• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.40-40
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• 2005

• Journal of Sericultural and Entomological Science
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• v.40 no.1
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• pp.63-69
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• 1998

Twenty seven out of ca. 5,000 actinomycete strains, which were isolated from soil collected throughout the country, showed antibicrobial effects against fungai, Rhizopus stronifer (ATCC 6227a), Rhizoctonia solani (KCCM 11271) and yeast, Candida albicans (ATCC 10231). From these antifungal microorganisms, we further selected seven strains which seemed to produce insecticidal substances with in vivo test, using silkworm, Bombyx mori and beet armyworm, Spodoptera exigua. Morphological and biochemical experiments revealed that three strains out of seven were Streptomyces. Further investigations on the physical and chemical properties of these antifungal and insecticidal substances are now in progress.

• Journal of Environmental Health Sciences
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• v.23 no.1
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• pp.66-73
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• 1997

This procedure describes the method for gas chromatographic determination of 31 organophosphorus and 28 organochlorine pesticides in 10g of spinach, tomato and onion. After the pesticides were extracted with several solvents, the amount of coextractives and recovery rates of acephate and methamidophos were calculated. Samples for organochlorine pesticides were cleaned up with florisil solid phase extraction columns. NaBH$_4$ was added to onion extracts, which contained sulfur compound. All the concentrated extracts were analyzed by gas chromatography with ECD and NPD. The smallest amount of coextractives resulted from the spinach samples extracted with 5% MeOH in ethyl acetate. 5% EOH in ethyl acetate had the highest extractability for acephate and methamidophos and gave the best overall performance as an extraction solvent. The ability of 5% EOH in ethyl acetate to extract various organophosphorus and organochlorine pesticides from spinach, tomato and onion was examined. Recovery of 59 insecticides ranged from 58.0% to 110.5%. The average recoveries of fortified spinach, tomato and onion were 90.08%, 94.54% and 84.90%, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.203-205
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• 2003

Black sooty mould fungus was observed on the upper side of the mulberry leaves caused by the Capnodium sp. This fungus develops with the utilization of the honeydew dropped by the whiteflies. Few selected insecticides like Monocrotophos, Chloropyriphos and Nuvan were tried to control the whitefly incidence and followed by the application of Maida (wheat flour paste) and Starch solution separately to control the incidence of the Capnodium on mulberry. It is found that a significant control of the whitefly incidence with the application of Nuvan (2 $m\ell$/L) and followed by Chloropyriphos (2 $m\ell$/L) and Monocrotophos (1.6 $m\ell$/L) and also a significant control of sooty mould infection were recorded with Starch and Maida application.

• The Korean Journal of Pesticide Science
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• v.6 no.2
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• pp.51-57
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• 2002

Cyanogenic glycosides are secondary plant metabolites that are known as plant defense chemicals. They are found in cassava, bamboo, flax, and other plants. In this paper, the role of cyanogenic glycosides, their characteristics, and their interactions with insects are discussed. Previous and current research in our laboratory found that several natural and synthetic cyanohydrins were effective against stored-product insects as fumigants. Due to their insecticidal activity to insects, cyanohydrins can be used as an alternative fumigant and also as soil fumigants. Risk assessment, however, should be done to account for possible environmental problems, non-target wildlife effects, and human health effects.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.154-160
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• 2000

Aflatoxin B1 is known as the most potent mycotoxin produced by several fungi. It has been demonstrated to be not only carcinogenic but teratogenic and mutagenic as well in humans. To prevent or inactivate aflatoxins, several chemical of physical methods were tested for ammoniation, using insecticides as an wxample, but they were unsuitable for food products. On the contrary, biological control by antagonistic microorgani는 is and ideal method. In order to control aflatoxin B1 biologically, the antagonists #07, #63, #75, #74, and #61 were separated from various samples by using the antagonistic activity test. Among them, culture filtrate part A (non heat-treated) of #63 and #74 on aflatoxin B1 produced by Aspergillus fkavus were shown to be 95% and 75%, respectively. Based on the morphological characteristics, #63 was deduced as an Azospirillum sp.

• Korean journal of applied entomology
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• v.31 no.1
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• pp.69-78
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• 1992

The extensive cultivation of new yielding varieties might give some distruption to the rice insect pest complex in Korea The population of Nephottetix cincticeps and Laodelphax striatellus has decreased in number since the extensive cultivation of new varieties, Tongil lines, in 1976. During the last 23 years, the rice insect pest population except for Chilo suppressalis drastically decreased, however, C. suppressalis population increased again in recent years. This tendency seems to be very closely correlated with the cultivation of new varieties, and a lot of fertilizations and insecticides applications.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.107-116
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• 1997

Karyotype of apterous green peach aphid (Myzus persicae SuIBer) populations occurring in tobacco fields and their resistance to insecticides were investigated. All of the 16 clones collected from tobacco fields had same chromosome number of 2n=12. Among them, 5 clones had the normal karyotype, regardless of color morph, but chromosomal translnations between #1 and #3 autosomal chromosomes were noted in the other 11 clones. All of the aphid clones were highly resistant tolambda cyhalothrin, a pyrethroid pesticide, having over 20 times higher concentrations of LD90 than recommended concentration (10ppm) for the aphid. However, their resistance to acephate, demeton 5-methyl and pirimicarh varied depending on the clones, among which green-colored clones were generally more resistant to the pesticides than red-colored ones. No association was found between the insecticide resistance and the karyotype of the aphid in this experiment.

• Journal of Environmental Health Sciences
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• v.12 no.1
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• pp.15-24
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• 1986

In order to offer an basic data for the prevention of pesticide poisoning this study was carried out at Chun Song County, Kang Won Province for the period from 1983 to 1985. The major results are as follows: 1. The rates of those who read an explanation of pesticidesbefore scattering are 76.5% in 1983, 82.6% in 1984, 85.8 % in 1985 but among these people the rates of those who practice as explanation are 78.2%, 72.2%, 41.4% every year. 2. More than 50% of those who scatter pesticides feel pesticide poisoning. 3. The difference in average time of pesticide scattering and pesticide poisoning reveals statistical significance (P < 0.05). 4. Among those who feel pesticide poisoning, 85.5% in 1984, 87.3% in 1985 are due to insecticides.

• YAKHAK HOEJI
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• v.30 no.6
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• pp.348-351
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• 1986

New synthetic method for methyl-7-iodoheptanoate was studied. Methyl-7-iodoheptanoate is important compound in the synthesis codlemone, the sex pheromone of codling moth which doing harm to apple tree significantly, and this compound also be used essentially in the synthesis of prostaglandin derivatives. In previous the methyl-7-iodoheptanoate has been prepared from-7-chloroheptanoic acid as a starting material with disadvantage, since the 7-chloroheptanoic acid is expensive and the process is much complicate. In this paper the method to preparing methyl-7-iodoheptanoate was developed economically by using dihydropyran as a starting material in the course of 5 steps. Hence, methyl-7-iodoheptanoate which can be synthesized by new method studied onthis paper should be very useful compound for preparing codlemone or its acetate which will be used to developing pollution-free insecticides, and for preparing prostaglandin derivatives with advantage.