• Mycobiology
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• 제42권4호
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• pp.385-390
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• 2014

The beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae) is difficult to control using chemical insecticides because of the development of insecticide resistance. Several pest control agents are used to control the beet armyworm. Entomopathogenic fungi are one of the candidates for eco-friendly pest control instead of chemical control agents. In this study, among various entomopathogenic fungal strains isolated from soil two isolates were selected as high virulence pathogens against larva of beet armyworm. Control efficacy of fungal conidia was influenced by conidia concentration, temperature, and relative humidity (RH). The isolates Metarhizium anisopliae FT83 showed 100% cumulative mortality against second instar larvae of S. exigua 3 days after treatment at $1{\times}10^7$ conidia/mL and Paecilomyces fumosoroseus FG340 caused 100% mortality 6 days after treatment at $1{\times}10^4$ conidia/mL. Both M. anisopliae FT83 and P. fumosoroseus FG340 effectively controlled the moth at $20{\sim}30^{\circ}C$. M. anisopliae FT83 was significantly affected mortality by RH: mortality was 86.7% at 85% RH and 13.4% at 45% RH. P. fumosoroseus FG340 showed high mortality as 90% at 45% RH and 100% at 75% RH 6 days after conidia treatments. These results suggest that P. fumosoroseus FG340 and M. anisopliae FT83 have high potential to develop as a biocontrol agent against the beet armyworm.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.125-129
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• 2009

Entomopathogenic fungi were isolated directly from a cadaver of adult Monochamus alternatus supporting fungal sporulation, using a semi-selective medium and then screened several fungal colonies. The pathogenicity of each fungus was tested using oak longicorn beetle, Moechotypa diphysis, as substitutive insect. As the result, only one of them showed high pathogenicity against M. diphysis, with up to 100% mortality within 21 days of inoculation. Selected fungus was named as MaW1 and identified by Beauveria bassiana using microscopic examination and DNA analysis. Pathogenicity was also evaluated to M. alternatus.

• International Journal of Industrial Entomology and Biomaterials
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• 제17권2호
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• pp.211-215
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• 2008

To select entomopathogenic fungi controlling aphids effectively, several isolates were screened against second instars of Myzus persicae nymphs in the glasshouse using conidia suspension at $1.0{\times}10^5$ conidia/ml. Among these isolates, SFB-205 conidia showed the highest insecticidal activity about 32.7% efficacy to M. persicae at 4 days after application in the glasshouse. The attachment of SFB-205 conidia on the surface of M. persicae nymphs, and germination and penetration were observed using scanning electron microscopy. SFB-205 was identified as Beauveria bassiana species through the comparison of 5.8 s rRNA genes. There were 24 polymorphisms between SFB-205 and the previously reported isolate, B. bassiana ATCC74040 using six kinds of primer combinations in amplified fragment length polymorphism (AFLP) analysis. The B. bassiana SFB-205 might be used as a practical biological control agent for the green peach aphid, M. persicae in the field.

• 아시안잔디학회지
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• 제11권3호
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• pp.185-191
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• 1997

Biological control of turfgrass insect pest Blitopertha orientalis, forest insect pests, Agelastica coerulea, Meganola melancholia, and Glyphodes perspectalis,vegetable insect pests, Plutella xylostella and Agrotis segetum were conducted with entonopathogenic fungus, Metarhizium anisopliae J-22 isolated from black pine forest soil in Cheju province. Mortality of B. orientalis larvae was 53.3% at the rate of 3.4 $\times$ 1O 7 conidia /ml. A. coerulea and M melancholia larvae showed 100% mortalities at 9.6 $\times$ 106 conidia /ml and 2.7 $\times$ 10 7 conidia /ml as well. However, G. perspectalis larvae were not dead even at 4$\times$ 1O 7 conidia /ml. On the other hand, M anisopliae J-22 was effective against P. xylostella larvae showing 100% mortality at 4 $\times$ 10 7 conidia /ml. KEy words:Entomopathogenic fungi, Biological control, Metarhizium anisopliae, Pathogenicity,Blitopertha orientalis, Agelastica coerulea, Meganola melancholia, Glyphodes perspectalis,Plutella xylostella, Agrotis segetum.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.284-286
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• 1998

A ura5 gene encoding Orotate Phosphoribosyl Transferase (OPRTase) of Metarhizium anisopliae was cloned by PCR methods and sequenced. The sequenced ura 5 gene encodes a polypeptide of 234 amino acid residues. This deduced amino acid sequence showed high similarity to other fungi OPRTase and there was no intron sequence between ATG starting codon and TGA ending codon.

• 한국식물병리학회지
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• 제12권2호
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• pp.245-250
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• 1996

식물병원균 Botrytis cinerea와 Fusarium oxysporum에 대한 생물학적 방제의 기초자료를 얻기 위하여 살충성 진균 Beauveria bassiana의 식물병원균에 대한 균사성장저해, 포자발아 억제, 균사와 포자의 형태변화 등의 효과를 살펴보았다. 평판배지 상에서 두 식물병원균의 균사생장이 저해되었으며, 저해효과는 배지종류에 따라 달랐는데 B. cinerea의 경우 PDA배지에서 가장 크게 저해되었으며 F. oxysporum의 경우에는 TSA배지에서 가장 크게 저해되었다. B. bassiana는 $25^{\circ}C$에서 6일간 배양했을 때 F. oxysporum에 대한 항균력이 가장 높았으며 동시에 최대의 균체량을 생산하였다. 또한 B. bassiana의 배양여액을 식물병원균에 30% 농도로 첨가하여 배양했을 때 식물병원균의 포자 발아율은 B. cinerea, F. oxysporum에서 각각 30%(control: 88.2%), 10.0%(control: 78.6%)로 낮아졌으며 발아 개시 시간도 4~8시간 지연되었다. 현미경을 통한 미세구조관찰에서는 10%의 B. bassiana배양여액을 첨가했을 때 F. oxysporum의 포자 크기가 1/2~1/3으로 줄어들었으며 균사와 격막의 형태도 비정상적으로 변하여 균사외막과 격막-격막 사이의 구분이 불명확해졌다.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2008년도 추계학술발표회
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• pp.503-504
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• 2008

• International Journal of Industrial Entomology and Biomaterials
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• 제3권1호
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• pp.105-108
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• 2001

The wild entomopathogenic fungi, Cordyceps militaris, were collected at the Whawang mountain, Korea. The pupae of the silkworm, Bombyx mori, were used as infecting hosts for the production of the silkworm-mili-taris dongchunhacho, silkworm vegetable wasps and plant worms with C. militaris. Three inoculation methods in terms of injection, spray and immersion were tested against the silkworm pupae. The three inocu1ation methods revealed 100% infectivity to the silkworm pupae tested. Of the three inoculation methods, the injection method was highly effective in the reduction of the period required for the endosclerotium and the completion of fruiting body formation. These results indicate that the silkworm pupae are very effective host insects for the production of C. militaris.

• International Journal of Industrial Entomology and Biomaterials
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• 제31권1호
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• pp.20-24
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• 2015

Increased use of rhinoceros beetles (Allomyrina dichotoma ) for food and medicine, and their elevated value as pets has led to an increase in the number of their breeding farms. Mass breeding of the insects in these farms leads to entomological diseases. In this study, we investigate cannibalism resulting from overcrowded breeding of A. dichotoma larvae, as well as secondary fungal infections in epidermal wounds in the surviving larvae. Some of the fungi detected in the present study showed entomopathogenicity, and the larvae showed different times of death. In particular, larvae infected with Clonostachys sp., an endophytic plant fungus, grew for a long time after infection, but died without pupating.

• Mycobiology
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• 제41권4호
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• pp.221-224
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• 2013

Aphids are one of the most destructive pests in crop production such as pepper, cucumber, and eggplants. The importance of entomopathogenic fungi as alternative pest control agents is increasing. Conidia of entomopathogenic fungi are influenced by environmental conditions, such as temperature and relative humidity, and cause slow and fluctuating mortality. These factors have prevented wider application and use of biocontrol agents. For investigation of means of mitigation of such problems, we conducted bioassays with 47 fungal culture filtrates in order to evaluate the potential of secondary metabolites produced by entomopathogenic fungi for use in aphid control. Among 47 culture filtrates cultured potato dextrose broth, filtrate of Beauveria bassiana Bb08 showed the highest mortality (78%) against green peach aphid three days after treatments. Filtrate of Bb08 cultured in Adamek's medium showed higher toxicity as 100% to third instar nymphs of the aphid compared with seven other filtrates cultured in different broths amended with colloidal chitin or oil. The culture filtrates and fungal cultures from media amended with colloidal chitin or oil had lower control efficacies than filtrates without these additives in three different media. These results indicate that the fungal culture fluid or culture filtrate of B. bassiana Bb08 cultured in Adamek's medium has potential for development as a mycopesticide for aphid control.