneficial microbial taxa and stable microbiota contributed to disease suppression.

• The Plant Pathology Journal
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• 제17권6호
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• pp.362.4-362
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• 2001

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1999년도 임시총회 및 추계 학술발표회
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• pp.30.2-30
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• 1999

• The Plant Pathology Journal
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• 제25권4호
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• pp.352-360
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• 2009

The potential of three plants extracts, to protect potato plants against bacterial wilt caused by Ralstonia solanacearum was determined under greenhouse and field conditions. All soil drenching treatments of aqueous plant extracts of Hibsicus sabdariffa, Punica granatum and Eucalyptus globulus significantly reduced the disease severity compared with inoculated control. Although the applications of all three plant extracts resulted in similar reductions of disease severity in field up 63.23 to 68.39%, treatment of E. globulus leaf extract was found greater in restricting the symptom development than other the two plant extracts in the greenhouse. More than 94% reduction in the bacterial wilt symptom was observed in potato plants. All tested plant extracts were effective in inhibiting the growth of bacterial pathogen, not only in vitro, but also in stem of potato plants as compared with the inoculated control Potato plants treated with extract of H. sabdariffa reduced bacterial growth more effectively than treatment with P. granatum and E. globulus. Activity of defence-related enzymes, including peroxidase, polyphenoloxidase and phenylalanine ammonia lyase, were significantly increased in plants treated with the plant extracts compared to the control during the experimental period. In general, the higher enzymes activities were determined in both inoculated and non-inoculated treated potato plants after 8 days from plant extracts treatment. These results suggested that these plant extracts may be play an important role in controlling the potato bacterial wilt disease, through they have antimicrobial activity and induction of systemic resistance in potato plants.

• The Plant Pathology Journal
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• 제35권6호
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• pp.598-608
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• 2019

Endophytic fungi have received much attention as plant growth promoters as well as biological control agents against many plant pathogens. In this study, 30 endophytic fungal species, isolated from various plants in China, were evaluated using in vitro dual culture assay against Fusarium oxysporum f. sp. cucumerinum, causing wilt in cucumber. The results of the present study clearly showed that all the 30 endophytic fungal isolates were highly capable of inhibiting the mycelial colony growth of Fusarium oxysporum f. sp. cucumerinum with inhibition % over 66% as compared to control treatments. Among all of them, 5 isolates were highly effective such as, Penicillium sp., Guignardia mangiferae, Hypocrea sp., Neurospora sp., Eupenicillium javanicum, and Lasiodiplodia theobromae, respectively. The Penicillium sp. and Hypocrea sp. were highly effective as compared to other isolates. From in vitro results 10 best isolates were selected for greenhouse studies. The results of the greenhouse studies showed that among all of them 3 endophytic fungal isolates successfully suppressed wilt severity when co-inoculation with pathogen Fusarium. oxysporum f. sp. cucumerinum. The endophytic fungi also enhanced plant growth parameters of the host plants, the antagonistic fungal isolates increased over all plant height, aerial fresh, and dry weight as compared to control.

• The Plant Pathology Journal
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• 제39권5호
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• pp.430-448
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• 2023

Recently, strategies for controlling Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of Fusarium wilt of tomato, focus on using effective biocontrol agents. In this study, an analysis of the biocontrol and plant growth promoting (PGP) attributes of 11 isolates of loamy soil Bacillus spp. has been conducted. Among them, the isolates B.PNR1 and B.PNR2 inhibited the mycelial growth of Fol by inducing abnormal fungal cell wall structures and cell wall collapse. Moreover, broad-spectrum activity against four other plant pathogenic fungi, F. oxysporum f. sp. cubense race 1 (Foc), Sclerotium rolfsii, Colletotrichum musae, and C. gloeosporioides were noted for these isolates. These two Bacillus isolates produced indole acetic acid, phosphate solubilization enzymes, and amylolytic and cellulolytic enzymes. In the pot experiment, the culture filtrate from B.PNR1 showed greater inhibition of the fungal pathogens and significantly promoted the growth of tomato plants more than those of the other treatments. Isolate B.PNR1, the best biocontrol and PGP, was identified as Bacillus stercoris by its 16S rRNA gene sequence and whole genome sequencing analysis (WGS). The WGS, through genome mining, confirmed that the B.PNR1 genome contained genes/gene cluster of a nonribosomal peptide synthetase/polyketide synthase, such as fengycin, surfactin, bacillaene, subtilosin A, bacilysin, and bacillibactin, which are involved in antagonistic and PGP activities. Therefore, our finding demonstrates the effectiveness of B. stercoris strain B.PNR1 as an antagonist and for plant growth promotion, highlighting the use of this microorganism as a biocontrol agent against the Fusarium wilt pathogen and PGP abilities in tomatoes.

• 농약과학회지
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• 제10권4호
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• pp.313-319
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• 2006

강원도 춘천시 신북읍의 토마토 풋마름병이 다발생한 포장으로부터 건전한 토마토 뿌리를 채취하여 약 200개의 미생물을 선발하였다. 선발된 미생물들에 대한 저지원 테스트를 실시한 결과, 풋마름병원균 (Ralstonia solanacearum)에 항균 효과를 나타냈으며 그 중 가장 우수한 항균 효과를 나타낸 KPB3 균주를 선발하여 생리 생화학적 특성조사 와 16S rRNA 유전자 분석을 실시하여 Paenibacillus spp. 균으로 동정하였다. KPB3균주의 활성적 우수성을 확인하기 위하여, 먼저 포트 실험에서 KPB3 균주를 토양 관주처리 결과 무처리구에 비하여 처리구의 방제효과가 66.7% 뛰어난 것을 확인하였다. 또한 토마토 포장에서의 방제효과 시험은 2006년 봄과 가을에 2회 실시하였으며, 전반적으로 풋마름병 발생은 가을보다 봄에 높은 발병율을 나타내었다. 그 결과, KPB3 균주 처리구에서 봄과 가을 각각 50%와 60% 이상 방제 효과를 나타내어 KPB3 균주는 토마토 풋마름병 억제용 생물 제제로서의 개발 가능성이 있음을 확인하였다.

• 식물병연구
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• 제19권2호
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• pp.108-113
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• 2013

Ralstonia solanacearum에 의한 시들음 피해는 고온기 재배가 증가함에 따라 피해가 증가하고 있다. 이에 재배적 방법으로 토마토대목을 이용하고 있으나 병이 다 발생하는 지역에서는 효과가 기대에 미치지 못한다. 이에 따라서 AVRDC에서 수집한 풋마름병 저항성 가지 대목인 EG203을 재료로 하여 풋마름병 다 발생포장인 부여 토마토시험장 비닐하우스에서 2003-2005년, 구미시 비닐하우스에서 2009-2011년까지 두 곳에서 각각 3년간 실시하였다. EG203(가지)는 광발아 종자로 파종 시 육묘 트레이에 직접 파종하여야 하며 EG-203(가지)의 파종 적기는 토마토 접수보다 3주전에 파종해야 접수와 비슷한 경경(2.5-3.0 mm)에 도달하여 접목하기에 알맞았다. 접목방법은 맞접과 삽접이 93-96%의 활착률을 보여 대목으로 사용가능한 것으로 확인되었다. 접목 후 포장에 정식한 후의 풋마름병 발생을 2003년부터 2005년까지 3년 동안의 평균은 EG203(가지) 접목 시 4.3%로 실생의 58.0%보다 매우 낮았으며 대목용 품종의 25.0-36.7%보다도 낮게 나타났다. 구미에서 2009년부터 2011년까지 3년간 대목 효과에 대하여 시험한 결과는 2009년 5농가에서 EG203과 실생묘를 비교한 결과 EG203에서는 풋마름병 발생률이 2-5%였으나 실생은 20-80%를 보였다. 2010년에는 토마토대목('B-blocking', '청강')과 가지대목(EG203)을 갖고 비교 한 결과 풋마름병 발생률의 차이는 보이지 않았으나 가지대목(EG203)에서 복화방 출현이 늦어 수확이 감소되는 경향을 보였다. 2011년 토마토대목('청강')과 가지대목(EG203)으로 3농가에서 시험한 결과 토마토대목('청강')에서 풋마름병 발생률은 60-85%, 가지대목(EG203)은 0-1%로 가지대목에서 병발생률이 매우 낮았다. 가지대목(EG203)을 이용할 경우 토마토대목과 비교 복화방이 늦게 발생하여 토마토 생산량이 줄었다. 따라서 병 발생이 낮은 곳에서는 토마토대목을 활용하여 접목을 하고 병이 다 발생하는 지역에서는 가지대목(EG203)을 활용하는 것이 재배에 유리하다고 판단되어진다.

• 식물병연구
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• 제20권4호
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• pp.245-252
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• 2014

본 실험은 Fusarium oxysporum f. sp. cucumerinum에 의해 발생하는 오이 덩굴쪼김병의 효율적인 저항성 검정 방법을 확립하기 위하여 수행되었다. ITS와 TEF 유전자 염기서열 분석과 멜론, 참외, 오이 및 수박을 포함한 박과 작물에 대한 기주 특이성 분석을 통해 KR5 균주를 F. oxysporum f. sp. cucumerinum으로 동정하였다. 그리고 덩굴쪼김병균 KR5에 저항성 정도가 다른 오이 네 품종과 오이용 대목 두 품종을 선발하여 유묘의 생육 시기, 뿌리 상처, 접종원 농도 및 접종 후 재배 온도에 따라 이들 여섯 품종의 덩굴쪼김병 발생을 조사하였다. 저항성 품종의 덩굴쪼김병 발병도는 접종 후 재배 온도에 따라 차이를 나타냈으며, 저항성 품종들은 접종 후에 $20^{\circ}C$보다 $25^{\circ}C$나 $30^{\circ}C$에서 재배하였을 때 높은 저항성을 보였다. 그리고 유묘의 생육 시기 중 파종 후 7일된 유묘에 덩굴쪼김병균을 접종하였을 때 가장 큰 저항성과 감수성 차이를 나타내었다. 이상의 결과로부터 오이 덩굴쪼김병에 대한 저항성을 효과적으로 검정하는 방법으로 파종하고 7일 동안 재배한 유묘의 뿌리로부터 흙을 제거하고, 이들을 $1.0{\times}10^6-1.0{\times}10^7$ conidia/ml 농도의 F. oxysporum f. sp. cucumerinum 포자현탁액에 침지하여 접종한 후에 건전한 원예용 상토에 이식하고 $25^{\circ}C$ 생육상에서 3주간 재배하는 방법을 제안한다.

• The Plant Pathology Journal
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• 제18권5호
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• pp.293-299
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• 2002

A survey of Fusarium wilt of perilla was conducted in 12 locations in Korea from 1999 to 2001. The disease occurred in 74 out of 187 fields in the 12 locations surveyed, and incidence of the disease reached up to 30% at its maximum in some perilla fields in Seosan and Dangjin. Incidence of the disease in the other locations ranged from 0.2 to 20%. A total of 327 isolates of Fusarium spp. were obtained from stems and roots of the diseased perilla plants. The isolates were identified based on their morphological characteristics. Out of the 327 isolates of Fusarium, 277 isolates from 12 locations were identified as F. oxysporum, 11 isolates from three locations as F. solani,17 isolates from two locations as F. equiseti, 4 isolates from one location as F. avenaceum and 6 isolates from one location as F. subglutinans. The other 12 isolates of Fusarium from four locations were unidentified. Twelve isolates of F. oxysporum and two isolates each of the other Fusarium spp. were tested for their pathogenicity to five cultivars of perilla. Seven isolates of F. oxysporum were strongly pathogenic to some perilla cultivars, but the other five isolates were weakly or not pathogenic. One isolate of F. solani was strongly pathogenic to all the perilla cultivars tested, but another isolate was not pathogenic. All the isolates of F. equiseti, F. avenaceum, and F. Subglutinans tested were not pathogenic to any of the perilla cultivars tested. Symptoms on the perilla plants induced by artificial inoculation with strongly pathogenic isolates of F. oxysporum and F. solani appeared as wilt, stem blight, and root yet, which were similar to those observed in the fields. The isolates which induced symptoms by artificial inoculation were re-isolated from the lesions of the perilla plants inoculated. All the isolates of F. oxysporum tested were not pathogenic to eight other crops inoculated. Results of this study reveal that F. oxysporum is the main pathogen of perilla wilt and that it is host specific to perilla. forma specialis of F. oxysporum causing wilt of perilla is proposed as perillae.