• The Plant Pathology Journal
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• 제21권4호
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• pp.406-408
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• 2005

Web blight symptoms were frequently observed on soybean plants grown in a farmer's fields located in Jincheon in Korea during a disease survey in August, 2005. Incidence of the disease was $5-20\%$ infected plants in two of four soybean fields investigated. A total of 31 isolates of Rhizoctonia sp. were obtained from leaves, leaf petioles, and pods of diseased soybean plants. The isolates were identified as Rhizoctonia solani AG-l(IA) by anastomosis test and based on the morphological and cultural characteristics. Three isolates of R. solani AG-l(IA) were tested for pathogenicity to five cultivars of soybean by artificial inoculation. All the isolates induced blight symptoms on the leaves of soybean and formed sclerotia on the lesions, which were similar to those observed in the field. The pathogenicity tests revealed that all the soybean cultivars tested were susceptible to the pathogen. There was no difference in the pathogenicity among the isolates. The present study first reveals that R. solani AG-l(IA) causes web blight of soybean in Korea.

• 한국식물병리학회지
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• 제10권1호
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• pp.7-12
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• 1994

Incidence of radish disease caused by Rhizoctonia solani ranged from 1 to 30% in fields located at Hwaseong, Naju and Yeoncheon in Korea during the growing seasons in 1989, 1990 ad 1993. A total of 133 isolates of R. solani was obtained from the diseased seedlings, leaves and roots of radish collected. The fungus was most commonly isolated from the roots. Among 133 isolates of R. solani, 56 isolates were classified as anastomosis group AG-1 by anastomosis test, 37 isolates as AG-2-1, and 40 isolates as AG-4. Among the isolates of AG-1, 26 isolates were grouped as cultural type IA, and the others as cultural type IB. Cultural types IA and IB of AG-1, were isolated from the leaves, AG-2-1 from the roots, and AG-4 from the seedlings, leaves and roots. Pathogenicity tests revealed that the AG-1(IA) isolates were highly virulent on leaves of radish, but avirulent on the seedlings, petioles and roots. The AG-1(IB) isolates were highly virulent on the leaves, but mildly virulent on the seedlings and avirulent or mildly virulent on the petioles and roots. The AG-2-1, isolates were mildly virulent on the leaves and seedlings and mildly or highly virulent on the petioles and roots. The AG-4 isolates were highly virulent on the seedlings and mildly or highly virulent on the leaves, petioles and roots.

• 식물병연구
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• 제28권1호
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• pp.51-53
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• 2022

In January 2021, unusual outbreak of shoot rot symptoms was observed in young spikenard (Aralia cordata) plants growing in vinyl greenhouses located in Chuncheon and Yanggu, Gangwon Province, Korea. The symptoms initially appeared on young shoots of the plants at or above the soil surface level. Later, the infected shoots wholly rotted and blighted. The incidence of diseased plants in the vinyl greenhouses investigated ranged from 5% to 30%. Eight isolates of Rhizoctonia sp. were obtained from shoot lesions of the diseased plants. All the isolates were identified as Rhizoctonia solani AG-2-1 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-2-1 were tested for pathogenicity on young shoots of spikenard plants using artificial inoculation. All the tested isolates induced shoot rot symptoms on the inoculated plants. The symptoms were similar to those observed in spikenard plants from the vinyl greenhouses investigated. This is the first report of R. solani AG-2-1 causing shoot rot in spikenard.

• 한국균학회지
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• 제20권1호
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• pp.44-50
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• 1992

Rhizoctonia solani의 균사융합군(AG) 중에서 생장속도가 빠른 AG-1과 AG-4는 가장 많은 원형질체를 형성하였으며 속도가 느린 AG-3은 저조하였고 중간인 AG-2와 AG-5는 또한 중간이었다. 균핵의 형성은 AG에 따라 차이가 있었다. Cellulase "onozuka" R-l0, macerozyme R-10, ${\beta}-glucuronidase$의 효소 복합액에서 가장 많은 원형질체를 형성하였다. 5개 융합군은 30시간 배양한 3g의 균사를 0.6 M mannitol이 첨가된 효소 복합액에 $32^{\circ}C$에서 3-4시간 처리하면 가장 많은 원형질체를 형성하였다. 균핵을 형성하는 AG-1을 열처리로 불활성화시킨 후 균핵을 형성하지 않는 AG-5의 원형질체를 PEG와 ${Ca}^{2+}$로 융합시켰다. 재생배지상에서의 균총의 특징과 균핵의 형성에 의해 7 개의 원형질 융합체를 선발하고 esterase 동위효소의 zymogram 및 AG-1 과 융합체인 F150l 사이에서 일어나는 killing reaction으로 확인하였다.

• 한국응용곤충학회지
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• 제10권1호
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• pp.7-12
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• 1971

1. 인삼묘포에 Captan, Difolatan, Zineb, Maneb와 PCNB를 일주일 간격으로 토양관주 하였다. 처리하기전과 2회 및 4회처리후에 각각 Rhizoctonia solani, Pythium debaryanum, Fusarium 그리고 Trichoderma 균총의 숫적 (수적)변화를 Boosalis의 특별잔사법에 의해서 조사하였다. 우리나라에서 인삼(Panax ginseng)의 모잘록병균으로서 Pythium debaryanum을 처음으로 기술하였다. 2. Rhizoctonia solani, Pythium debaryanum의 수는 토양관주에 관계없이 시일이 경과함에 따라서 점차로 감소하였고 Fusarium 및 Trichoderma는 오히려 증가하였다. Rhizoctonia solani의 수는 PCNB에 의해서 현저하게 감소하였고 다른 약제에 의해서도 대조구 보다 감소하였다. 3, Pythium debaryenum은 Zineb, Maneb, Captan, Difolatan의 순으로 고 수가 증가하는 반면 Fusarium은 일정한 경향을 볼 수 없었다. Tichroderma를 제외한 모든 균의 숫적 변화는 시일의 경과에 대하여 $1\%$ 수준에서 유의성이 있었다. 4. 토양관주에 의한 약해는 Maneb, Zineb, Captan 구에서 나타났고 묘삼 뿌리의 생체 무게는 Difolatan, PCNB, Maneb구에서 대조구 보다 증가하였다.

• 한국미생물·생명공학회지
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• 제33권2호
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• pp.112-116
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• 2005

스웨덴 산림지역의 토양시료로부터 분리한 Bacillus licheniformis KMU-3의 작물병원성 곰팡이에 대한 항진균 활성 및 항진균물질의 생산조건에 대하여 검토했다. B. licheniformis KMU-3은 Rhizoctonia solani KACC 40101에 대하여 높은 항진균활성을 나타냈었다. 항진균물질 생산을 위한 최적배양조건은 탄소원으로 $1.0\%$ sodium acetate, 질소원으로는 $1.0\%$ ammonium sulfate, $24^{\circ}C$, pH 8.0, 180 rpm, 24시간 진탕배양하였을 때 가장 높은 항진균활성를 나타내었다. TLC상에서 Rf값이 0.49인 밴드에 나타난 물질에서 항진균활성이 확인되었으며, 이물질은 Rhizoctonia solani AG-4 KACC 40142, Colletotrichum orbiculare KACC 40808, Colletotrichum gloeosporioides KACC 40804, Cladosporium cucumerinum KACC 40576, Fusarium graminearum KACC 41040, Fusarium oxysporum KACC 40052에 대하여서도 높은 항진균활성을 나타내었다.

• 농약과학회지
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• 제9권1호
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• pp.35-40
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• 2005

Rhizoctonia solani AG-4에 의하여 발생하는 여름 시금치 잘록병은 매우 중요한 병이다. 이 병을 방제하기 위하여 13종(pencycuron, trifloxystrobin, pyraclostrobin, azoxystrobin, kresoxim-methyl, validamycin, fluazinam, Benlate-T, flutolanil, cyazofamid, hexaconazole, tebuconazole, prochloraz)의 살균제의 약효를 in vitro와 in vivo 검정을 통하여 평가하였다. In vitro 균사생장 억제 시험 결과 pencycuron, pyraclostrobin, validamycin, fluazinam, Benlate-T, hexaconazole, tebuconazole, flutolanil이 병원균의 생장을 크게 억제하였다. 그러나 trifloxystrobin, azoxystrobin, kresoxim-methyl, cyazofamid, prochloraz은 억제 정도가 낮게 나타났다. 살균제들을 관구처리한 유묘검정(2,000 mg/L)에서 pencycuron, pyraclostrobin, validamycin, fluazinam, Benlate-T, flutolanil은 97.8%, 84.4%, 93.3%, 95.6%, 91.1%, 86.7%의 생존율을 나타냈고, 2,000 mg/L의 농도로 종자처리하였을 때 pencycuron과 pyraclostrobin은 85.1% 이상의 생존율을 나타내었다.

• 식물병연구
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• 제11권1호
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• pp.77-79
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• 2005

2002년 전북지방에 야생하는 칡의 잎에 잎마름병이 발생하였다. 병징은 잎과 어린 줄기에 발생하고 잎에 처음에는 수침상 병반이 나타나고 잎의 가장자리 부분부터 갈색을 띠면서 안쪽으로 말라 들러가기 시작하였다. 병이 진전되면 잎과 어린 줄기는 갈변하며 낙엽 되었다. 병원균은 PDA에서 기중균사를 형성하고, 처음에는 흰색을 띠다가 연한 갈색으로 변하였다. 균사는 $90^{\circ}$로 분지하고, 대부분 하난의 세포에 다핵을 형성하였다. 또한 PDA에서 부정형 또는 타원형으로 0.5~3.0mm의 균핵을 형성하였다. 본 연구에서 칡의 잎에 마름병을 일으키는 병원균의 균학적 특징 및 형태적 특징을 조사한 결과, Rhizoctonia solani Kuhn에 의한 칡 잎마름병으로 명명하고자 제안한다.

• The Plant Pathology Journal
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• 제17권4호
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• pp.210-215
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• 2001

The phenotype of Rhizoctonia solani KR-13 was randomly segregated to both melanin-producing (M+) and non-producing (M-) types through successive cultures on PDA. M+type with dark melanin showed strong pathogenicity to rice and self-anastomosis. Meanwhile, M- type with white or less-melanized mycelia showed very weak pathogenicity and non-self-anastomosis. Melanin production of R. solani was affected by incubation temperature in both M+ and M- types, but not by light treatment. The application of tricyclazole, an inhibitor of fungal melanin biosynthesis, showed no controlling effect on R. solani causing rice sheath blight. Results of this study showed that melanization of mycelia of R. solani is an important pathogenicity factor in rice.

• The Plant Pathology Journal
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• 제15권1호
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• pp.68-71
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• 1999

To illustrate the action mechanism of pencycuron on Rhizoctonia solani, two experiments were conducted including the comparison of amino acids of $\beta$-tubulin between R-C (sensitive isolate) and Rh-131 (non-sensitive isolate), and the inhibitory effect of pencycuron on tubulin assembly in vitro. Both $\beta$-tubulin genes of R-C and Rh-131 proved to have 1,582 nucleotides encoding a protein of 445 amino acids, showing 98% homology in amino acid sequences between them. It was found that codons at 103, 236, and 267 for lysine (AGG), valine (GTC) and isoleucine (ATT) in R-C were replaced by codons for methionine (ATG), isoleucine (ATT) and methionine (ATG) in Rh-131, respectively. No inhibitory effect of pencycuron on the tubulin assembly was observed. It suggests that pencycuron may have no direct inhibitory effects on the assembly of tubulin at least in vitro.