• Korean journal of applied entomology
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• v.40 no.3
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• pp.259-264
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• 2001

Toxicological studies of two potential biological control agents, the entomopathogenic nematode (Steinernema carpocapsae) and the symbiotic bacteria (Xenorhabdus nematophilus) were conducted against two beneficial insects and one mammal species. Two microbial agents varied in their toxicities between two insect species: an ant, Pristomyrmex pungens, and silkworm, Bombyx mori. In oral toxicity test, the symbiotic bacteria resulted in significant lethal [half lethal concentration of $1.4$\times$10^3$colony-forming units (cfu)/ml] on the ants, while they gave little lethal effect (half lethal concentration of more than $10^{8}$ cfu/ml) on the silkworms. The nematodes, however, gave significant lethal effect [half lethal concentration of 4 infected juveniles (IJs)/ml] on the silkworms, while they did little lethal effect (half lethal concentration of 150,000 IJs/ml) on the ants in topical assays. Both the nematodes and the bacteria did not give lethal effect to the albino rats, Rattus norvegicus, when they were fed orally into the rats. Also, any of these microbial agents were not detected in the internal organs of the treated rats.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.05a
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• pp.97-97
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• 2002

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.05a
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• pp.186-186
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• 2002

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.11a
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• pp.49-49
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• 2002

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.11a
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• pp.115-115
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• 2002

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.106-106
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• 2005

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2000.05a
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• pp.46-46
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• 2000

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2003.10a
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• pp.85-85
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• 2003

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.723-729
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• 2003

Xenorhabdus nematophilus Kor-Al was cultured at flask and 5L jar fermentor at $28^{\circ}C$, 5% YS media condition. Antibiotic activity for X. nematophilus Kor-Al was experimented by paper disk method. As the result, antibiotic activity was growth associated form during culture time of X. nematophilus Kor-Al at flask. The maximum production and antibiotic activity were obtained at stationary period of cell growth. The optimum conditions of cell growth and antibiotic production at 5L jar fermentor were 400rpm agitation and 50% DO conditions.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.435-445
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• 2008

Due to internal feeding behavior, the oriental tobacco budworm, Helicoverpa assulta ($Guen\acute{e}e$), infesting hot pepper has been regarded to be effectively controlled by targeting egg and neonate larval stages just before entering the fruits. This study aimed to develop an efficient biological control method focusing on these susceptible stages of H. assulta. An egg parasitoid wasp, Trichogramma evanescens Westwood, was confirmed to parasitize the eggs of H. assulta. A mixture of Gram-positive soil bacterium, Bacillus thuringiensis subsp. kurstaki, and Gram-negative entomopathogenic bacterium, Xenorhabdus nematophila ANU101, could effectively kill neonate larvae of H. assulta. A sex pheromone trap monitored the occurrence of field H. assulta adults. The microbial insecticide mixture was proved to give no detrimental effects on immature development and adult survival of the wasp by both feeding and contact toxicity tests. A combined treatment of egg parasitoid and microbial pesticide was applied to hot pepper fields infested by H. assulta. The mixture treatment of both biological control agents significantly decreased the fruit damage, which was comparable to the chemical insecticide treatment, though either single biological control agent did not show any significant control efficacy. This study also provides morphological and genetic characters of T. evanescens.