• Mycobiology
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• 제38권3호
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• pp.210-214
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• 2010

Selection of fungal strains with high virulence against the developmental stages of Bemisia tabaci was performed using internal transcribed spacer regions. The growth rate of hyphae was measured and bioassay of each developmental stage of B. tabaci was conducted for seven days. All of the fungal strains tested were identified as Lecanicillium spp., with strain 4078 showing the fastest mycelium growth rate (colony diameter, 16.3 $\pm$ 0.9 mm) among the strains. Compared to strain 4075, which showed the slowest growth rate, the growth rate of strain 4078 was increased almost 2-fold after seven days. Strains 4078 and Btab01 were most virulent against the egg and larva stages, respectively. The virulence of fungal strains against the adult stage was high, except for strains 41185 and 3387. Based on the growth rate of mycelium and level of virulence, strains 4078 and Btab01 were selected as the best fungal strains for application to B. tabaci, regardless of developmental stage.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권2호
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• pp.143-146
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• 2007

Concerns of entomopathogenic fungi as alternative pest control agents are increasing even though chemical pesticides have been used as the main control agents for pests and diseases in crop production. This study was conducted to test the influence of fungicides and insecticides on an isolate of Lecanicillium attenuatum that was reported to have the pathogenicity against cotton aphid, because fungicides and/or insecticides can apply with mycopesticides simultaneous, before and/or after. Fungicides fenbuconazole+thiram and propineb inhibited the spore germination and mycelial growth of L. attenuatum CS625; dimethomorph and procymidone did not affect spore germination or mycelial growth. The insecticide abamectin, deltamethrin, imidachropride, and spinosad had no detrimental effects on spore germination or mycelial growth. Therefore, these results demonstrated that careful selection of pesticides and fungicides can be applied to the integrated pest and disease control with microbial pesticide.

• Mycobiology
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• 제36권3호
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• pp.183-189
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• 2008

The production of aerial conidia of Lecanicillium lecanii 41185, a highly virulent fungus, by solid-state fermentation was studied for use as a biocontrol agent against aphids. Among several agro-industrial solid media, steamed polished rice was found to produce the highest amount of aerial conidia. The optimal conditions for aerial conidia production were determined to be a 28.5% moisture content in the rice, 25$^{\circ}C$ culture temperature, rice pH of 6.0, 75% ambient relative humidity, 4-dold seeding culture, 0.6% $KNO_3$, and 12 d of culture time. The conidia yield increased from $5.7\times10^9$ conidia/g polished rice to 18.2 $18.2\times10^9$ conidia/g polished rice following application of these optimized conditions.

• 한국균학회지
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• 제34권2호
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• pp.112-118
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• 2006

본 연구는 채소류 생산 농가에서 막대한 피해를 주고 있는 해충인 진딧물에 대한 방제효과가 우수한 환경친화적 살충성 미생물 개발을 위한 기초연구로서 살충효과를 갖는 Lecanicilium(Verticillium)속의 우수 균주를 선발하고, 포자생산을 위한 배지를 선정하며, 분자 동정법을 확립하여 새로운 균주 탐색을 위한 기틀을 마련하고자 실시하였다. 새로 동정된 Lecanicillium속 5균주를 이용하여 복숭아혹진딧물(Myzus persicae)에 살충력 시험과 균주들의 여러 특성들을 조사한 결과, 4078 균주는 실온과 $30^{\circ}C$에서 우수한 살충력을 나타냈으며, $30^{\circ}C$에서 2일 만에 100%의 살충성을 보였다. 한편, 낮은 상대 습도에서 가장 우수한 균주는 RH 85%에서 5일 동안 90%의 살충성을 보인 6543 균주이었다. 이들 4078과 6543균주들의 ITS의 DNA 염기서열(accession no.: 순서대로 EF026004와 EF026005)에 의해 Lecanicillium 종으로 확인되었다. 한편, 미생물 농약 생산에 중요한 포자 생산에 있어서 6543 균주가 4078 균주보다 월등히 우수하였는데, 6543 균주의 살충력이 4078 균주보다는 다소 낮지만, 살충력이 여전히 우수하며 포자생산량이 많고, 회수에도 용이하기 때문에, 미생물농약으로서는 6543 균주가 가장 적합하다고 판단된다.

• Journal of Microbiology and Biotechnology
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• 제18권12호
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• pp.1915-1918
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• 2008

An entomopathogenic fungus was isolated from an infected aphid. The isolate conformed most closely to Lecanicillium attenuatum CBS 402.78 (AJ292434) based on the internal transcribed spacer (ITS) region of its 18S rDNA, and thus was designated L. attenuatum CNU-23. Laboratory and field evaluations of CNU-23 blastospores were carried out for the control of green peach aphids. The laboratory evaluations of CNU-23 revealed an aphid mortality of about 80% with an estimated $LT_{50}$ of 3.72 days after the application of CNU-23 at $1{\times}10^6$ blastospores/ml. Meanwhile, the field evaluations of CNU-23 performed on greenhouse pepper plants during the rainy season showed an aphid mortality ranging from 72% to 97%. Significant sporulation was observed in the aphids treated with CNU-23. Therefore, the results suggest that L. attenuatum CNU-23 can be used as a biocontrol agent for green peach aphids on greenhouse pepper plants.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 춘계학술대회 및 임시총회
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• pp.55-55
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• 2015

Rust is one of the most destructive diseases on economically important plants such as agricultural and horticultural crops, as well as forest trees [1]. Chemical treatment is the most effective means to control rust, but use of the chemical fungicides involves inevitable risks to human health and environment [2]. Unfortunately, biocontrol is currently impracticable for rust disease management [3]. It is necessary to exploit biocontrol agents to help prevent rust diseases. As a fundamental research for future development of biocontrol agents for rusts, biodiversity of hyperparasites occurring on rust fungi was investigated. During 2006-2010, 197 fungal isolates of the rust hyperparasites were collected and isolated from various combinations of mycohosts and plant hosts in many regions of Korea. Based on morphological and molecular data, they were identified as 8 genera and 12 species. Besides, phylogenetic relationships between the hyperparasites and related taxa were inferred. A total of 114 isolates of Pseudovirgaria were obtained from rust pustules of Phragmidium spp. and Pucciniastrum agrimoniae infecting rosaceous plants. Phylogenetic analysis using multigene sequences revealed a high level of genetic variability among many isolates of Pseudovirgaria and close correlation between the isolates and mycohosts. Only two species of Pseudovirgaria, P. hyperparasitica and P. grisea are often difficult to distinguish by their morphological similarity, but on the molecular basis they were clearly differentiated from each other. There had been no previous record of P. grisea outside Europe, but the present study has proved its presence in Korea. Among six distinct groups (five of P. hyperparasitica and one of P. grisea) within the Pseudovirgaria isolates, each lineage of P. hyperparasitica was closely associated with specific mycohosts and thus might have cospeciated with their mycohosts, which probably led to coevolution. Although P. grisea possesses a host preference for Phragmidium species occurring on Rubus, it was not specific for a mycohost. P. grisea seems to evolve in the direction of having a broad mycohost range. Seventeen isolates of Verticillium-like fungi were isolated from rust sori. Based on morphological data and DNA sequence analysis, the isolates were identified as three Lecanicillium species, viz. L. attenuatum, Lecanicillium sp. 1, Lecanicillium sp. 2, and V. epiphytum. The unidenified two species of Lecanicillium appear to be previously unknown taxa. Sixty-six isolates of miscellaneous hyphomycetes belonging to 6 species of 5 genera were obtained from pustules of rust fungi. On the basis of morphological and molecular analyses, the miscellaneous hyphomycetes growing on rusts were identified as Acrodontium crateriforme, Cladophialophora pucciniophila, Cladosporium cladosporioides, Phacellium vossianum, Ramularia coleosporii, and R. uredinicola.

• 한국잠사곤충학회지
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• 제51권2호
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• pp.137-141
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• 2013

ITS 1, 2, 5.8S ribosomal RNA gene 염기서열 분석과 주사전자현미경 구조 분석을 통해 3종의 페루산 곤충병원성진균들의 동정을 수행하고자 하였다. 이를 위해 두개의 ITS 부위와 5.8S rRNA gene 부위를 포함하는 PCR product를 증폭하여 염기서열 분석을 수행하였으며 분석된 염기서열을 이용하여 NCBI의 BLAST를 이용하여 가장 높은 상동성을 보이는 종들의 ITS1-5.8S-ITS2 염기서열 정보와 비교분석을 위한 근연종들의 염기서열 정보를 다운로드하여 neighbor joining 분석을 수행하였다. 이를 통해 5.8S rRNA 유전자 염기서열은 속 수준에서도 거의 차이를 보여주지 않을 정도로 매우 안정적으로 보존되어 있음을 확인할 수 있었으며 종간 구분이 모호한 결과를 보여주었다. 그와 반대로 ITS 부위의 염기서열은 종에 매우 특이적임을 확인할 수 있었으며, 비교분석에 사용된 Beauveria bassiana strain 간의 차이는 확인할 수 없었다. ITS 염기서열 분석결과를 뒷받침하고자 곤충병원성 진균류의 동정을 위한 분류 key로 사용되는 미세구조 관찰을 위해 주사전자현미경 관찰과 광학현미경 관찰을 통해 B. bassiana 및 Lecanicillium attenuatum의 전형적 구조를 관찰할 수 있었다.

• 한국균학회지
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• 제43권1호
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• pp.58-63
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• 2015

진균에 의한 오염은 재배사에서 톱밥 배지를 이용한 표고 재배에 중대한 영향을 미치기 때문에 표고 재배사 실내 공기에 존재하는 진균에 대한 모니터링을 수행하던 중 여러 진균을 분리하였다. 분리된 진균 중에는 국내 미기록인 Aspergillus pulverulentus와 Cosmospora butyri 등 2종을 비롯하여 기록은 있으나 균학적 확증이 부족한 Lecanicillium psalliotae와 L. antillanum 등 2종이 존재하였다. 본 논문에서는 이들 균류에 대한 형태적 특성과 더불어 internal transcribed spacer (ITS) rDNA region 또는 ${\beta}$-tubulin 유전자 염기서열에 기반한 계통학적 분석 결과를 기술하였다.

• 한국응용곤충학회지
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• 제49권4호
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• pp.417-422
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• 2010

국내에 문제가 되는 담배가루이(Bemisia tabaci)의 살충성 Lecanicillium lecanii Btab01 균주의 생육 특성과 살충력을 검정하였다. PDA, TSA, SDA+Y배지에서 L. lecanii Btab01은 $20{\sim}25^{\circ}C$에서 균사성장이 가장 빨랐으며 $28^{\circ}C$이상에서 성장이 억제되었다. L. lecanii Btab01는 고체배양과 액체배양 시 담배가루이 약충에 대해 살충률에 큰 차이를 보이지는 않았다(93.9%, 98.3%). 농도별로는 $10^5$, $10^6$, $10^7$, $10^8$ cfu/ml에서 각각 5.8%, 33.8%, 77.3%, 98.5%의 살충률을 보였고 각각 16.1일, 7.3일, 5.1일, 3.5일의 $LT_{50}$값을 나타내었다. L. lecanii Btab01을 약충에 처리 후 포화습도 조건을 0 시간 24 시간, 168 시간 유지하였을 때, 0%, 20.3%, 100%의 살충률을 보였다. 균주에 0.5% 식용유를 첨가하였을 때 포자의 발아가 2 배 가량 증가하였으며 균주에 0.1% 식용유를 첨가하여 약충에 처리했을 때(98.6%)가 첨가하지 않았을 때(79.9%)보다 살충력이 향상됨을 알 수 있었다.

• 한국균학회지
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• 제50권1호
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• pp.1-29
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• 2022

Hypocreales is one of the largest orders within the class Sordariomycetes in Ascomycota. Several species of this order are cosmopolitan and have a broad range of habitats. Here, we isolated several fungal strains from environmental samples, including freshwater sediment and plant litter. The strains were identified via molecular and phylogenetic analyses of rDNA and other DNA markers, such as TUB, RPB2, and EF1. The morphological characteristics of the fungi were investigated using microscopy, and culture characteristics were assessed from their growth on several media. We identified 17 species previously unrecorded in Korea: Dactylonectria hordeicola, Flavocillium bifurcatum, Fusarium luffae, Ilyonectria ilicicola, Ilyonectria qitaiheensis, Ilyonectria robusta, Lecanicillium aphanocladii, Nectria ulmicola, Neonectria lugdunensis, Ovicillium oosporum, Pseudonectria foliicola, Sarocladium spinificis, Scolecofusarium ciliatum, Trichoderma appalachiense, Trichoderma subviride, Trichoderma taiwanense, and Trichoderma tsugarense.