• Proceedings of the Korean Society of Sericultural Science Conference
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• 2002.10a
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• pp.146-146
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• 2002

No Abstract, See Full Text

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.95-99
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• 2004

Synthetic oligodeoxynucleotides (ODNs) containing unmethylated CpG dinucleotides in particular base contexts are known to induce immunity in vertebrate cells. In insect, however, it was recent to find out that ODNs induces insect immunity as other immune inducer such as lipopolysaccharide. However, the finding was solely based on one lepidopteran insect, Bombyx mori, and the expression of insect immunity was neither dependent on numbers of CpG repeats nor methylation of CpG repeats within ODNs. Instead, foreignness of DNA has been suggested to be a key factor governing induction of antibacterial peptide. In this study, we expanded our previous understanding to the potentiality of ODNs as an immune inducer for antifungal peptide in Galleria mellonella and B. mori. To do this, a defensin-type antifungal peptide gene, reported from G. mellonella was cloned and partially sequenced from G. mellonella and B. mori successfully and utilized as a probe in the Northern blot analysis. We found out that ODNs also work as an immune inducer for antifungal peptide in the fat body and midgut of G. mellonella and B. mori larvae. Also, induction pattern of antifungal peptide was irrelevant to the numbers of CpG repeats within ODNs as previously reported on the induction pattern of antibacterial peptides.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.487-494
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• 2017

Spinosad and spinetoram are widely used insecticides for the control of lepidopteran larvae, leaf miners, and thrips; however, they might also have low toxicity toward beneficial insects like bees. Because these pesticides are easily photolyzed by ultraviolet radiation, the QuEChERS method, with its simple pretreatment procedure, is often used for analyzing residues of spinosad and spinetoram. The present study performed a residue analysis using a modified QuEChERS method by pretreating with ammonium salt. The limit of detection (LOD) of the modified method was 0.05 mg/kg and the limit of quantification (LOQ) was 0.25 mg/kg. The coefficient of determination ($R^2$) for the calibration curve was 0.999. Also, we examined any change in the adhesion of spinosad and spinetoram on the plants depending on a spray volume. The adhesion was approximately 70% when the spray volume was increased from 60 L to 120 L per 10 a whereas the adhesion was approximately 37% when the spray volume was increased from 125 L to 250 L. This showed that the amount of adhesion decreased with the higher spray volume. The efficacy result of spinetoram was that over 90% of Frankliniella occidentalis was controlled with the application volume of 125 L per 10 a. Therefore, the result of this study indicates that control of insects is effective and sufficient with a spray volume of 125 L per 10 a in paprika cultivation facilities.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.217-223
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• 2014

The effects of insect capture were studied in a chestnut orchard using three different light traps (A, B, and C type) with various lamps. The mercury lamp trap captured 125 insect species, out of which 115 were chestnut pests. The B and C type light traps, comprising a Dulux-EL white lamp, were examined for their capturing ability. The type B trap attracted Coleopteran insects (83%), while type C captured Lepidopteran insects (73%). The mercury clarity lamp along with the type B light trap was most effective in attracting Curculio sikkimensis adults (mean, 9.8 adults), while the Dulux-EL lamp captured the highest number of Dichocrocis punctiferalis adults (mean, 10.2 adults) using the type C light trap. These results suggest that selection of the appropriate types of light traps and lamps based on the target pest species is critical in ensuring effective and eco-friendly control of the pest population.

• Korean journal of applied entomology
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• v.58 no.2
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• pp.101-109
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• 2019

An entomopathogenic bacterium, Xenorhabdus ehlersii KSY, is symbiotic to a nematode, Steinernema longicaudum, and exhibits high entomopathogenic virulence against lepidopteran insects. This study showed that the bacterial pathogenicity is induced by its inhibitory activity against eicosanoid biosynthesis of target insects, resulting in immunosuppression. To be applied for insect pest control, the bacteria should be infected to insect hemocoel. To deliver X. ehlersii to inset hemocoel, Bacillus thuringiensis (Bt) was mixed with the bacteria to breakdown the physical barrier (= midgut epithelium) from midgut lumen to hemocoel. The bacterial mixture significantly enhanced insecticidal activity of Bt only against larvae of Plutella xylostella and Maruca vitrata. For formulation, X. ehlersii cells were freeze-dried and mixed with sporulated Bt cells. The formulated bacterial mixture was applied to semi-field cultivating cabbage crop infested by P. xylostella. The bacterial mixture treatment showed over 95% control efficacy, while Bt alone gave 80% control efficacy. These results suggest that X. ehlersii can be applied to develop a novel insect control agent.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.517-522
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• 1998

The cry1 gene content of a collection of Bacillus thuringiensis strains, which include new isolates from Malaysia and Indonesia, was determined by a multiplex PCR using a set of eight oligonucleotide forward primers specific to cry1Aa, cry1Ab, cry1Ac, cry1Ba, cry1Ca, cry1Da, cry1Ea, and cry1Fa genes, and two reverse primers, one specific to cry1Ab and the other common to the remaining cry1 genes. Two-thirds of the 59 strains screened were cry1 positive and contained one to four different genes. The cry gene profiles correlated well with toxicities of the strains to lepidopteran insects. The method can be used for rapid screening of a large number of new isolates as the total DNA extracted by boiling cells from single colonies can be used directly in the PCR. However, it is not suitable for follow-up monitoring of specific commercial strains after application in the field as the PCR product profiles of these strains could not be differentiated from those of new isolates.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.159-165
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• 1997

We collected 3,237 plant samples, mainly leaves of various trees, from many provinces in Korea and a total of 1,925 Bacillus thuringiensis isolates were obtained and characterized. The isolates were characterized in terms of crystal morphology, PAGE pattern of the toxin proteins, plasmids pattern, biochemical characteristics, and bioassay. The microscopic observation showed that 49.1% of the isolates have bipyramidal shape crystals, 7.1% of spherical shape crystals, 1.4% of rhomboidal shape crystals, and others have small or amorphous inclusions. The insecticidal activities of the spore-crystal mixtures of isolates were tested against Plutella xylostella, Bombyx mori, Culex pipiens, and Agelastica coerulea. Bioassay showed that 51.3% of the isolates were shown to be active; lepidopteran-specific (44.8%), dipteran-specific(4.9%) and coleopteran-specific (1.6%). The remainder(48.8%) did not show any activity against the insects we tested. Interestingly though, some of these non-active isolates were shown to have bipyramidal crystals. By serotyping 22 isolates of our collection, we found that there are various kind of subspecies such as aizawai, amagiens, canadensis, darmstadiensis, galleriae, finitimus, kurstaki, morrisoni and neoleonensis, and three isolates have been classified into a new serotype, H49, and one of them, the type strain, named subsp. muju. From this study it was found that phylloplane is a good source for the isolation of Bacillius thuringiensis, and Bacillus thuringiensis is distributed widely in Korea.

• Animal Systematics, Evolution and Diversity
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• v.38 no.4
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• pp.214-221
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• 2022

Six species in five families of Lepidoptera were newly recorded from Korea. The adult specimens of these six species were obtained during the rearing caterpillars collected across Korea. Agonopterix omelkoi Lvovsky (Depresariidae) can be distinguished by the ochreous forewing with a dark brown slanted line, a dark brown triangular spot, and a blackish discal dot, and the whitish hindwing. Dichomeris ferruginosa Meyrick (Gelechiidae) can be diagnosed by the light brown forewing with two relatively large blackish dots and suffusion of dark brown along the dorsum and subtermen, and the grayish hindwing. Pseudohedya satoi Kawabe (Tortricidae) can be diagnosed by the dark ochreous forewing with several medially curved dark ochreous medial lines, and the large light grayish tornal marking, and the dark grayish hindwing. Rhodoneura hyphaema (West) (Thyrididae) can be diagnosed by the reddish forewing with a relatively thick postmedial band, and the reddish hindwing with a narrow dark reddish straight medial band. Comibaena subprocumbaria (Oberthür) (Geometridae) can be diagnosed by the greenish forewing with a whitish apical marking that bordered with a brownish or dark reddish line that connected to the termen, and the distal abdominal segments with whitish and dark reddish dots. Perixera absconditaria (Walker) (Geometridae) can be diagnosed by the light brownish forewing with a relatively thick, slanted, dentate brownish postmedial line, and the light brownish hindwing with a small white discal spot. We provide the diagnosis and figures of adults and larvae, and DNA barcoding data.

• Journal of Life Science
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• v.26 no.6
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• pp.737-748
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• 2016

By this time, insect antimicrobial peptides (AMPs) have been characterized more than 150 peptides since purification of cecropin in the hemolymph of pupae from Hyalophora cecropia in 1980. Therefore, it is considered that insects are good sources of AMP selection. Insect AMPs are small (low molecular weight) and cationic, and amphipathic with variable length, sequence, and structure. They perform a pivotal role on humoral immunity in the insect innate immune system against invading pathogens such as bacteria, fungi, parasites, and viruses. Most of the insect AMPs are induced rapidly in the fat bodies and other specific tissues of insects after septic injury or immune challenge. Then the AMPs subsequently released into the hemolymph to act against microorganisms. These peptides have a broad antimicrobial spectrum against various microbes including anticancer activities. Insect AMPs could be divided into four families based on their structures and sequences. That is the α-helical peptides, cysteine-rich peptides, proline-rich peptides, and glycine-rich peptides/proteins. For instance, cecropins, insect defensins, proline-rich peptides, and attacins are common insect AMPs, but gloverins and moricins have been identified only in lepidopteran species. This review focuses on AMPs from insects and discusses current knowledge and recent progress with potential applications of insect AMPs.

• International Journal of Industrial Entomology and Biomaterials
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• v.18 no.2
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• pp.113-120
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• 2009

Embryonic lethal abnormal visual (elav) is a lethal gene in Drosophila inducing the abnormal development and function of nervous system. We cloned a Bm-elav gene by bioinformatics and biological experiment, based on sequence of ELAV protein and dbEST of Bombyx mori. The full-length of Bm-elav cDNA is 1498 bp, contains a 906 bp open read frame (ORF) encoding a precursor of 301 amino acid residues with a calculated molecular weight of 34 kDa and pI of 8.99. Bm-ELAV protein precursor contains three RNA recognition motifs (RRM) in $24{\sim}91$, $110{\sim}177$ and $222{\sim}295$ bit amino acid residues respectively, and belongs to RNA-binding protein family. Bm-ELAV shared varying positives, ranging from 56% to 60% (Identities from 41% to 45%), with RRM from other species of Xenopus tropicalis, Apis mellifera, Tribolium castaneum, Branchiostoma belcheri and Drosophila. Gene localization indicated that Bm-elav is a single-copy gene, gene mapping within 12-chromosome from 7916.68 knt to 7918.16 knt region of nscaf2993. Spatiotemporal expressions pattern analysis revealed that Bm-elav expressed higher in most tested tissues and developmental stages in whole generation, such as silk gland, fat body, midgut, hemopoietic organ and ovary, but almost no expression in terminated diapause eggs. This suggested that the expression of Bm-elav in early developmental embryonic stages might induce abnormal development like in Drosophila. Cloning of the Bm-elav gene enables us to test its potential role in controlling pests by transferring the gene into field lepidopteran insects in the future.