• 한국응용곤충학회지
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• 제22권3호
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• pp.203-207
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• 1983

인삼 근부병 억제토양 및 유발토양의 생물적, 이화학적 특성을 조사하였다. 병원균 Fusarium solani에 대한 길항균의 밀도가 근부병 유발토양에 비해 억제토양에서 훨씬 높았으며, 반대로 Fusarium spp.의 밀도는 더 낮았다. F solani의 후막포자 형성 및 균사생장도 근부병 억제토양에서 더 적었으며, 억제토양의 물추출액 속에서도 처리 4시간후 대형분생포자의 발아관이 길항미생물에 의해 분해되었다. 두 토양의 이화학적인 성질은 유의성있은 차가 없었으나 억제토양이 유발토양보다 점토함량이 조금 높은 경향이었다.

• Mycobiology
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• 제43권2호
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• pp.170-173
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• 2015

Herein, we report the first occurrence of web blight of rosemary caused by Rhizoctonia solani AG-1-IB in Gangneung, Gangwon Province, Korea, in August 2014. The leaf tissues of infected rosemary plants were blighted and white mycelial growth was seen on the stems. The fungus was isolated from diseased leaf tissue and cultured on potato dextrose agar for identification. The young hyphae had acute angular branching near the distal septum of the multinucleate cells and mature hyphal branches formed at an approximately $90^{\circ}$ angle. This is morphologically identical to R. solani AG-1-IB, as per previous reports. rDNA-ITS sequences of the fungus were homologous to those of R. solani AG-1-IB isolates in the GenBank database with a similarity percentage of 99%, thereby confirming the identity of the causative agent of the disease. Pathogenicity of the fungus in rosemary plants was also confirmed by Koch's postulates.

• 식물병연구
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• 제28권4호
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• pp.245-247
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• 2022

In August 2021, we surveyed diseases of wild vegetables grown in Taebaek, Gangwon Province, Korea. During the disease survey, we observed severe damping-off symptoms in young edible aster (Aster scaber) plants in a vinyl greenhouse investigated. The incidence of the disease in the plants ranged from 5% to 20%. Diseased plants of edible aster were collected from the vinyl greenhouse, and fungi were isolated from petiole lesions of the diseased plants. Rhizoctonia sp. was consistently isolated from the petiole lesions. We examined morphological characteristics and anastomosis groups of nine Rhizoctonia sp. isolates obtained from the petiole lesions. The examination results revealed that all the isolates corresponded to Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for their pathogenicity on edible aster plants by artificial inoculation. Inoculation tests showed that the tested isolates caused damping-off symptoms on the inoculated plants. The induced symptoms were similar to those observed in the vinyl greenhouse investigated. Damping-off of edible aster caused by R. solani AG-4 is first reported in this study.

• 아시안잔디학회지
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• 제13권3호
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• pp.131-138
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• 1999

A synergistic effect of biocontrol agent and chemicals on control of the large patch on turfgrass caused by Rhizoctonia solani AG2-2 was evaluated. Chemicals; mepronil, toclofos-methyl and iprodione inhibited 90∼100% mycelial growth of R. solani AG1 and AG2-2 in vitro. While on the other, the chemicals inhibited only 0∼5%, 18∼46% and 30∼67% of mycelial growth of the antagonists, respectively. In field application, toclofos-methyl was the best to suppress the disease in single application, however, the combination of mepronil and T. viride 41D showed highest disease control effect among combinations of antagonists and chemicals. Effect of the combination of mepronil and T. viride 41D was similar to that of toclofos-methyl and T. viride 41D stage of disease development, but became higher in six week late. Results indicated that the combined application of selected antagonistic agent and chemical increased control efficasy of turgrass large patch.

• 한국식물병리학회지
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• 제11권1호
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• pp.47-52
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• 1995

One hundred and thirty bacterial isolates with high chitinolytic activity on chitin agar media were isolated and identified. Most of the isolates were Aeromonas hydrophila (110 isolates), and the others were Serratia marcescens (11 isolates), Aeromonas caviae (3 isolates), Chromobacterium violaceum strain C-61 (2 isolates), Chromobacterium violaceum strain C-72 (1 isolate) and unknown species (3 isolates). Among them, C. violaceum strain C-61 had highest chitinolytic activity and fungal growth inhibition on PDA. This bacterium also inhibited the growth of Rhizoctonia solani, Sclerotinia scelrotiorum, Phytophthora capsici and Pythium ultimum, but it didn't inhibit the growth of Fusarium oxysprum and Fusarium solani. C. violaceum strain C-61 suppressed damping-off of eggplant caused by R. solani. Populations of the chitinolytic bacteria such as Aeromonas hydrophila, Serratia marcescens, Aeromonas caviae, Chromobacterium violaceum strain C-61 and Chromobacterium violaceum strain C-72 introduced into R. solani-infested soil were continuously decreased until 20 days after treatment, but their populations except A. caviae were not changed significantly and maintained over 5$\times$104 CFU per g of soil thereafter.

• 아시안잔디학회지
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• 제8권1호
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• pp.47-52
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• 1994

Attempts were made to investigate the antagonistic activity of soil borne microorganisms Pseudomonas spp. and Trichoderma spp. against to the pathogens of turf diseases Rhizoctionia solani spp. and Pythiom spp. in vitro by a dual culture bioassay. Inhibition zone between the edge of the my-celium and the margin of each antagonistic bacteria, Pocudontonas, on potato dextrose agar was measured 3 days after incubation at 28˚C. Psudomonas spp. showed relatively high inhibition of mycelium growth of R. solani AG-i and Pythium spp. which cause brown patch and pythium blight, respectively. Antagonistic fungi Trichodenma spp. also showed effective inhibition against mycelium growth of both pathogens, more proper methods of measuring the inhibition effects were required because of fast growth of Trichodenna hypae. Brown patch and pythium blight both, re-quire most higher rate of fungicide use to control in golf curses in Korea. Application of antagon-istic microorganisms are useful as biological resources an approach to sole environmental contamination.

• 한국균학회지
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• 제49권3호
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• pp.413-416
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• 2021

In July 2019, damping-off symptoms of young Fischer's ragwort (Ligularia fischeri) plants were observed in four vinyl greenhouses of a farmer located in Taebaek, Gangwon Province, Korea. This disease occurred in 20-30% of plants in the vinyl greenhouses investigated. Nine isolates of Rhizoctonia sp. were obtained from the diseased plants. All the isolates were identified as Rhizoctonia solani AG-2-2 (IIIB), based on morphological, cultural characteristics, and anastomosis test. Three isolates were used for artificial inoculation test on Fischer's ragwort. Pathogenicity of these isolates was confirmed on the plants with the inoculation tests. Damping-off symptoms observed on the inoculated plants were similar to those observed in the diseased plants in the vinyl greenhouses. This is the first report of R. solani AG-2-2 (IIIB) being the causative agent in damping-off in Fischer's ragwort.

• 식물병연구
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• 제17권3호
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• pp.405-409
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• 2011

연 재배연못에서 발견된 큰물개구리밥에 R. solani AHL1에 의해 국지적으로 말라 고사하는 것을 관찰하였다. 병원균을 분리하여 형태적 특징을 조사한 결과 균사는 두께가 $5-6{\mu}m$이고 둔각분지를 하고 있었으며 핵형은 다핵형이었다. 배양적 특성으로 균사생육은 $25^{\circ}C$에서 가장 왕성하였으며 $30^{\circ}C$에서 가장 많은 균핵이 형성되었다. 온도에 따른 병원성과 발병정도를 조사한 결과 $20^{\circ}C$, $25^{\circ}C$와 $30^{\circ}C$에서 모두 병원성이 나타났으며 발병정도는 $30^{\circ}C$에서 가장 높게 나타났다. 병원균을 유전자 수준에서 동정하기 위해 ITS 영역을 Neighbor-Joining 방법을 이용하여 계통분류분석을 수행한 결과 R. solani로 동정되었다. 본 연구에서 분리된 R. solani AHL1은 벼잎집무늬마름병을 유발하는 병원균과 유사하여 벼에 대한 병 발생 여부는 추가적으로 연구가 필요하다. 현재 농업은 화학비료의 사용을 억제하는 추세로 녹비를 이용한 유기농업으로, 주요 녹비인 Azolla 안정적인 사용을 위하여 Azolla에 발생하는 병에 대한 연구가 더 이루어져야 된다고 사료된다.

• 한국미생물·생명공학회지
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• 제31권4호
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• pp.421-428
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• 2003

길항미생물을 이용한 항곰팡이성 퇴비의 개발을 목적으로 공시 식물로써 Spinacia oleracea L과 식물 병원균 Rhizoctonia solani Kuhn O-28을 모델로 사용하여 수행 되었다. 다양한 음식쓰레기를 일년동안 숙성시킨 퇴비로부터 80 균주를 분리하였고, 그 중 No.15-2 균주가 R. solani Kuhn O-28에 대해 가장 높은 항곰팡이 활성을 보였다. 16S rDNA sequencing과 primer pair PCR에 의해 표현형과 분류학적으로 거의 독성이 없는 것으로 밝혀진 Burkholderia cepacia genomoval V로 분류되었다. 이 B. cepacia No. 15-2가 퇴비화 중에 우점하였으며 그 균수는 15일 동안 거의 $10^{13}$ cfu/g을 유지하였다. S. oleracea L을 배양 했을 경우 R. solani Kuhn O-28에 의한 발병율은 B. cepacia No.15-2를 첨가함으로써 40% 감소하였다. 결론적으로 B. cepacia No.15-2는 다양한 식물의 곰팡이 유래의 병을 방제하는 데 이용 가능할 것으로 사료된다.

• The Plant Pathology Journal
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• 제29권4호
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• pp.440-445
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• 2013

Balloon flower (Platycodon grandiflorum) is a kind of mountain herbs whose roots have restorative properties and the cultivating acreage of balloon flower has been steadily increasing in Korea. More frequent rain and high amount of rainfalls as a result of climate changes predisposed balloon flower to the outbreaks of root rot at high-density cultivation area in recent years. Root crowns were usually discolored into brown to blackish brown at first and the infected plants showed slight wilting symptom at early infection stage. Severely infected roots were entirely rotted and whole plants eventually died at late infection stage. The overall disease severities of root rot of balloon flower were quite variable according to the surveyed fields in Jeonnam, Gyeongnam and Jeju Provinces, which ranged from 0.1% to 40%. The root rot occurred more severely at the paddy or clay soils than the sandy soils and their severities were much higher at lowland than upland in the same localty. The disease increased with aging of the balloon flower. The causal fungi were identified as Fusarium solani and F. oxysporum on the basis of their mycological characteristics. The optimum temperature ranges of their mycelial growths was found to be $24^{\circ}C$. The pathogenic characters of F. solani and F. oxysporum treated by artificial wounding inoculation on healthy roots of balloon flower revealed that F. solani was more virulent than F. oxysporum. This study identified the causal agents of root rot of balloon flower as Fusarium solani and F. oxysporum, probably for the first time.