• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.18-25
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• 2001

Ethanol extracts from 46 vegetables were tested their insecticidal activities toward five agricultural insect pests and four stored-product insect pests. The efficacy varied with both agricultural insects/stored-product insects and vegetable species used. Potent insecticidal activities, at the concentration of 5,000 ppm, were produced from extracts of Nelumbo nucifera and Ulva lactuca against Myzus persicae, Zea ways and Z. mays (leaf) against Nilaparvata lugens, Citrullus vulgaris (seed) and U. lactuca against Plutella xylostella, N. nucifera, Z. mays, and Z. mays (leaf) against Spodoptera litura, and C. vulgaris (seed), Daucus carota, Helianthus annuus (leaf), H. annuus (flower), Lactuca sativa, and Zingiber officinale against Tetranychus urticae. Potent insecticidal activities at the concentration of 2,500 ppm were exhibited from the extracts of N. nucifera and U. lactuca against M. persicae, Z. mays against N. lugens, C. vulgaris (seed) and U. lactuca against xylostella, N. nucifera and Z. mays against S. litura, and C. vulgaris (seed), H. annuus (flower), and L. santiva against T. urticae. Against four stored-product insect pests at 50 ppm, extracts of C. vulgaris (seed) and Cucurbita moschatla (seed) against Sitophilus oryzae and C. vulgaris (seed), H. annuus (seed), and Z. officinale against Plodia interpunctellfa revealed potent insecticidal activities over 80% mortality. In tests with Callosobruchus chininsis and Lasioderma serricorne, extracts of all vegetables tested exhibited meager and no activity.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.849-857
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• 2016

In the growth of the Rubus coreanus Miquel fruits, the unripened (10 days) and ripened (25 days) fruits after flowering were harvested. The chemical characteristics of different maturational stages of the unripened and ripened fruits were investigated. Total amount of phenolic compounds was 4.00-7.56% in the unripened fruits and 3.78-5.57% in the ripened fruits, respectively. Furthermore, total amounts of organic acids such as malic, citric, succinic, and oxalic acids were 16.40 mg/100 g in the unripened fruits and 28.82 mg/100 g in the ripened fruits, respectively. In organic acids of the unripened and the ripened fruits, citric acid (8.76-15.47 mg/100 g) was the highest amount among other organic acids. Soluble sugars were significantly increased from 11.07 to 21.54% in the unripened and ripened fruits. Therefore, ripened fruits had the high levels of phenolic compounds, organic acids and soluble sugars. For the biological studies of R. coreanus, methanol extracts of R. coreanus leaves, fruits, and stems were evaluated for their insecticidal activities against Myzus persicae (Hemiptera: Aphididae), Plutella xylostella (Lepioptera: Plutellidae) and Spodoptera litura (Lepioptera: Noctuidae) by leaf dipping method. From these results, the extract of R. coreanus leaves revealed potent insecticidal activity against P. xylostella. However, the methanol extracts of R. coreanus fruits and stems had no any insecticidal activity against M. persicae, P. xylostella and S. litura. The R. coreanus leaves have promising potential as new insecticidal agent against P. xylostella.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.27-32
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• 2001

Methanol extracts from 43 materials of 17 fruit trees were tested for their insecticidal activities toward five agricultural and four stored-product anthropod pests. Efficacy varied with insect species, plant species, and tissue sampled. At a concentration of 2,500 ppm, strong activity was observed with extracts of Chaenomeles sinensis and Punica granatum seeds against Myzus persicae adult females, Vitis vinifera seeds against Nilaparvata lugens adults, Citrus junos, Citrus paradisi, Cucumis melo Linne var. reticulatus, Diospyros kaki, Malus pumila var. dulcissima, Prunug persica, and V. vinifera seeds against Plutella xylostella, Citrus sinensis seeds against Spedoptera litura larvae, and Ch. sinensis and V. vinifera against Tetranychus urticae adults. Against four stored-product insect pests at 50 ppm, seed extracts of Ch. sinensis and V. vinifera against Sitophilus oryzae adults, and Ch. sinensis, C. junos, D. kaki, and V. vinifera against Callosobruchus chinensis adults gave over 80% mortality. Extracts of all samples exhibited little and no activity against Lasioderma serricorne adults and Plodia interpunctella larvae.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.145-152
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• 2003

Field application of the entomopathogenic nematode, Steinernema carpncapsae, is limited by its susceptibility to UV irradiation and desiccation especially at leaf spray control. This study was conducted to develop the control technique using alginate biocapsulation of the nematodes against the beet armyworm, Spodoprera exigua and the tobacco cutworm, Sp. litura that are normally infesting hosts above ground level. The alginate capsules including infective juveniles gave significant feeding toxicities to the larvae of the two lepidopteran species. The lethality followed a typical sigmoid dose-mortality pattern with increase of the nematode densities embedded in the capsules. Moisture content in the capsule was critical to the survival of the infective juveniles. More than 80% nematodes could survive above 10% moisture content remained in the capsule. Remaining moisture content within the capsule was dependent on relative humidity, ambient temperature, and capsule size, but not on citric acid reaction time during capsule formation. More than 80% of infective juveniles in the alginate capsules could survive in distilled water at 15$^{\circ}C$ for 60 days. When these nematode capsules containing welsh onion extract as another phagostimulant were applied on the 3rd instar larvae of Sp. exigua infesting peanut plants, they resulted in about 90% control efficacy. These results indicate that the alginate capsulation can be used for leaf-spray agent of the entomopathogenic nematodes as well as for improved storage purpose.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.300-306
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• 1993

The CryIIA gene encoding the insecticidal crystal protein of Bacillus thuringiens!s subsp. kurstalri HD-l has been cloned in Escherichia col!, and its nucleotide sequences were determined completely. 5kb Hindlli fragment harboring CryIIA gene was screened in the large ca. 225kb plasmid DNA by southern blot. HindlIT digested 5kb fragment was ligated into pUC19 and transformed in E. coli. The 4kb BamHI-HindlIT fragment containing the CryIIA gene was subcloned and named pSKIIA. DNA sequence analysis demonstrates that pSKIIA is the gene of an operon which is comprised of Lhree open reading frames (designated orn, orf2 and or£3). The CrylIA gene is composed of 3,952bp-long BamHI-Hindill DNA restriction fragment. The orf3 code for a polypeptide of 633 amino acid residues. The protoxin protein has a predicted molecular weight of 70,780. The E. coli derived protoxin gene product is biologICally active against three species of Lepidopteran (Plu.lelia maculipennis, He/iolhis assulta, Spodoptera litura) and a species of Dip Leran( Culex pipines) larvae in bioassay.

• Applied Biological Chemistry
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• v.45 no.1
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• pp.37-41
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• 2002

Seven organophosphorus compounds and three carbamates of some monoterpenoids were synthesized and tested for insecticidal activity to five insects, brown plant happer (BPH, Nilaparvata lugens), green peach aphid (GPA, Myzus persicae), diamond bark moth (DBM, Plutella xylostella), tobacco cut worm (TCW, Spodoptera litura), and two spotted spider mite (TSSM, Tetranychus urticae). With the administration of 500 mg/l concentration thiophosphates of carveol and geraniol showed motality of from 95% to 100% to BPH and DBM. On the other hand, phosphates of menthol, thymol, and borneol had also good to moderate activity to BPH and TSSM insects at the same concentration.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.75-76
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• 2024

The ovicidal effect of plant extract mixture (5%cinnamon extract + 10% citronella oil + 30% citrus oil + 10% derris extract + 20% neem extract + 25% penetrating surfactant) against several major insect pests was tested using the spraying method. In the case of stink bugs, eggs tended to die during hatching. When treated with a plant extract mixture (500-times solution), mortality for Halyomorpha halys, Riptortus clavatus, Eurydema dominulus, Trialeurodes vaprarorium, Bemisia tabaci, Spodoptera exigua, and Agrotis ipsilon reached as high as 100%. Therefore, it is believed that industrialization will be feasible in the future.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.1
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• pp.39-48
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• 1996

A storage protein(SP-2) was confirmed in haemolymph during larval-pupal-adult development of tobacco burdworm(Helicoverpa assulta Guenee), and its biochemical characteristics were investigated. The titer of SP-2 showed a peak at mature larva, decreased gradually through the late pupal stage, and became undetectable at adult period. As the results from electrophoretic mnysis, SP-2 was confirmed to be glycolipoprotein(M.W. 332kDa) relatively stable to heat( $\leq$ 68$^{\circ}C$ ). This storage protein was determined to be a tetramer composed of a single subunit with MW of 83kDa, and the isoelectric point was 5.7. The amino acid composition of the SP-2 was characterized. It has relatively high content of methionine and histidine, whereas the contents of tyrosine and phenylalanine were relatively low.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.71-79
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• 1998

Haemolyph carboxylesterases induced in diapausing pupae of Helicoverpa assulta Guenee were investigated. Increase in the activity of the electrophoresed isozyme bands were observed during the diapausing pupae. The isozymatic composition exhibited remarkable alterations represented as disappearance and induction of some isozyme bandsp which were identified as carboxylesterase (CE) on the basis of their specificities to inhibitors. Much higher activity of the induced CE was shown in reaction with $\beta$-naphthyl acetate ($\beta$-Na) than $\alpha$-naphthyl butyrate ($\alpha$-Nb), representing the high regioselectivity to $\beta$-naphthyl group. Optimal temperature for the enzyme activity was different to the substrates used 37$^{\circ}C$ in $\beta$-Na and 4$0^{\circ}C$ in $\alpha$-Nb, respectively. However, the optimal pH for the enzyme activity was the same as 7.5 regardless of the substrates used, and relatively high thermostability of the CE was demonstrated by showing the denaturation at high temperature (50~55$^{\circ}C$).

• Journal of the Korean Society of Tobacco Science
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• v.21 no.2
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• pp.171-181
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• 1999

We examined the ultrastructure of eupyrene and apyrene spermatogenesis in the testis of Helicoverpa assulta (Lepidoptera: Noctuidae). The spermatogenesis was progressed near the fringe adjacent to the follicular layer of the testicular follicle, surrounding the apical cell concentrically. Eupyrene and apyrene were firstly distinguished at the telophase stage of the primary spermatocyte. Chromatin was evenly scattered in eupyrene nuclei, whereas it was lumped near the nuclear envelope in apyrene spermatogenesis. Then, the nucleus of eupyrene was transformed into two daughter nuclei by meiosis, while the nucleus of apyrene was divided into many micronuclei by irregular meiosis. After the meiosis was completed, a number of mitochondria in the cytoplasm of the early spermatids of the eupyrene and the apyrene were fused into one nebenkern. Also, as axial filament was formed due to the elongation of the spermatid, the nebenkern became splitted into mitochondrial derivatives. An acrosome precursor was present only in the eupyrene, attached to nuclear envelope.