• Mycobiology
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• 제50권2호
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• pp.142-149
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• 2022

Orchids live with mycorrhizal fungi in mutualism. This symbiotic relationship plays an essential role in the overall life cycle of orchids from germination, growth, settlement, and reproduction. Among the 1000 species of the orchid, the Korean lady's slipper, Cypripedium japonicum, is known as an endangered species. Currently, only five natural habitats of the Korean lady's slipper remain in South Korea, and the population of Korean lady's slipper in their natural habitat is not increasing. To prevent extinction, this study was designed to understand the fungal community interacting in the rhizosphere of the Korean lady's slipper living in the native and artificial habitats. In-depth analyses were performed to discover the vital mycorrhizal fungi contributing to habitat expansion and cultivation of the endangered orchid species. Our results suggested that Lycoperdon nigrescens contributed most to the increase in natural habitats and Russula violeipes as a characteristic of successful cultivation. And the fungi that helped L. nigrescens and R. violeipes to fit into the rhizosphere community in Korean lady's slipper native place were Paraboeremia selaginellae and Metarhizium anisopliae, respectively. The findings will contribute to restoring and maintaining the endangered orchid population in natural habitats.

• 한국토양동물학회지
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• 제9권1_2호
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• pp.1-5
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• 2004

2002년에서 2004년까지 3월에서 11월 사이에 무궁화를 가해하는 해충과 천적에 관해 조사한 결과 해충은 5목 9과 12종, 비곤충류 2목과 2과 2종이 조사되었다. 목별로는 매미목(Homoptera) 5종과, 나비목(Lepidoptera) 3종, 딱정벌레목(Coleoptera) 2종, 메뚜기목(Orthoptera) 1종, 노린재목(Hemiptera) 1종, 응애목(Acarina) 1종, 병안목(Stylommato-phora) 1종이 조사되었다. 무궁화 해충 중 목화진딧물, 무궁화잎밤나방 그리고 점박이응애등이 피해가 심하여 방제를 요하는 주요해충이었다. 목화진딧물은 5월~6월, 무궁화잎 밤나방은 7월~8월, 점박이응애는 6월~8월에 밀도가 높았다. 무궁화에서 발견된 천적 및 병원성 미생물은 세균 1종, 병원성 곰팡이 3종, 노린재목 1종, 딱정벌레목 1종, 벌목 1종 파리목 2종, 응애강 1종 등 11종이 조사되었다. 목화진딧물 포식성 천적은 진디혹파리(Aphidoletes aphidimyza), 꽃등에류(Eristalis sp.), 무당벌레(Harmonia axyridis), 기생성 천적은 싸리진디벌(Aphidius gifuensis), 병원성 미생물은 Verticillium lecanii, Beauveria bassinan가 조사되었다. 무궁화잎밤나방 기생성 천적은 고치벌류(Cotesia sp.), 병원성 미생물은 Bacillus thuringiensis, B. bassiana, Meterhizium anisopliae가 확인되었다. 점박이응애 포식성 천적은 긴털이리응애류(Amblyseius sp.), 애꽃노린재류(Orius sp.)가 조사되었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제26권2호
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• pp.89-94
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• 2013

Entomopathogenic fungal species have been investigated for their potential use as biological control agents owing to their natural role as insect pathogens. These fungi produce a wide range of secondary metabolites with high therapeutic values, such as antibiotics and cytotoxic substances. To evaluate the antibacterial activity of entomopathogenic fungi, 10 isolates from Korean soil were selected and tested for their activity against Escherichia coli by using fungal culture filtrates. Antibacterial activity was assessed using a two-step process: (1) a screening assay for the selection of fungal isolates and (2) a quantitative assay to evaluate the activity of select fungi. Although 4 fungal isolates were selected through the screening assay, only 3 fungal isolates, from Beauveria bassiana and Metarhizium anisopliae, showed high antibacterial activity according to the quantitative assay. The antibacterial activity of selected fungal culture filtrates was stable when exposed to heat and proteolytic enzyme treatments, which indicated that the antibacterial compound is not a protein. These entomopathogenic fungal metabolites might be useful as a source for bacterial control and in the pharmaceutical industry.

• International Journal of Industrial Entomology and Biomaterials
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• 제30권2호
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• pp.64-74
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• 2015

Beetles Protaetia brevitarsis seulensis Kolbe (Coleoptera: Cetoniidae) and Allomyrina dichotoma Linn. (Coleoptera: Scarabaeidae) are widely used in traditional medicine, and the number of insect-rearing farms is increasing in South Korea. The purpose of this study was to establish a multiplex PCR-based assay for rapid simultaneous detection of multiple pathogens causing insect diseases. Six insect parasites such as fungi Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) and Metarhizium anisopliae (Metschn.) Sorokin (Hypocreales: Clavicipitaceae), bacteria Bacillus thuringiensis Berliner (Bacillales: Bacillaceae), Pseudomonas aeruginosa Migula (Pseudomonadales: Pseudomonadaceae), and Serratia marcescens Bizio (Enterobacteriales: Enterobacteriaceae), and Oryctes rhinoceros nudivirus were chosen based on the severity and incidence rate of insect diseases in South Korea. Pathogen-specific primers were designed and successfully applied for simultaneous detection of multiple infectious agents in farm-bred insects P. b. seulensis and A. dichotoma using multiplex PCR and high resolution capillary electrophoresis. Our results indicate that multiplex PCR is an effective and time-saving method for simultaneous detection of multiple infections in insects, and the QIAxcel capillary electrophoresis system is useful for quantitative evaluation of the individual impact of each infectious agent on the severity of insect disease. The approach designed in this study can be utilized for rapid and accurate diagnostics of infection in insect farms.

• International Journal of Industrial Entomology and Biomaterials
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• 제33권1호
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• pp.1-5
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• 2016

Beauveria bassiana is a common fungal pathogen of Protaetia brevitarsis larvae, and although it is less common than Metarhizium anisopliae , the pathogen still poses a great risk to humans and animals that consume infected insects, owing to B. bassiana's production of toxins like beauvericin and mycotoxin. Interestingly, the beneficial microorganism Saccharomyces cerevisiae possesses antifungal properties. In the present study, we found that S. cerevisiae inhibited the growth of B. bassiana by 97% and that S. cerevisiae failed to harm P. brevitarsis when administered via intracoelomic injection (1×10⁷ cfu/mL). In addition, we also found that S. cerevisiae consumption increased the survival time of percutaneously infected P. brevitarsis larvae by 5 d and reduced the mortality of infected larvae by 12%. Therefore, S. cerevisiae is expected to be useful in the prevention and control of B. bassiana in the production of P. brevitarsis larvae.

• Mycobiology
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• 제45권3호
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• pp.192-198
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• 2017

The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.

• Journal of Microbiology
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• 제44권6호
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• pp.622-631
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• 2006

In this study we purified a fibrinolytic enzyme from Cordyceps militaris using a combination of ion-exchange chromatography on a DEAE Sephadex A-50 column, gel filtration chromatography on a Sephadex G-75 column, and FPLC on a HiLoad 16/60 Superdex 75 column. This purification protocol resulted in a 191.8-fold purification of the enzyme and a final yield of 12.9 %. The molecular mass of the purified enzyme was estimated to be 52 kDa by SDS-PAGE, fibrin-zymography, and gel filtration chromatography. The first 19 amino acid residues of the N-terminal sequence were ALTTQSNV THGLATISLRQ, which is similar to the subtilisin-like serine protease PR1J from Metarhizium anisopliae var. anisopliase. This enzyme is a neutral protease with an optimal reaction pH and temperature of 7.4 and $37^{\circ}C$, respectively. Results for the fibrinolysis pattern showed that the enzyme rapidly hydrolyzed the fibrin $\alpha$-chain followed by the $\gamma$-$\gamma$ chains. It also hydrolyzed the $\beta$-chain, but more slowly. The A$\alpha$, B$\beta$, and $\gamma$ chains of fibrinogen were also cleaved very rapidly. We found that enzyme activity was inhibited by $Cu^{2+}$ and $Co^{2+}$, but enhanced by the additions of $Ca^{2+}$ and $Mg^{2+}$ ions. Furthermore, fibrinolytic enzyme activity was potently inhibited by PMSF and APMSF. This enzyme exhibited a high specificity for the chymotrypsin substrate S-2586 indicating it's a chymotrypsin-like serine protease. The data we present suggest that the fibrinolytic enzyme derived from the edible and medicinal mushroom Cordyceps militaris has fibrin binding activity, which allows for the local activation of the fibrin degradation pathway.

• 한국균학회지
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• 제25권4호통권83호
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• pp.239-252
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• 1997

1990년 부터 1996년까지 16개소의 채집지에서 채집되어 분류동정된 동충하초는 12속 33종으로 이중 Cordyceps bifusispora, C. martialis, C. oxycephala, C. paludosa, C. pentatomi, C. rosea, C. ryogamiensis, Shimizuomyces paradoxa, Akanthomyces aculeatus, Polycephalomyces ramosus, Tilachlidiopsis nigra 등 14종은 국내 미기록종이다. 주로 다수 채집된 동충하초인 C. nutans, C. specocephala, Paecilomyces tenuipes 등은 전 채집시기에 걸쳐 고루 분포하였다. C. mizitayis C. kyushuensis, C. pruinosa 등과 같이 자실체의 발생이 환경조건으로서 대기내 습도에 강하게 영향을 받는 종들의 경우는 주로 장마철이 시작되면서 상대습도가 높아지는 7월 중순부터 8월 중순까지 분포하는 것으로 나타났다. 채집된 동충하초중 분리된 종은 C. bifusispora를 포함하여 Cordyceps속 9종, 불완전 균류의 Beauveria bassiana, Metarhizium anisopliae, Paecilomyces tenuipes, Verticillium lecanii등 총 13종이며, 분리된 Cordyceps속 동충하초를 이용하여 완전세대와 불완전세대의 관계를 구명한 결과 C. militaris와 C. kyushuensis는 Verticillium속으로, C. pruinosa는 Acremonium속으로, C. sphecocephala는 Hymenostilbe속으로, C. scarabaeicola는 Beauveria속으로 각각 밝혀졌다.