• Korean journal of applied entomology
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• v.31 no.4
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• pp.452-460
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• 1992

To establish the economical and reliable routine bioassay system for developing new insecticidal compounds, effects of leaf-dipping time, application methods, insect species and their developmental stages on susceptibilities of insects to insecticides were studied. The stable insecticidal activity appeared at the dipping time for 30-60 seconds in leaf-dipping method, and the most effective application methods were leaf-dipping method for apterous green peach aphid adults, and third instars of diamond-back moth and tobacco cutworm, whereas seedling+insect spray method for adults or third instars of brown planthoppers. For two-spotted spider mite, leaf-dipping or intact plant spray method was favorable. In the bioassay for chitin synthesis inhibitors, the inoculation of third instars of brown planthopper, diamond-back moth, tobacco cutworm and green peach aphid, and larvae of two-spotted spider mite to the young host plants treated by spray method were adequate bioassay methods.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.173-177
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• 1986

This study was carried out to see what makes the 'dark grey cutworm', Agrotis tokionis Butler, inflict less damage in P.E. film-mulched tobacco fields than in nonmulched ones. In field plot experiment, the damage ratio of tobacco seed lings in mulched plots(m) was reduced by 63% compared with that in non mulched ones(n). The altered environments did not affect the cutworm in mortality, which was confirmed by recovery ratio, location of larvae in soil, and developmental age. But the m/n value and damage ratio in plots of different mulching methods strongly suggest that the P.E. film itself prevent larvae from cutting the plants. Larval mortality was rapidly increased between the end of July and the end of August.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.307-316
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• 1996

A persistent major haemolyruph protein (MHP) was confirmed, and its ontogeny and physicochemical charadedstics were investigated in Helicoverpa assulta. The MHP existed continually during larval-pupal-adult development, and its ontogeny was similar to that of total haemolymph protein concentration during development. Its content increased with larval growth, and kept to high level during pupal-adult development except for temporary decrease at the early pupal and adult stages. The MHP was purified by ammonium sulfate precipitation, gel filtration and ion exchange chromatography. The purified MHP was determined to be hexamer glycolipoprotein (pI 5.9, M.W. 414kDa) consisted of single type subunit (69kDa). Amino acid analysis suggested that the MHP contained a relatively high content of aromatic amino acids (18.27 mole % of tryptophan, 7.47 mole % of tyrosine and 6.51 mole % of phenylalanine) compared to storage proteins from other insects. Immunodiffusion test and electrophoretic analysis of the organ proteins (gut, fat body, and Malphigian tubule) suggested that the major haemolymph protein was present in the fat body.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.509-517
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• 2009

Bacillus thuringiensis subsp. aizawai CAB109 isolated in Korea is known active against Spodoptera sp.. Especially, B. thuringiensis aizawai CAB109 isolates showed 100% mortality against Spodoptera litura and Spodoptera exigua. To screen highly active B. thuringiensis, the pathogenicity of B. thuringiensis CAB109 was compared with that of commercialized B. thuringiensis products. $LC_{50}$ values of CAB109, product TB-WP and product SC strains of B. thuringiensis were $1.3{\times}10^5$, $2.3{\times}10^6$ and $5.2{\times}10^5\;cfu/ml$ against the 2nd larva of S. litura and $1.8{\times}10^4$, $1.3{\times}10^6$ and $1.5{\times}10^6\;cfu/ml$ against the 2nd larva S. exigua, respectively. To determine new gene's existence and absence, the plasmid DNA was extracted, and compared to that of B.t. aizawai HD-133. Both B. thuringiensis were not like plasmid DNA pattern. PCR technique was used to predict both plasmid DNA's cry gene. PCR products analysis showed that B.t. CAB109 harbor Cry1Aa, Cry1Ab, Cry1C and Cry1D and B.t. HD-133 has Cry1Aa and Cry1Ab, respectively.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.18-28
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• 1991

The optimal pH of the extraction buffer was 7.5 considiering AChE stability and its buffer capacity when AChE was isolated and extracted from the housefly(Musca domesitca L.)and three other insect species with 0.01 M sodium phosphate buffer. Also, the optimal pH of the reaction buffer was 7.5 considering enzyme activity and its buffer capacity when AChE activity was measured with the substrate in 0.1 M sodium phosphate buffer. The Potter Elvehjem type homogenizer with Teflon pestle was used to homgenize the tissues. When preparing a AChE suspension by centrifuging the homogenate, 700 g supernatant of adult head for the housefly, 700 g supernatnat of 5th instar nymphal whole body for the brown planthopper, lipid-eliminated 10,000 g supernatant of 5th instar larval whole body for the diamondback moth, and 700 g supernatant of 4th instar larval head for the tobacco cutworm were considered satisfactory as enzyme sources in view of mass preparation, extraction efficiency and stability of enzyme activity during evaluation. When AChE suspensions of 4 insect species were stored at $-18^{\circ}C$, more than 90% of activity was maintained up to 3 weeks. Km values of AChEs of the housefly, the brown planthopper, and the diamondback moth were 0.042, 0.037 and 0.043 mM, respectively and AChE-specific substrate inhibition was observed at high concentration. Km value of the tobacco cutworm ChE was 1.15 mM and BuChE characteristics was observed, though further study is needed. The optimal substrate concentration for the AChE inhibition tests was 0.5 mM for the housfly, the brown planthopper, and the diamondback moth and 12 mM for the tobacco cutworm.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.45-51
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• 2013

Tropical plants of mango(Mangefera indica), dragon fruit(Hylocereus undatus), and atemoya(Annona cherimola ${\times}$ A. squamosa) are cultivated in Jeju, Korea. A pest survey on those tropical fruits was conducted from 2008 to 2011. Major pests of Mango were thrips, aphid, mealybug, and lepidoptera species. Thrips palmi and Scirtothrips dorsalis were the most important pests in mango fields. T. palmi mainly injured the leaf but S. dorsalis injured the leaf and fruit. Lepidoptera mango pests injured leaves but some larva of Adoxophyes honmai injured fruit surface around the stem. Aphid pests, Aphis gossypii and Myzus persicae, injured the shoots and Pseudococcus kraunhiae occurred on the stem and fruit. Ant species, A. gossypii, and S. litura, were important pests on dragon fruit. Ants and aphid occurred and injured the stem, flower, and fruit. Spodoptera litura larva severely injured the stem. Among the atemoya pests, S. litura and Homona magnanima caused severe damage.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.30-42
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• 2011

Moths were collected to survey turfgrass pest and to compare species diversity from Jinju Country Club in Jinju, Gyeongsangnamdo, Korea, every 10 days using 200W mercury light trap from middle May to late October in 2008. As the results, only 23 individuals of Pseudaletia separata, Spodoptera depravata, Spodoptera litura, Agrotis segetum, and Agrotis ipsilon were collected as turf grass insect pests. However, 2028 individuals of 388 species in 22 families were collected in total. Dominant species was Culcula panterinaria, Fentonia ocypete, Hypsopygia regina, Culcula panterinaria, Flavocrambus striatellus, and Diarsia camescens in May, June, July, August, September and October, respectively. Species diversity was not different between two surveyed sites, but different among surveyed time. Species richness was more higher in hole 11 (Hole was surrounded by natural forest and located near pond) than hole 15 (Hole was located at the top part of mountain). Dominance index of moth was increased from October compared with diverse index and richness index were decreased from October. A large number of species and individuals were recorded in Noctuidae (502 individuals in 131 species), Geometridae (491 individuals in 84 species), Pyralidae (386 individuals in 73 species), and Notodontidae (277 individuals in 25 species). These four families were 80.9% out of all the collected species.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.05a
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• pp.139-139
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• 2001

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.11a
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• pp.156-156
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• 2001

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2000.10a
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• pp.70-70
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• 2000