• The Plant Pathology Journal
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• 제20권4호
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• pp.271-276
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• 2004

To examine the control effect of damping-off on radish caused by Pythium spp., researchers used the isolates of a fungivorous nematode, Aphelenchus avenae, and antagonistic fungi, Trichoderma spp. These were used as biocontrol agents, either alone, or in combination. Growth rates of the A. avenae isolates and fungal damages by the nematodes varied depending on Trichoderma spp., which contained lower T. koningii and T. virens cultures than other Trichoderma cultures. Phythium spp. were damaged by all five Aphelenchus isolates, but the multiplication rate of nematode isolate Aa-3 was very poor. Antibiotic activity of T. virens and T. harzianum to Pythium spp. was stronger than that of T. koningii. Control efficacy against damping-off of radish was most enhanced under the treatment using the nematode-T. harzianum combination. On the contrary, the combinations of the nematodes and T. virens or T. koningii mostly did not increase or decreased their control effect vis-$\`{a}$-vis that of the nematodes or antagonistic fungi being used alone. The results suggest that the fungivorous nematodes may play a leading role in the disease control, and that the activity of the fungivorous nematodes may be activated by T. harzianum, but inhibited by T. koningii and T.virens.

• 생명과학회지
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• 제12권4호
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• pp.416-422
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• 2002

B. ehimensis YJ-37은 생육촉진미생물이면서 모잘록병의 생물학적 방제균으로서 관찰되었다 길항균 B. ehimensis YJ-37의 무와 수박의 근권정착밀도는 인공용토에 존재하는 길항균의 평균밀도 $10^4$(cfu/g) 보다 주근과 측근에서 약 1.2~2배 이상의 증가하였다. 길항균 배양액으로 만든 토양미생물제제에 의한 무의 생육촉진은 토양미생물제제 무처리구에 비해 처리구에서 잎면적은 85% 자엽의 길이는 33% 뿌리의 길이는 23% 건조중량은 89% 촉진되었고, 수박의 경우도 무처리구에 비해 처리구에서 잎면적은 63% 자엽의 길이는 27% 뿌리의 길이는 25% 건조중량은 69% 촉진되었다. 토양미생물제제는 채소류 모잘록병균 R. solani AG-4와 P. ultimum 등의 생육을 억제하여 모잘록병을 유발시키지 못하게 하였으며, 생육촉진현상도 동시에 가져왔다.

• The Plant Pathology Journal
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• 제27권1호
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• pp.68-77
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• 2011

Fifty five species of medicinal plant materials were tested for their antifungal activity in vitro against Rhizoctonia solani AG 2-1 and Trichoderma harzianum to select plant species that can be used to improve the biocontrol efficacy of T. harzianum. Six species were effective against R. solani AG 2-1 but were also antagonistic to T. harzianum, except for Cinnamomum loureirii stem bark (CSB). CSB inhibited mycelial growth of R. solani AG 2-1 by 73.7% but showed an inhibitory effect on mycelial growth of T. harzianum by only 2.2%. Scanning electron microscophs showed that the CSB treatment resulted in deformed R. solani AG 2-1 hyphal cells, and transmission electron microscophs revealed degenerated cell structures such as degenerated cytoplasm and disentangled cell wall and the accumulation of electron-dense inclusions (asterisks) in the CSB treatment. The biocontrol efficacy of radish damping-off increased greatly following the combined treatments of T. harzianum and CSB and the combined treatment increased efficacy from 6.4-23.1% to 37.1-87.3% compared with either treatment alone. CSB did not affect T. harzianum population growth, as it was almost the same in rice-bran peat medium (culture) amended with 0.1% and 1.0% CSB powder as in non-amended medium. The formulation of T. harzianum in rice-bran peat medium amended with CSB powder reduced the severity of radish damping-off by 80.6%, suggesting that T. harzianum and CSB can be formulated as a biocontrol product for the control of R. solani AG 2-1.

• Journal of Microbiology and Biotechnology
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• 제18권9호
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• pp.1537-1543
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• 2008

We tested Trichoderma harzianum as a biocontrol agent for Rhizoctonia solani AG2-1, using six natural antifungal materials to improve its efficacy. Among the six materials tested, peony (Paeonia suffruticosa) root bark (PRB) showed the strongest antifungal activity against R. solani AG2-1, and was not antagonistic to T. harzianum. Scanning electron microscopy showed that treatment with PRB extract resulted in shortened and deformed R. so/ani AG2-1 hyphal cells. The control of radish damping-off caused by R. so/ani AG2-1 was greatly increased by combined treatments of T. harzianum and PRB, as compared with either of the two treatments alone, with the control effect increased from 42.3-51.5% to 71.4-87.6%. The antifungal compound in PRB, which was isolated in chloroform and identified as paeonol by mass spectrometry, $^1H$ NMR, and $^{13}C$ NMR analyses, inhibited the growth of R. so/ani AG2-1 but not that of T. harzianum. Thus, PRB powder or extract may be used as a safe additive to T. harzianum to improve the control of the soil borne diseases caused by R. so/ani AG2-1.

• 한국식물병리학회지
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• 제2권3호
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• pp.193-198
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• 1986

우리나라의 미기록 병인 Rhizoctonia solani Kuhn에 의한 배추 밑동썩음병(Bottom rot)에 대한 남부지방파로재배 시의 발병소장과 방제방법을 검토하였다. 본 병의 발병은 정식 20여일 경과후, 배추의 생육중기부터 발병되기 시작하여 결구기에 증가하는 경향이고, 수확기의 발병주율은 평균 $52\%$ 정도였다. 그 피해는 추파로지재배보다 비닐하우스를 이용한 반촉성재배에서 심하였고, 초기에 심엽까지 감염된 이병주는 위축되어 생육이 극히 불량하여 결구가 되지 않았다. 병주에서 분리한 R. solani의 PDA배지상에서 균사 생육적온은 $20\~25^{\circ}C$였고, 균사융합군은 제II군 제1형으로 분류되었다. 배추, 무, 참깨 및 유채의 유묘에 접종했을 때 입고율이 매우 높았고 상치, 토마토, 오이에서는 입고율은 낮았으나 발아가 $2\~3$일 지연되었다. 방제약제는 발병초기부터 pencycron Wp.를 10일간 3회 처리한 것이 방제가가 $80\%$로 우수하였다.