• 한국균학회지
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• 제49권2호
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• pp.249-251
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• 2021

Damping-off symptoms were frequently observed in young deltoid synurus (Synurus deltoides) plants grown in a farmer's vinyl greenhouse located in Hwacheon, Gangwon Province, Korea, during a disease survey in July 2019. The incidence of diseased plants in the vinyl greenhouse investigated was 5-30%. Five isolates of Rhizoctonia sp. were obtained from the diseased plants and identified as Rhizoctonia solani AG-1 (IB), based on morphological and cultural characteristics and anastomosis test results. Three isolates of R. solani AG-1 (IB) were tested for pathogenicity on deltoid synurus using artificial inoculation. All the tested isolates induced damping-off symptoms in the inoculated plants. The symptoms were similar to those observed in plants from the farmer's vinyl greenhouse. To our best knowledge, this is the first report of R. solani AG-1 (IB) causing damping-off in deltoid synurus.

• 한국균학회지
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• 제49권1호
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• pp.133-137
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• 2021

Foot rot symptoms were occasionally observed on young bok choy (Brassica rapa subsp. chinensis) and kale (B. oleracea var. viridis) plants grown in vinyl greenhouses located in Icheon and Yangpyeong, Gyeonggi Province, Korea. These observations were made during disease surveys in April 2020. The incidence of diseased plants in the vinyl greenhouses investigated was 0.5-1.0% in bok choy and 0.5-5.0% in kale. Five isolates of Rhizoctonia sp. were obtained from diseased roots of bok choy and three isolates of Rhizoctonia sp. were taken from diseased stems of kale. All the Rhizoctonia sp. isolates were identified as Rhizoctonia solani AG-2-1 based on the morphological characteristics and anastomosis test. Three isolates each of R. solani AG-2-1 from bok choy and kale were tested for pathogenicity in their host plants by artificial inoculation. The tested isolates induced foot rot symptoms on the inoculated bok choy and kale plants. The symptoms on the bok choy and kale, induced by the artificial inoculation, were similar to those observed on plants from the vinyl greenhouses that were investigated. This is the first report of R. solani AG-2-1 causing foot rot in bok choy and kale in Korea.

• 한국균학회지
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• 제48권3호
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• pp.325-328
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• 2020

Damping-off symptoms were frequently observed on young plants of edible amaranth (Amaranthus mangostanus) grown in vinyl greenhouses by farmers located in Goyang and Yangpyeong in Korea during disease surveys carried out in 2019 and 2020. The incidence of the disease was 1-20%. A total of eight isolates of Rhizoctonia sp. were obtained from the stems of the diseased plants. All the isolates were identified as Rhizoctonia solani AG-4, based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on edible amaranth by artificial inoculation. All the tested isolates of R. solani AG-4 induced damping-off symptoms on the inoculated plants; these symptoms were similar to those observed on the vinyl greenhouse plants surveyed. This is the first report of R. solani AG-4 causing damping-off in edible amaranth.

• 식물병연구
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• 제27권1호
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• pp.45-47
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• 2021

Damping-off symptoms were frequently observed on young plants of coastal hogfennel (Peucedanum japonicum) grown in a farmer's vinyl greenhouse located in Goseong, Gangwon Province, Korea during a disease survey in June 2019. Incidence of the diseased plants was 50-70% in the vinyl greenhouse investigated during the disease survey. Eight isolates of Rhizoctonia sp. were obtained from the diseased plants. All the isolates were identified as Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on coastal hogfennel by artificial inoculation. All the tested isolates induced damping-off symptoms on the inoculated plants. The symptoms were similar to those observed in the farmer's vinyl greenhouse investigated. This is the first report of R. solani AG-4 causing damping-off in coastal hogfennel.

• Weed & Turfgrass Science
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• 제2권1호
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• pp.88-94
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• 2013

Rhizoctonia solani AG-1 IB에 의한 갈색잎마름병(brown patch)이 경북 청도에 있는 골프장에서 2010년 5월 하순과 10월 초순에 Kentucky bluegrass에서 발생하였다. 봄철에 발병증상은 잎끝과 잎이 마르는 증상이 갈색의 patch 형태로 나타났다. 하지만, 가을철에는 검은 갈색과 회갈색의 patch 모양으로 나타났다. 갈색잎마름병의 곰팡이는 병든 잎에서 분리를 하였으며, 동정을 위하여 PDA에서 배양하였다. 어린 균사는 분지각이 좁은 형태와 격막이 있었고, 분지각이 $90^{\circ}C$인 성숙한 균사와 monilioid 세포가 발달된 것도 볼 수 있었다. B-7 균주의 리보소옴 RNA의 염기서열을 분석하여 유전자은행에 Rhizoctonia solani AG-1 IB 균주와 비교한 결과, 99% 상동성을 나타낸다는 것을 확인하였다. 병원성도 creeping bentgrass와 Kentucky bluegrass에서 Koch's 원칙에 따라 확인하였다. Kentucky bluegrass에 갈색잎마름병은 Rhizoctonia solani AG-1 IB에 의한 것임을 처음보고 한다.

• 한국균학회지
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• 제50권1호
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• pp.61-64
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• 2022

In July and September 2020, a severe outbreak of stem rot was observed on bonnet bellflower (Codonopsis lanceolata) plants in a farm located in Chuncheon, Gangwon Province, Korea. The symptoms initially appeared on the stem at or above the soil line. Later, the infected stem completely rotted and blighted. The incidence of diseased plants in the field was 2-30%. Ten isolates of Rhizoctonia sp. were obtained from the stem lesions of diseased plants. All isolates were identified as Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for pathogenicity on bonnet bellflower plants through artificial inoculation. All tested isolates induced stem rot symptoms on the inoculated plants. The symptoms were similar to those observed in plants from the farm. This is the first report of R. solani AG-4 causing stem rot in bonnet bellflower.

• 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.

• 아시안잔디학회지
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• 제9권3호
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• pp.235-252
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• 1995

Turfgrass Rhizoctonia blight is a severe disease in golf courses in Korea. Attempts were made in 1989 to 1994 to identify the Rhizoctonia species associated with turfgrass blights and also to examine their epidemiology. A total of 120 Rhizoctonia isolates collected were identified as R. solani AG1, R. solani AG2-2, R. cerealis(AG-D) and R. oryzas from brown patch, large patch, yellow patch and white patch, re-spectively. R. solani AG1 was mostly associated with brown patch of cool-season grasses. and most frequently isolated in June through July and also in September. R. solani AG2-2 was isolated exclusively from zoysiagrasses from April to November, most frequently in June through July and October through November. R. cerealis was isolated frequently from both creeping hentgrass in March through April and in November, and zoysiagrass in April and July. Thermophilic R. oryzae was isolated only from creeping bentgrass in August, although with very low frequency. R. solani AG2-2 was strongly pathogenic specifically to Korean lawngrasses(Zoysia japonica, Z.matrella, Z. tenuifolia), but non-pathogenic to creeping bentgrass(Agrostis palustris), bermudagrass (Cynodon dactylon), Kentucky bluegrass(Poa pratensis), perennial ryegrass(Lolium prenne), and creeping red fescue(Festuca rubra subsp. ruhra L.). R. cerealis was strongly pathogenic to zoysiagrass and bentgrass only, but was isolate-specific i.e., from non-pathogenic to pathogenic, for other turfgrasses. The mycelial growth was optimum at relatively high temperature ranges of 25~30$^{\circ}C$ for R.solani AG1, AG2-2 and R. oryzae, while the mycelial growth of R. cerealis was initiated at $^{\circ}C$ and almost ceased at or above $^{\circ}C$.

• 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.

• 한국식물병리학회지
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• 제3권3호
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• pp.217-222
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• 1987

남부지방의 고추, 오이, 대추, 딸기, 수도 등에 발생한 모잘록병 이병주에서 분리한 9가지 Rhizoctonia solani 균주의 고추, 오이, 무, 대추에 대한 병원성을 조사한 결과를 요약하면 다음과 같다. AGI 균주는 공시한 모든 기주에 대해 강한 병원성이 있었고, AG2군 1형 균주는 무와 배추에 대해서는 강한 병원성을, 고추에 대해서는 묘령이 증가함에 다라 발병이 적어 중정도의 병원성이 있었으나, 오이에 대해서는 병원성이 매우 약한 경향이었다. AG2군 2형 균주는 고추를 제외한 나머지 작물에는 병원성이 없거나 약하였고, AG5 균주는 공시한 모든 기주에 대해 중정도의 병원성이 있었다. 각 균주의 병원성 정도는 균계융합군(AG)간에는 차이가 있었으나, 같은 균사융합군(AG)내에서는 큰 차이가 없었다. 즉, AG1은 공시한 모든 기주에 강한 병원성을 보였으며, AG2군 1형 균주는 오이에 대해서만 약한 정도의 병원성을, 다른 기주에 대해서는 강한 병원성을 나타내었다. 각 기주의 묘령별 발병율은 살균토나 비살균토에서 묘령이 많을수록 감소하는 경향을 보였으나, 오이 뿌리와 수도줄기에서 분리한 병원성이 강한 균주에 대해서 각 기주는 묘령에 따른 발병율의 차이가 없었다. 살균토와 비살균토에서 병원성을 비교하면 병원균이 분리된 기주 및 근록의 작물에 대해서는 비살균토보다 살균토에서 더 강한 병원성을 보였으나, 병원균이 분리된 작물과 원록의 작물에 대해서는 살균토보다 비살균토에서 더 강한 병원성을 보였는데, 전반적으로는 다른 토양전염성병과는 달리 살균토보다 비살균토에서 병원성이 더 강하였다.