• Proceedings of the PSK Conference
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• 2002.10a
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• pp.272.1-272.1
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• 2002

We have carried out collaborative study to evaluate a preparation of antithrombin concentrate whether or not it was suitable to serve as the candidate for a Korea National Biological Standard. Six laboratories. including three manufacturers and three National Control Laboratories. participated in this study. The potency of this candidate preparation was determined using the heparin cofactor chromogenic method. (omitted)

• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.136-143
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• 2007

Despite the increased interests in biological control of soilborne diesease for environmental protection, biological control of bacterial wilt caused by Ralstonia solanacearum have not provided consistent or satisfying results. To enhance the control efficacy and reducing the inconsistency and variability, combinations of specific strains of microorganisms, each having a specific mechanism of control, were applied in this study. More than 30 microorganisms able to reduce the activity of pathogen by specific mechanism of action were identified and tested for their disease suppressive effects. After in vitro compatibility examinations, 21 individual strains and 15 combinations were tested in the greenhouse. Results indicated three-way combinations of different mode of control, TS3-7+A253-16+SKU78 and TS1-5+A100-1+SKU78, enhanced disease suppression by 70%, as compared to 30-50% reduction for their individual treatments. This work suggests that combining multiple traits antagonizing the pathogen improve efficacy of the biocontrol agents against Ralstonia solanacearum.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.289-294
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• 2006

Two isolates of mucous bacteria, mc75 and pc78, were isolated from fungal culture plate as culture contaminants with an interesting swarming motility. Both isolates were identified as Pseudomonas fluorescens based on microscopy, biochemical analysis, Biolog test and DNA sequence analysis of the 16S rRNA gene. Both strains have the exactly the same 16S rRNA gene sequences, and yet their biological control activity were not identical each other. In vitro analysis of antagonistic activity of two isolates against several plant pathogenic fungi indicated that both produced diffusible and volatile antifungal compounds of unknown identities. Treatment of the bacterial culture of P. fluorescens pc78 and its culture filtrate exhibited a strong biological control activity against rice sheath blight in vivo among six plant diseases tested. More effective disease control activity was obtained from treatment of bacterial culture than that of culture filtrate. Therefore, in addition to antifungal compound and siderophore production, other traits such as biofilm formation and swarming motility on plant surface may contribute to the biological control activity of P.fluorescens pc78 and mc75.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2005.04a
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• pp.74.1-74.1
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• 2005

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.39-45
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• 2021

To establish the environmentally friendly biological control of two-spotted spider mites (TSSM), Tetranychus urticae, in exported strawberry greenhouses, the TSSM density reduction efficiency of chemical and biological control measures was compared in commercial, exported strawberry greenhouses. In the biological control greenhouse, only Phytoseiulus persimilis, a natural enemy of TSSM, was released, and the chemical control greenhouse was only sprayed with commercial chemical pesticides. The density of each developmental stage of TSSM was higher in the chemical control greenhouse than in the biological control greenhouse. The management costs were lower for the biological control greenhouse than the chemical control greenhouse. These results suggest that it is possible to effectively control TSSM using P. pesrsimilis in exported strawberry greenhouses.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1994.06a
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• pp.1-10
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• 1994

Biological control of plant disease has been considered a potential control strategy in integrated pest management in recent years. This paper reviewed the progress of research on the biological control of plant diseases in Korea during the last two decades and adopts some future prospects. The crop diseases included, red pepper, Phytophthora blight, ginseng root rots cucumber wilt, sesame damping-off, strawberry wilt and tobacco bacterial wilt and mosaic. Biological control of plant diseases requires a multi-disciplinary approach involving input from plant pathologists, ecologists, mycologists and molecular biologists. The author proposed to organize a group“Committee for Biological Control”including researchers, industries, growers and administrators.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.8-23
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• 2011

Weeds are one of the major constraints to crop production in organic farming systems. This paper reviews major results and techniques achieved with physical, cultural, and biological weed control and their perspectives in organic agriculture. Physical methods includes mechanical, thermal, lighting, electrocution, pneumatic, autonomous robot weeding control techniques. Cultural weed control methods includes mulching, tillage, crop rotation, cover crops and crop competition. Physical and cultural weed control techniques are especially important in organic farming crops where other weed control options are limited or not available without use of herbicides. Biological weed control includes mycoherbicides, innundative biological control, broad-spectrum biological control and allelopathy. Successful weed management in organic farming requires well managed integrated systems of mechanical control using newly developed machines, cultural control and biological control methods. Weed management decision-aid models may also needed to develop to provide greater assurance of achieving profitability and appropriate long-term weed management in organic farming in the future.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2457-2460
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• 2003

There is a great demand to manipulate biological cell autonomously since biologist should spend much time to obtain skillful manipulation techniques. For this purpose, we propose a cell chip to control, carry, fix and locate the cell. In this paper, we focus on the cell rotator to rotate individual biological cell based on a micro fluidics technology. The cell rotator consists of injection hole and rotation well to rotate a biological cell properly. Under the variation of flow rate in injection hole, the angular velocity of a biological cell is evaluated to find the feasibility of the proposed rotation method. As a practical experiment, Zebrafish egg is employed. Based on this research, we find the possibility of non-contact rotation way that can highly reduce the damage of the biological cell during manipulation. To realize an autonomous biological cell manipulation, a cell chip with manipulation well and micro channel in this research will be utilized effectively in near future.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.701-709
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• 2005

An efficient method of selecting an antagonistic strain for use as a biological control agent strain was developed. In this improved method, the surface tension reduction potential of an isolate was included in the 'decision factor,' in addition to two other factors; the growth rate and pathogen inhibition. By using a statistically designed method, an isolate from the soil was selected and identified as Bacillus sp. GB 16. In the pot test, this strain showed the best performance among the isolated strains. The lowest disease incidence rate and fastest seed growth were observed when the Bacillus sp. GB 16 was used. The action of the surface tension reducing component was assumed to enhance the wetting, spreading, and residing of the antagonistic strain in the rhizosphere. This result showed that the improved selection method was quite effective in selecting the best antagonistic strain for the biological control of soilborne infectious plant pathogens.

• Sleep Medicine and Psychophysiology
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• v.5 no.1
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• pp.34-44
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• 1998

Living organisms are influenced by many external rhythms and they have adapted their physiology to periodically changing conditions. These adaptive strategies are controlled by endogenous innate programs of behavior and physiology which are determined by external signals ("Zeitgeber"). There are many biological rhythms, each with its own characteristic functional adaptation. Among them, the presence of endogenous time control of feeding and drinking becomes obvious. There are increasing evidences that the control of food intake, food selection, and drinking are regulated by the endogenous rhythms including a circadian rhythm. However, there have been many restrictions in understanding the endogenous control of food intake itself and its mechanism. To broaden our know ledges of the endogenous time control of feeding and drinking, the author reviwed the characteristics of the endogenous timing for food intake, the influence of circadian pacemakers and food-entrainable oscillators, the interaction between the circadian control and the external and internal conditions in the control of food intake, the conseqences of feeding, the circadian control of food selection, and the biological cycles in energy balance.