• Korean journal of applied entomology
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• v.54 no.4
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• pp.359-367
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• 2015

Physiological plasticity of insects can be closely related with their epigenetic change. This hypothesis was tested using a polyphagous lepidopteran insect, Spodoptera exigua, by assessing the effects of different diets on development and DNA methylation. Three different diets (Welsh onion (WO), Chinese cabbage (CC), artificial diet (AD)) were assessed by feeding a cohort of larvae from neonate to last instar. There were significant differences in larval developmental rate, pupal weight and adult emergence according to diet treatments. AD-fed larvae exhibited the fastest developmental rate along with the highest pupal weight and adult emergence. Among natural hosts, WO was more favorable for development of S. exigua than CC. Total hemolymph proteins and sugars in the last instar larvae were varied among different diets. Gene expression of an insulin-like peptide (SeILP1) presumably associated with development was also varied among diets. Cytosine methylation of genomic DNA was assessed using a monoclonal antibody. Genomic DNA of S. exigua larvae was methylated. DNA methylation was apparently varied among different diet-fed larvae. The facts that a cohort of S. exigua was differentiated in developmental rate and cytosine methylation by different diets suggest that epigenetic factor(s) may play a crucial role in the physiological plasticity.

• Korean journal of applied entomology
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• v.28 no.2
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• pp.88-92
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• 1989

The Oriental tobacco budworm, Heliothis assulta (Guenee), larvae usually feed on the hot-pepper fruits and young tobacco leaves or buds in Korea. This experiment was conducted t(} compare their attraction to their host plants including fruits of the sweet-pepper and solanum uk kwang, besides the other two mentioned above. First instar larvae were most attracted to the hot-pepper fruits. Flowers or leaves of the hot pepper plants were not attractive either. When the hot-pepper fruits were compared for attractancy, based on developmental stages, relatively mature fruits, just before ripening, were the most attractive. Their extract with or without 10% ethanol also gave similar result to 1st instar larvae or 2~4 instar larvae, suggesting a possibility that there is an attractant(s) in the hot-pepper fruits.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.2
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• pp.67-72
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• 2015

In this study, growth characteristics of insects for mass production was investigated. For Hermetia illucens, the biomass was increased by the supply of the mixture of FWDF with hop cake and typical feed at the early growth stage, however, no difference was shown between 100% of FWDF and the mixture at the late stage. The growth of Housefly larvae was retarded with the 100% of FWDF, resulting in abnormal paputation, hence the amount of FWDF shoud be lowered to 20% to 30% for the efficient growth. Super mealworm larvae was found to grow with little influence by the kind of feed, and none of them was died or inhibited by the supply of FWDF as a feeding source.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.203-208
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• 2011

This study was conducted to evaluate Geometridae (Lepidoptera) species as pests and the damage they cause in citrus orchards in Jeju, Korea. Seven geometridae species occurred in citrus orchards: Ascotis selenaria, Ectropis excellens, Menophra senilis, Biston panterinaria, Ourapteryx nivea, Odontopera arida and Hypomecis punctinalis. Among them, A. selenaria was most abundant, followed by E. excellens and M. senilis. Most Geometridae larvae fed on citrus leaves, but A. selenaria larvae ate fruits and leaves. Fruit damage of Citrus unshiu appeared as gnawed scars caused by young larvae feeding on fruit surface. Fruit damage on Shiranui fruits appeared as a wide hole or deep scars caused by feeding by mature larvae (6th instar). Citrus leaves damage due to Geometridae larvae was high during May to June. Fruit damage started in late June as the spring-shoots of citrus hardened and increased sharply in late July. In the field experiment, fruit damage in the late season reached 4.2% in both 2008 and 2009 and reached 5.2% in 2010. In citrus orchards, A. selenaria larvae started to appear in mid-May and their populations peaked in mid June, late July, and early to mid-September. Adult males of A. selenaria had a maximum peak in mid-May, and two other peaks in early to late July and late August to early September. A. selenaria male adults were collected in a pheromone traps constantly throughout Jeju Island.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.139-143
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• 2006

Imago's flight activities of Protaetia brevitarsis were from mid June to early September, and those of Allomyrina dichotoma were from mid June to late August. These activities were mainly influenced by amount and duration of rain. They were more active when there was small amount and short period of rain in a year. Distribution depth of the 3$^{rd}$ larvae of P. brevitarsis were not affected to the temperature. But A. dichotoma were sensitively react to the temperature, almost larvae were near the surface when high temperature. The distribution of P. brevitarsis was not affected by humidity, but most of A. dichotoma were near the surface when high humidity. Larvae of P. brevitarsis usually ate their dead individuals. When we supplied as food the pork, chicken, fresh mackerel, bread, apple, and pear. They took all of these food but larvae of A. dichotoma took only bread. Two species were lived in similar environment but those feeding habit was very different.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.163-170
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• 1998

Larval morphological characters such as body color and stripe pattern were analyzed to get morphological genetic markers of beet armyworm, Spodoptera exigua (Hiibner). Body color was varied from light green to dark brown with diets. Stripe characters were classified by the presence of dorsal and lateral lines: three stripes with both lines, one stripe with dorsal line only, and zero stripe. Proportions of each stripe character increased with successive selections for its own character. Three stripe was dominant to one stripe when they were crossed. The estimated heritability in narrow sense (h2) of the stripe pattern was 0.50k0.42. About two fold more females than males were produced in zero stripe line. Stripe pattern was not significantly changed by different diets except in welsh onion which had lower proportion of three stripe individuals than that of the expected. Larval stripe pattern was also correlated with larval and pupal developmental rates and cold hardiness but not with insecticide susceptibility.

• Research in Plant Disease
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• v.15 no.3
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• pp.262-265
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• 2009

The fungus gnat, Bradysia difformis was examined for its ability to transmit Fusarium oxysporum in PDA culture. Larvae and adults of B. difformis were able to transmit the fungus as ingested and sticking. We constructed GFP-expressed mutants with Fusarium oxysporum, then feed it to larvae of fungus gnat, B. difformis. So that mycelia were placed in the alimentary canal of larva.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.475-479
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• 1992

The non-steroidal ecdysone agonist RH 5849 showed almost similar LC.o values( 18.1-26.5 ppm) at all stages of larval development of the tobacco cutworm, Spodoptera litura, when treated by a leaf-disk dipping method. The feeding-inhibition rate for the 4th instar larvae was dose-dependent, and simultaneously the weight gain of 3rd instar larvae ceased within 48 hour after feeding of the cabbage leafdisk dipped into RH 5849 4.2 ppm solution. The systemic larvicidal effect of RH 5849 was compared at cabbage and tobacco whole plant test. The $LC_{50}$ values below 20 ppm(mg/kg soil) was lasted for 15 days in cabbage, 30 days in tobacco respectively.

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.248-252
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• 1984

A human case infected with Terranova type A larva was found in Korea. The patient was a 23-year old soldier of the Korean Army and the chief complaint was acute abdominal pain. The pain was chiefly at right lower quadrant. Appendectomy was performed under the clinical impression of acute appendicitis. However, during the surgery, a nematode larva was found moving on the serosal surface of terminal ileum. The worm was 25.76mm long and O. 66mm -wide, and had the intestinal cecum reaching to anterior one-third level of ventriculus and a mucron at posterior end. Therefore, it was diagnosed as Terranova type A larva. This is the first human case of Terranova type A larva infection in Korea.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.171-178
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• 2007

Esterase isozymes were extracted from final instar larvae of M. saltuarius treated with selective diets and inhibitors. Twenty esterase isozymes were separated on 12% native-PAGE gel and stained with three different substrates(${\alpha}$-naphthyl acetate, ${\beta}$-naphthyl acetate, or ${\alpha}$-naphthyl butyrate). Interestingly, the isozymes of Est7(${\alpha}$-naphthyl acetate and ${\alpha}$-naphthyl butyrate) and Est6(${\beta}$-naphthyl acetate) were specifically activated in final instar larvae fed with the bark of Pinus koraiensis. However, we could not find any band from substrate ${\beta}$-naphthyl stearate. The esterase activities of Est3, Est6, and Est7 were inhibited by organophosphate and carbamate insecticides. In addition, The esterase activities of Est4, Est6, and Est7 were also inhibited by eserine. However, inhibition of esterase activities in methoprene, bornyl acetate, linal, cineol, and citral was not observed. However, It is necessary to reconfirm these results in vivo.