• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.1-7
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• 1998

In order to find relationship within and between entomopathogenic species, analysis of protein band pattern in mycelia of 25 isolates was conducted by UPGMA. The results allowed differentiation of three groups on 85% similarity coefficient. Similarity coefficient within C. militaris was $0.787{\sim}1.000$, C. kyushuensis was 0.958-1.000 and C. pruinosa was 0.993-1.000. C210 and C298 isolates which had somewhat immersed perithecia, comparable to other C. militaris isolates, had 91% similarity. C108, C225-1 and C228 isolates pathogenic on Lepidopterous larvae had 89% similarity. Closely related species to C. militaris were C. kyushuensis and C. pruinosa. And similarity between C. pruinosa and C. kyushuensis was 88%. Similarity between C. bifusispora formed conidia on media and Paecilomyces tenuipes was 89%. C. scarabaeicola pathogenic specifically on adult Scarabaeidae had 82% similarity with above two species. C118 identified as C. militaris showed different protein banding patterns.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.906-909
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• 2001

In order to investigate fatty acid contents and effects of cell growth on the production of an extracellular protease and toxicity of exotoxin, several symbiotic bacteria with highly effective toxins were isolated from seven species of entomopathogenic nematodes belong in Steinernematidae(Steinernema glaseri XR-DR, S. glaseri XR-NC, S. glaseri XR-MK, S. carpocapsae XR-PC, S. maticola XR-MO, S. Longicaudum XR-LC) and Heterorhabditidae sp.(Heterorhabditis bacteriophora XR-HY). In the cell growth and exotoxin toxicity, XR-PC and XR-MK were superior to other species when cultured in vitro. The protease activity of XR-DR was remarkable compared to other species. In the case of XR-HY, the protease activity increased in parallel with cell growth. Interestingly the fatty acid contents of XR-PC and XR-HY were significantly different from those of other species 12:0, 14:0, 13:0 iso, 16:1 cis 5 and 17:0 cyclo.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.171-179
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• 2000

- Turfgrass insect pests and natura.l enemies for biological control were investigated to develop pest management effectively in golf courses at several golf clubs. Twenty eight insect pest species of 10 families in 6 orders were collected from golf courses. The zoysiagrass mite, Eriophyes zoysiae and root-knot nematode, Meloidogyne incognita were also collected from zoysiagrass. White grubs of several scarab beetles and cutworms (Agrotis spp.) damaged seriously at most surveyed golf clubs. In addition, bluegrass webworm (Crambus sp.), Japanese lawngrass cutworm (Spodoptera depravata), scale insects, Tipula sp., and ants (Camponitus japonicus, Formica japonica, and Lasins japonicus) damaged turfgrasses directly or indirectly in golf courses. The entomopathogenic nematodes, Heterorhabditis spp., Steinernema glaseri, and S. longicaudum, entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, and milky disease, Paenibacil/us popil/iae were isolated from white grubs or turfgrass soil as microbial control agents. Besides, dipteran predators, Cophinopoda chinensis, Philonicus albiceps, and Promachus yesonicus and hymenopteran parasitoid, Tiphia sp. were also collected. The P. yesonicus was the most active in golf courses. The root-knot nematode, M. incognita was found from Zoysia japonica, Z. matrella. and Cynodon dactylon.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.145-152
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• 2003

Field application of the entomopathogenic nematode, Steinernema carpncapsae, is limited by its susceptibility to UV irradiation and desiccation especially at leaf spray control. This study was conducted to develop the control technique using alginate biocapsulation of the nematodes against the beet armyworm, Spodoprera exigua and the tobacco cutworm, Sp. litura that are normally infesting hosts above ground level. The alginate capsules including infective juveniles gave significant feeding toxicities to the larvae of the two lepidopteran species. The lethality followed a typical sigmoid dose-mortality pattern with increase of the nematode densities embedded in the capsules. Moisture content in the capsule was critical to the survival of the infective juveniles. More than 80% nematodes could survive above 10% moisture content remained in the capsule. Remaining moisture content within the capsule was dependent on relative humidity, ambient temperature, and capsule size, but not on citric acid reaction time during capsule formation. More than 80% of infective juveniles in the alginate capsules could survive in distilled water at 15$^{\circ}C$ for 60 days. When these nematode capsules containing welsh onion extract as another phagostimulant were applied on the 3rd instar larvae of Sp. exigua infesting peanut plants, they resulted in about 90% control efficacy. These results indicate that the alginate capsulation can be used for leaf-spray agent of the entomopathogenic nematodes as well as for improved storage purpose.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.255-260
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• 1999

Pathogenicity and multiplication of entomopathogenic nematode, Steinernema carpocapsae Weiser, ere analyzed in two insect hosts, Spodoptera exiga (Hubner) and Sp. litura(Fabricius). The estimated ${LC}^{50}s$(lethal concentration of the infective juveniles to kill 50% of the host insect population) were not different between tow insect species or among their developmental stages on the filter paper assay, thought the actual numbers of the infected nematodes were varied among them. The significant variation, however occurred in nematode multiplication between tow inset hosts. Temperature also gave sosignificatn effect on nematode multiplication rate that it took 6 days after infection at $25^{\circ}C$, but did 12 days at $20^{\circ}C$ to show the maximal nematode population peak($\approx$500,000 infective juveniles(IJ) in a 5th instar larva of Sp. litura and $\approx$-100,000 IJ in a 5th instar larva of Sp. exigua).

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.300-303
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• 2010

Laboratory trial on the control effect of Beauveria bassiana against Paratlanticus ussuriensis was carried out with fungi collected from South Korea, China and Peru. All B. bassiana species from collected at each site had a strong fungicidal activity against P. ussuriensis. The Abbott's formula was the highest showing 100% mortality and the others also showed over 60% mortality. It took 3 to 6 days until katydid attained to death after inoculation with all B. bassiana treatments. From this trial, B. bassiana fungus was found to have some effects as pathogenicity of entomopathogenic activity against P. ussuriensis. So B. bassiana could be considered as one of the environment-friendly and effective pesticides for the control of P. ussuriensis.

• Mycobiology
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• v.48 no.2
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• pp.139-147
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• 2020

Root-feeding Scarabaeidae, particularly white grubs are considered among the most harmful coleopteran insect pests in turfgrass. In this work, sixteen entomopathogenic fungal species were assayed against flower chafer beetle, Protaetia brevitarsis (Coleoptera: Scarabaeidae) and Metarhizium anisopliae JEF-314 showed high virulence. The control ability of the isolate JEF-314 has been in detail tested for a model insect flower chafer beetle. Further analyses showed insect stage-dependent virulence where the fungal virulence was the highest against smaller instar larvae. Additionally, we confirmed that millet-based solid cultured granule was effective against the soil-dwelling larval stage. The isolate also showed a similar ability for a representative pest (Popillia spp.) in laboratory conditions. Our results clearly suggest a high potential of M. anisopliae JEF-314 to control the flower chafer beetle, possibly resulting in controlling of root-feeding white grubs in turfgrass. Based on the insect life cycle and susceptibility to the fungus, late spring and summer time would be the optimum time to apply JEF-314 granules for an effective control. Further characterization of the efficacy of the fungus under field conditions against the Scarabaeidae beetles might provide an efficient tool to control this beetle in an environment-friendly way.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.6
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• pp.440-446
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• 2004

Interest in in vitro study of entomopathogenic fungi, including Cordyceps species, has been increasing due to their valuable bioactive compounds and biocontrol effects. Among Cordyceps species, in vitro stromata of C militaris has been successfully produced and cultivated for industrial purposes. However, genetic study on in vitro stromata formation of C militaris has not been carried out yet. Here, relationship between mating system and perithecial stromata formation of C militaris is reported. Mating system was determined by observing perithecial stromata formation from mono-ascospore cultures and their pair-wise combinations. Certain combinations of mono-ascospore strains produced perithecial club-shaped stromata, whereas other combinations produced either no stromata or only abnormal non-perithecial stromata. Similarly, mono­ascospore cultures without combination produced either no stromata or only abnormal non­perithecial stromata. Despite obvious heterothallism, self-fertility was occasionally observed in few strains of C militaris. These observations indicated that C militaris behaves as a bipolar het­erothallic fungus and requires two mating compatible strains in order to produce regular club­shaped perithecial stromata, a fundamental requirement for its industrial cultivation.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.968-978
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• 2007

A pathogenic nematode, Butlerius sp., was isolated from Oriental beetle, Blitopertha orientalis. The infective juveniles exhibited dose-as well as time-dependent entomopathogenicity on the larvae of B. orientalis. Two bacterial species, Providencia vermicola (KACC 91278) and Flavobacterium sp. (KACC 91279), were isolated from the infective juveniles and identified. P. vermicola outnumbered Flavobacterium sp. in the nematode host, in which the colony density of P. vermicola was found to be 21 times higher than that of Flavobacterium sp. However, when the two bacterial species were cocultured in culture media without the nematode host, they showed similar growth rates. Both bacteria induced significant entomopathogenicity against Spodoptera exigua larvae infesting economically important vegetable crops, where P. vermicola was more potent than Flavobacterium sp.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.377-383
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• 2009

This study was conducted to investigate the total phenol contents, antioxidative activities and antibacterial activities of twenty species of entomopathogenic fungi. The total phenol content was highest in Aspergillus flavus ($553.0{\pm}52.15{\mu}g/g$) and A. parasiticus ($529.9{\pm}60.10{\mu}g/g$). On the other hand those in other strains were within the range of $26.6{\sim}121.9{\mu}g/g$. The antioxdative activity was shown in the most of strains and the highest DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical scavenging activity was observed in A. flavus ($90.9{\pm}2.90%$) and A. parasiticus ($77.9{\pm}4.13%$). This result indicated that the antioxidative activities were very correlated with the total phenol contents. The antibacterial activitiy was found in the every tested pathogenic bacteria. Especially, the antibacterial activity was strongest against Listeria monocytogenes and Escherchia coli.