• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.279-286
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• 2015

Cotesia plutellae bracovirus (CpBV) is a polydnavirus symbiotic to C. plutellae parasitizing young larvae of the diamondback moth, Plutella xylostella. Several CpBV genes play important roles in suppressing immune responses of the parasitized larvae. This study tested a hypothesis that the CpBV genes inducing host immunosuppression could be applied to develop a potent recombinant baculovirus. Based on a previous study, a recombinant baculovirus expressing CpBV-ELP1 (AcMNPV-ELP1) was selected and multiplied using larvae of the beet armyworm, Spodoptera exigua. The recombinant viruses were produced in a yield of $5{\times}10^{10}$ polyhedral inclusion body (PIB)/larva. The cultured AcMNPV-ELP1 exhibited a much higher pathogenicity against S. exigua larvae. However, its insecticidal activity was varied among larval instars of S. exigua, in which first and late instars were high susceptible. Spray of the recombinant baculovirus ($5{\times}10^6PIB/mL$) exhibited higher control efficacy (${\approx}$ 88%) against S. exigua larvae infesting cabbage than a chemical insecticide, tebufenozide, at 7 days after treatment. These results indicate that AcMNPV-ELP1 mass-cultured using host insect system is highly pathogenic and can be applied to develop a novel microbial control agent.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.317-322
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• 2015

This study was conducted to obtain basic data for deriving the appropriate application amount of insecticide for effective pest control. We have investigated the correlation among the application amount of insecticide, the adhesion amount of active ingredient and the pest control effect. The linear standard curve of acetamiprid was $R^2=0.9994$, and the scope of the recovery factor was between 71% and 93% with less than 6% of the coefficient of variation. During the test conducted in 2015, the application amount was reduced to 302 L/10a which was 70 L less than the previous year and the spraying pressure was reduced as well. After analyzing the adhesion amount of active ingredient, it was found that a correlation coefficient of adhesion amount of the active ingredients became lower from 82% to 69%, that indicated insecticide liquid was evenly distributed compared to 2014. Also more than 95% of control effect was displayed, thereby indicating that there is a close relation with the correlation coefficient of the adhesion amount of active ingredient. It also presented that the adhesion amount of active ingredient on the ground was 2.2 times more than that on the leaves of apple trees.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.669-684
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• 2013

This study was investigated to evaluate the effects of biodiversity and pest insect occurrence by soil surface management methods such as green manure crop, grass planting and clean-tilled crops on persimmon orchards. Green manure crop pests was investigated 7 species including Hypera postica, Laodephax striatellus, Megoura crassicauda, Aphis craccivora, Nephotettix cincticeps, Liriomyza sp., black spot and the most dangerous pest was H. postica but it did not damaged persimmon tree. Amount of pests and natural enemies dwelling soil covering plant was not difference between organic farming (hairy vetch planting) and conventional farming (natural weed). Homona magnanima occurred three times a year but it rarely damaged leaf of persimmon. Total adult moth catched by pheromone trap was 1,261 organic farm, 1,003 conventional farm and 621 clean-tilled farm. Grapholita molesta occurred four times a year but it also rarely damaged twig of persimmon. Number of collected invertebrate species and individuals on soil sample was follow as : 838 individuals of 22 species at organic farm, 421 individuals of 17 species at conventional farm and 381 individuals of 15 species at clean-tilled farm. The richness index was lined up by organic farm 3.12> conventional farm 2.65> clean-tilled farm 2.36.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.200-205
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• 2013

Mating disruption experiments were evaluated and compared in several pheromone traps and sex pheromone composition ratios at commercial chestnut garden for developing alternative control method of D. punctiferalis. The highest attractive was shown in Delta traps at the effective sex pheromone ratio of 75:25 (E10-16:A1:Z10-16:A1). Comparisons of domestic and imported pheromone constituents were not significant difference in 90:10 (E10-16:A1:Z10-16:A1). But, there was significant difference in sex pheromone ratio of 75:25. D. punctiferalis was caught the highest number in Gongju area for attractive test using pheromone trap. Attractive effects with dose of pheromone were showed the highest at 2.5 mg/lure and 1 mg/lure in Gongju area and Cheongyang area respectively. However, there was no significant difference among pheromone dose in Buyeo area. These data could be useful for eco-friendly managing of D. punctiferalis in the chestnut farm.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.213-219
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• 2013

This study focused on the promotion of the insecticidal activity of eco-friendly insecticidal materials against four major insect pest in the organic Chinese cabbage cultivation area. Among insecticidal materials mixture, BT+Matrine+Neem against leaf beetle larva, Phaedon brassicae, showed the highest 94.1% at 0.05% which is the lowest concentration of three treated concentrations. The insecticidal activity of Matrine, Neem, and BT alone (0.1%, w/v) or the mixtures (0.05%, w/v) against Cabbage worm larva, Artogeria rapae, was investigated by leaf disc spray method. The insecticidal efficacy of the mixtures of two or three eco-friendly materials was higher than the single treatment of each material with 94.3%, 100% and 100%. Control efficacy of 0.3% COY+0.05% (95.3%) against the green peach aphid, Myzus persicae was higher than that of 0.3% COY+0.05% Neem (90.2%) and lasted for more than 21 days after one time treatment. At 35 days after treatment, the effect of 0.05% BT+0.05% Matrine and 0.05% BT+0.05% Matrine+0.05% Neem treatments against diamondback moth showed very high insecticidal activity with more than 90% of control value. Therefore, BT, Neem, and Matrine where are properly treated could be effective eco-friendly materials for controlling major insect pests in an organic Chinese cabbage field.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.41-45
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• 1977

The systemic insecticides carbofuran $(Curaterr\; 3\%\; G)$ mephosfolan $(Cytrolane\; 2\%\; G)$ and disulfoton$(Disyston\; 5\%\; G)$ were evaluated in the field for conrol of some insects on soybeans when the insecticides were applied in seeding-pits at the rates of 4.6, 9.2 and 13.8 mg(a.i)/pit at the planting time. Control of the soybean aphid (Aphis glycines Matsumura) and the two-spotted spider mite (Tetranychus telarius(L.)) on soybeans was obtained for about 2 to 3 months, but their treatments were ineffective against the soybean moth (Grapholitha glycinivorella Matsumura). For the control of aphids and mites, disulfoton was better than carbofuran and mephosfolan. The insecticides slightly reduced the soybean stands, while the low-dose treatments of carbofuran slightly increased the stands. Carbofuran and mephosfolan caused severe phytotoxicity at the early stages, but disulfoton showed slight or negligible phytotoxicity. The phytotoxic symptoms in carbofuran and mephosfolan treatments were shelving the large number of brown or black-brown spots on the cotyledon and the first-leaves, and in addition to that showing necrosis along the leaf-margin. The symptoms in disulfoton treatments were slight withering along the leaf-margin of the first-leaves. In spite of good control of aphids and mites, there were no differences in soybean yield.

• Korean journal of applied entomology
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• v.49 no.1
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• pp.61-67
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• 2010

Effect of inoculation level on pathogenicity, development, and propagation of entomopathogenic nematode, Steinernema arenarium was investigated using the last instar of great wax moth, Galleria mellonella. Pathogenicity of S. arenarium was higher with increasing inoculation level representing 82% at the rate of 5 infective juveniles (IJs) while >98% at the rate of >10 IJs. The number of IJs penetrated into the host was 2.7, 5.0, 7.4, and 12.2 at the rate of 5, 10, 20, and 40 IJs, respectively while 24.3 at the rate of 80 IJs and 40.2 at the rate of 160 IJs. Inoculation level did not affect female adult size (4,616 to 6,444 ${\mu}m$) while affected male adult size (1,600 to 1,934 ${\mu}m$). The rate of stunted female adults was 70.2% at the inoculation level of 80 IJs and 63.7% at the inoculation level of 160 IJs. The number of progenies was 20,431, 26,696, 47,943, 50,516, 58,701, and 74,235 at the rate of 5, 10, 20, 40, 80, and 160 IJs, respectively. The body lengths of IJs were different depending on inoculation level ranging from 636 to 1,496 ${\mu}m$.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.165-169
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• 2017

Seasonal occurrence of persimmon bark borer moth, Euzophera batangensis, and attractiveness of its sex pheromone gland components and trap types were studied at sweet (non-astringent) persimmon orchards of two southern provinces of Gyeongsangnam-do and Jeollanam-do, Korea, from 2014 to 2016. E. batangensis occurred three times a year. Occurrences of the moths of the over-wintered, the $1^{st}$ and the $2^{nd}$ generations were early April to late May, early June to late July, and early August to mid October, respectively. The (Z9,E12)-tetradeca-9,12-dien-1-ol (Z9,E12-14OH) was more attractive than (Z)-tetradec-9-en-1-ol (Z9-14OH). The Z9,E12-14OH was equally attractive to the 9:1 binary mixture of Z9,E12-14OH and Z9-14OH to the male moths. The three trap types of funnel, white and red delta traps had no effect on the attractiveness of the components.

• Korean journal of applied entomology
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• v.36 no.4
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• pp.323-330
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• 1997

The apple leafminer, Phyllonorycrer ringoniella (Lepidoptera: Gracillariidae), is the most important pest on apple leaves and is not easy to be controlled with insecticides because of leafmining habit of its larvae. This study was undertaken to develop an artificial diet for mass rearing of the moth, and to look at their reproductive behavior. For developing an artificial diet the problem of diet contamination with microorganisms and how to supply artificial diet to first instar larvae have to be solved first. Artificial oviposition trial was successful with shadowy bottomside of various papers sprayed with apple leaf extracts. The highest activity of both calling and mating was observed within 30 min. after the onset of photophase and 3- to 4-day -old adults showed the highest mating rate. A ring-shaped sex pheromone gland was found at the intersegmental membrane between the 8th and 9th abdominal segments of the female. (E, 2)-4,lOtetradecadienyl acetate was identified as the major component from the femall gland extracts by the gas chromatography (GC) and GC-mass spectrometry. Additionally it was thought that (a-10-tetradecenyl acetate could be the second component of their sex pheromone.

• Korean journal of applied entomology
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• v.50 no.2
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• pp.107-113
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• 2011

Benzylideneacetone (BZA) is a compound derived from culture broth of an entomopathogenic bacterium, Xenorhabdus nematophila (Xn). Its immunosuppressive activity is caused by its inhibitory activity against eicosanoid biosynthesis. This BZA is being developed as an additive to enhance control efficacy of other commercial microbial insecticides. This study was focused on the enhancement of the immunosuppressive activity of BZA by generating its chemical derivatives toward decrease of its hydrophobicity. Two hydroxylated BZA and one sugar-conjugated BZA were chemically synthesized. All derivatives had the inhibitory activities of BZA against phospholipase $A_2$ ($PLA_2$) and phenoloxidase (PO) of the diamondback moth, Plutella xylostella, but BZA was the most potent. Mixtures of any BZA derivative with Bacillus thuringiensis (Bt) significantly increased pathogenicity of Bt. BZA also inhibited colony growth of four plant pathogenic fungi. However, BZA derivatives (especially the sugar-conjugated BZA) lost the antifungal activity. These results indicated that BZA and its derivatives inhibited catalytic activities of two immune-associated enzymes ($PLA_2$ and PO) of P. xylostella and enhanced Bt pathogenicity. We suggest its use to control plant pathogenic fungi.