• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.32-37
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• 2007

The study was carried out to establish buffer zone for the protection of the non-target organisms by aerial pesticide application. The two pesticide combination of 3-way tank-mixing of three pesticides for aerial application, ferimzone tricyclazole SC + BPMC EC + validamycin-A SL and hexaconzole EC + isoprothiolane EC+phenthoate EC were selected for the simultaneous control of key pests on paddy rice as blast, sheath blight, brown planthopper and moth. Aquatic organisms including killifish and loach in the paddy field and nearby water reservoirs were not affected by aerial application of the pesticides. However, all the water flea were killed, when they were exposed 10 m from the aerially sprayed site, while the water flea exposed in 30 m away from the site were not affected. Honeybees within 50 m in the wind direction and 20 m in the opposite wind direction showed a mortality of $7{\sim}100%$. Residues concentration of the pesticides in paddy water were not detectable level after six days from aerial application. Drifting distance of aerially sprayed droplet from the target area was within 30 m in the wind direction and 20 m in the opposite direction. Consequently, it was the buffer zones in the aerial pesticides application for the protection of the non-target organisms should be at least 50 m for aquatic organisms and 100 m for honeybees.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.47-57
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• 1996

병원성 Fusarium에 의한 아스파라거스 감염은 비병원성 Fusarium을 5일과 7일 전에 접종하였을 때 방제효과가 있었다. 비병원성 F. oxysporum은 F. moniliforme에 대하여 방제효과가 있었고, F. solani는 F. oxysproum에 대하여 방제효과가 있음이 밝혀졌다. 실험에 사용된 Fusarium 균들은 모두 주근과 측근의 말단 부위, 상처부위, 그리고 표피의 세포벽 사이를 통하여 감염하였다. 경우에 따라 감염하는 동안 appressorium과 유사한 구조를 형성하기도 하였고, 직접 감염하는 경우도 있었다. 병원성 그리고 비병원성 Fusarium 균 모두 공통적으로 생장점 부위를 통하여 감염하였다. 병원성이 강한 Fusarium 균의 경우 비병원성 균들보다 감염의 속도가 빨랐고 더욱 생장이 왕성하였다. F. solani는 생장속도나 기주 조직 침입속도가 매우 느렸다. 기주 감염의 결과 처음에는 cortical rot을 유발시켰고 나중에는 tracheary elements를 감염하고 결국은 조직의 괴사를 유발하는 것이 관찰되었다. 비병원성 F. oxysporum은 표피조직에 두터운 균사층을 형성하였고, 이는 병원성 Fusarium 균에 대한 방제효과를 나타내는 원인을 제공한 것으로 여겨진다. F. solani는 측근의 생성을 촉진시켜 표면적을 증대시킨 것으로 여겨진다. 결론적으로 AVFO와 F. solani를 이용하여 아스파라거스에 발생하는 병원성 Fusarium균의 침입을 저지할 수 있는 생물적 방제가 가능함이 밝혀졌다.

• Research in Plant Disease
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• v.13 no.3
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• pp.197-203
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• 2007

An isolate of Ampelomyces quisqualis 94013(AQ94013) was selected as an effective parasite for biological control of cucumber powdery mildew. In the greenhouse, occurrence of cucumber powdery mildew was significantly suppressed for nine days by pre-treatment with $5.0{\times}10^6/ml$ and $5.0{\times}10^7/ml$ of conidial suspension of AQ94013. The disease was effectively controlled within three to seven days by post-treatment with the $5.0{\times}10^6/ml-conidial$ suspension of AQ94013. When AQ94013 was treated at concentration of $5{\times}10^6/ml$ three times at seven-day interval in the vinylhouse, the control effect was higher than that treated twice at ten-day interval and that treated with fenarimol twice. As the results, Ampelomyces quisqualis 94013 could be a prospective biofungicide for biological control of powdery mildew of cucumber.

• 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.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2004.11a
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• pp.34-43
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• 2004

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2004.11a
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• pp.49-49
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• 2004

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.39-39
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• 2003

• Proceedings of the Korean Society of Soil Zoology Conference
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• 1998.10a
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• pp.21-21
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• 1998

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.47-48
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• 2005

• Research in Plant Disease
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• v.27 no.4
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• pp.129-136
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• 2021

Rice is responsible for the stable crop of 3 billion people worldwide, about half of Asian depends on it, and rice is grown in more than 100 countries. Rice diseases can lead to devastating economic loss by decreasing yield production, disturbing a stable food supply and demand chain. The most commonly used method to control rice disease is chemical control. However, misuse of chemical control can cause environmental pollution, residual toxicity, and the emergence of chemical-resistant pathogens, the deterioration of soil quality, and the destruction of biodiversity. In order to control rice diseases, research on alternative biocontrol is actively pursued including microorganism-oriented biocontrol agents. Microbial agents control plant disease through competition with and antibiotic effects and parasitism against plant pathogens. Microorganisms isolated from the rice rhizosphere are studied comprehensively as biocontrol agents against rice pathogens. Bacillus sp., Pseudomonas sp., and Trichoderma sp. were reported to control rice diseases, such as blast, sheath blight, bacterial leaf blight, brown spot, and bakanae diseases. Here we reviewed the microorganisms that are studied as biocontrol agents against rice diseases.