• Korean journal of applied entomology
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• v.36 no.4
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• pp.351-356
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• 1997

Biological control of forest insect pests, Agelastica coeruleci, Meganola n~elancholia,a nd Glyphodes perspectalis, turfgrass insect pest, Blitoperfhu orientr~lis,v egetable insect pests, Plutella xylostella and Agrotis segetun~ with entomopathogenic fungus, Beciuveria hassinna GY 1 - 17 isolated from rice paddy of Yangsan in the southern part of Korea were investigated. Mortalities of A. coeruleu and P. ~ylo.~rellluar vae were 100% at the rate of 7.0 and 2.0 x 107conidia/ml after 7 and 5 days and those of M. melancholia were 66.7 - 100% at the rate of 0.03875-3.1 X 107conidia/ml. However, G. perspectulis was not affected at the rate of 2.0 x lo7 to X I04conidia/ml. And mortalites of B. orientcilis and A. segetum larvae were 46.7% at 3.7 x 107conidia/ml and 63.3% at 2.5 X 107conidia/ml.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.16-21
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• 2004

A series of experiments was conducted to determine the toxicities of thiodicarb on the six lepidopterous pests (Pseudaletia separata, Plutella xylostella, Palpita indica, Spodoptera exigua, Helicoverpa assulta, Spodoptera litura) and to elucidate factors insecticidal effects mechanism of thiodicarb. Thiodicarb was very effective against six lepidopterous young larvae, but less effective to the old larvae and it acted slowly. Thiodicarb inhibited acetylcholinesterase and glutathione S-transferase activities, but not inhibit esterase activity.

• Agrochemical news magazine
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• v.16 no.3 s.126
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• pp.27-29
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• 1995

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.162-167
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• 2004

In recent years, the diamondback moth (DBM), Plutella xylostella has become one of the most important pests for cruciferous plants in the world. A new type of the thiophosphoryl pyrazole insecticide, called KH502. Its outstanding insecticidal activity could be effective alternative against DBM. We investigated, using the comparative molecular field analysis (CoMPA) method, The structure-activity relationship of various thiophosphorylpyrazole derivatives and structure requirement for insecticidal activity. We found, the key substructures in pyrazole derivatives, the trifluoro-methyl group and the thiophosphoryl group. Both play an important role in insecticidal activity with the binding site. The three dimensional Quantitative Structure Activity Relationship (QSAR) analysis could provide useful information for the structural requirements of pyrazole insecticide as an insecticidal and the design of a new insecticide.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.27-33
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• 2000

N-Dimethoxyphosphinothionyl carbofuran, PSC, has a high insecticidal activity and low mammalian toxicity. Ten N-phosphinothionyl carbofuran derivatives were synthesized and their insecticidal activities were determined against brown plant hopper (Nilaparvata lugens), green peach aphid (Myzus persicae), diamondback moth (Plutella xylostella), and two-spotted spider mite (Tetranychus urticae). Green peach aphid, diamondback mea and brown plant hopper were controlled over 90% by application of 125 ppm, 125 ppm, and 63 ppm, respectively, of carbosulfan. Two hundred and fifty ppm of newly synthesized compounds could control most of brown plant hopper and diamondback moth. Especially, insecticidal activities of compound 10 against brown plant hopper, diamondback moth, and green peach aphid were similar to those of carbosulfan. Our results show that the newly synthesized derivatives of NV-phosphinothionyl carbofuran have a similar insecticidal activity to carbosulfan.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.315-324
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• 2009

For the environmental friendly management of diamondback moth, Plutella xylostella (L.), Bacillus thuringiensis subsp. kurstaki ($30{\times}10^8\;cfu/mg$) and neem oil (0.5% azadirachtin) were used as green control agencies with mixed and alternative treatments on the chinese cabbage. When Bacillus thuringiensis subsp. kurstaki was applied to 1st and 2nd larva of P. xylostella with recommended concentration, their mortalities were reached to 100% by 2 days after treatment. In case of azadirachtin, its effect of mortality was continued for 7 days, and reached to 100% mortality. $LC_{50}$ values of Bacillus thuringiensis subsp. kurstaki and azadirachtin against 1st, 2nd, 3rd and 4th larva of P. xylostella were $2.8{\times}10^4$, $3.1{\times}10^4$, $3.4{\times}10^4$ and $1.5{\times}10^5\;cfu/ml$, and 2.7, 3.9, 4.7 and 7.1 ppm, respectively. The number of laid eggs of P. xylostella was reduced to 57.5 at 25 ppm of azadirachtin compared with control treatment. The hatch ratio was not significantly different with Bacillus thuringiensis subsp. kurstaki treatment in comparison with control treatment. However, when azadirachtin was applied, their hatch ratio were reduced to 25.8 and 45.4% at 25 and 50 ppm, respectively. On the other hand, emergence rate of eggs was not different with Bacillus thuringiensis subsp. kurstaki treatment, but 45.4% was shown in azadirachtin treatment with 50 ppm in comparison with control. When the mixture with Bacillus thuringiensis subsp. kurstaki and azadirachtin was applied to adults of P. xylostella, their mortality was higher than Bacillus thuringiensis subsp. kurstaki treatment only. These results are supposed that the mixture of Bacillus thuringiensis subsp. kurstaki and azadirachtin might be used as green control agents for reducing the demage of diamondback moth in the Chinse cabbage.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.355-365
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• 2014

It has been unclear whether the diamondback moth, Plutella xylostella can overwinter in Korean field conditions. This study determined overwintering conditions of P. xylostella by conducting field exposure tests based on its cold tolerance and monitoring overwintering populations by direct examination of overwintering larval habitats and capturing adults with sex pheromone traps. In addition, the overwintering populations were analyzed using polymorphic genetic markers to trace their sources. When all immature stages of P. xylostella were exposed to $-5^{\circ}C$, which was the temperature much above their supercooling points, they significantly suffered with direct cold injuries, where larval stage was most tolerant to the cold injury. However, the exposure to $5^{\circ}C$ for a long period (4 weeks) did not give any significant cold injury to nonfeeding stages, while this treatment gave lethality to larval stage without diet. When all developmental stages of P. xylostella were exposed to open field conditions during winter, they exhibited significant decreases of survival rates. However, some protected and indoor conditions reduced the cold injuries and the diet provision significantly increased larval survival rates. Adult monitoring with sex pheromone during winter period indicated that the first captures were observed at similar periods at different locations (${\approx}260$ Km apart). The overwintering adults were captured until early April. Genetic variation of these overwintering populations was analyzed with polymorphic molecular markers, indicating significant genetic divergences among the overwintering populations. This study indicates that P. xylostella can overwinter in southern Korean fields or some protected greenhouses with host plants.

• Journal of the Korean Chemical Society
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• v.34 no.2
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• pp.179-183
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• 1990

New synthesis and electroanthennogram (EAG) responses of the pheromones of the diamond back moth Plutella xylostella L. are described. Lithium dianion of propargyl alcohol was alkylated with 1-bromononane to give 2-dodecyn-1-ol, which was converted to 11-dodecyn-1-ol by acetylene-zipper reaction. Dianion of 11-dodecyn-1-ol was alkylated with 1-bromobutane to provide 11-hexadecyn-1-ol, which was in turn reduced over Pd/BaSO4 to afford (Z)-11-hexadecen-1-ol (3). (Z)-11-Hexadecen-1-ol was oxidized and acetylated to (Z)-11-hexadecen-1-al (1) and (Z)-11-hexadecen-1-yl acetate (2), respectively. The electroantennogram (EAG) responses of the diamond back moth to the pheromone compouds thus synthesized were measured.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.194-200
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• 1990

The diamondback moth (Plutella xylostella L.) was selected over 24 generations with fenvalerate. The resulting resistant strain was tested to study development of insecticide resistance and cross resistance to some insecticides in the laboratory. Insecticide resistance of diamondback moth at the 24th generation devleoped 66.2 fold compared to the parent strain for fenvalerate. The fenvalerate selected strain exhibited 145 fold, a high level of cross resistance to deltamethrin, and also showed 17.4-45.0 fold cross resistance to alphamethrin, cypermethrin, fenvalerate, permethrin, and tetramethrin in the pyrethroid insecticides. The fenvalerate selected strain showed 2.5-4.3 fold, low cross resistance to diazinon, dichlorvos, EPN, BPMC, cabaryl, and methomyl. However, it did not show cross resistance to acephate, fenitrothion, phenthoate, and carbofuran.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.385-392
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• 2009

Two entomopathogenic bacteria, Xenorhabdus nematophila and Photorhabdus temperata subsp. temperata, are known to be potent against the diamondback moth, Plutella xylostella, when the bacteria are injected into the hemocoel. This study investigated any pathogenic effect of their culture broth on P. xylostella by oral administration. Only culture broth of both bacterial species did not give enough pathogenic effects by the oral administration. However, when the culture broth was orally treated together with Bacillus thuringiensis (Bt), both cell-free culture broth significantly enhanced Bt pathogenicity against the 3rd instar larvae of P. xylostella. The culture broth was then fractionated into hexane, ethyl acetate, and aqueous extracts. Most synergistic effect on Bt pathogenicity was found in ethyl acetate extracts of both bacterial species. Thin layer chromatography of these extracts clearly showed that ethyl acetate extracts of both bacterial culture broths possessed metabolites that were different to those of hexane and aqueous extracts. These results suggest that the both entomopathogenic bacteria produce and secrete different factors to give significant synergistic effect on Bt pathogenicity.