• Journal of Sericultural and Entomological Science
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• v.24 no.1
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• pp.25-27
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• 1982

The use of fumigation of Neo-PPS was tested for the larval disinfection and at the same time for easy handling and effective chemicals for larval disinfection. The results obtained are as follows: 1. There was no decrease of cocoon yield in spring season due to chemical damage by application of Neo-PPS fumigation to the disinfection of the silkworm except 2,4 and 6 hours' treatment everyday and 6 hours'/ twice/instar treatment as compared with the control. 2. There was no significance in pupal percent between treatments and control in spring season except 6 hours' treatment everyday. 3. No chemical damage seemed to give rise to percentage of cocoon shell in all treatments.

• Journal of Life Science
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• v.28 no.5
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• pp.563-568
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• 2018

The insect industry is a promising agricultural resource and expected to grow steadily. In Korea, Gryllus bimaculatus and the larvae of Tenebrio molior, Protaetia brevitarsis, and Allomyrina dichotoma were listed as general food ingredients. As interest in these edible insects increases, rearing techniques and nutritious food sources are needed for mass production. In this study, wheat bran, dog feed, and pig feed were investigated for their effects on the larval growth of P. brevitarsis and A. dichotoma. When fermented sawdust with 30% wheat bran was used, the larval survival rate of P. brevitarsis and A. dichotoma (p=0.244341 and p=0.007966, respectively) and growth rate (p=0.001400 and p=0.000051, respectively) were significantly lower than those of the control (fermented sawdust with no supplement). Therefore, fermented sawdust with a high density of wheat bran was inappropriate for both insects. When fed fermented sawdust with 2.5 or 5% of dog and pig feed, the survival rate and growth rate of the larvae were higher than those of the control. Interestingly, the maximum larval weight with 2.5% dog feed was increased by $3.35{\pm}0.10g$ and $32.59{\pm}0.79g$ for P. brevitarsis and A. dichotoma, respectively. In addition, the larval period of both was shorter than that of the control by 40 days or more. Therefore, it is considered that animal feed can be used as a feed source for these edible insects.

• Journal of Ecology and Environment
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• v.44 no.1
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• pp.45-53
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• 2020

Background: The black soldier fly (Hermetia illucens) is gaining attention as an efficient decomposer of food waste. However, recalcitrant compounds such as plastics mixed into food waste may have negative effects on its growth and survival. Moreover, its efficiency of food waste degradation may also be affected by plastics. In addition, salt (NaCl) can also be present in high concentrations, which also reduces the efficiency of H. illucens-mediated food waste treatment. In this study, we assessed the growth of black soldier fly larvae (BSFL) reared on food waste containing polyethylene (PE) and polystyrene (PS) and NaCl. The weight of BSFL was measured every 2-4 days. Survival and substrate reduction rates and pupation ratio were determined at the end of the experiment. Results: The total larval weight of Hermetia illucens reared on food waste containing PS was greater than that of the control on days 20 and 24. However, the survival rate was lower in the group treated with 5% PS, as was substrate reduction in all PS-treated groups. The weight of BSFL reared on food waste containing PE was lower than that of the control on day 6. PE in food waste did not affect the survival rate, but the pupation ratio increased and substrate consumption decreased with increasing PE concentrations. Regardless of the plastic type, the addition of NaCl resulted in decreased larval weight and pupation ratio. Conclusions: Larval growth of black soldier fly was inhibited not by plastics but by substrate salinity. Additional safety assessments of larvae reared on food waste containing impurities are needed to enable wider application of BSFL in vermicomposting.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.295-299
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• 2012

The present study was performed to determine the infection status of anisakid larvae in marine fish collected from 3 sea areas of the Republic of Korea. Total 86 marine fish (8 species) collected from the East Sea (Goseong-gun, Gangwon-do), 171 fish (10 species) from the South Sea (Sacheon-si, Gyeongsangnam-do), and 92 fish (7 species) from the Yellow Sea (Incheon Metropolitan City) were examined by both naked eyes and artificial digestion method. Among the total of 349 fish examined, 213 (61.0%) were infected with 8 species of anisakid larvae, i.e., Anisakis simplex, 6 types of Contracaecum spp., and Raphidascaris sp., and the mean larval density was 13.8 per infected fish. Anisakid larvae were detected in 45 fish (52.3%) from the East Sea, 131 fish (76.6%) from the South Sea, and 37 fish (40.2%) from the Yellow Sea. The average numbers of larvae detected were 4.0, 16.6, and 15.9, respectively. Anisakis simplex larvae were detected in 149 fish (42.7%), and the mean larval density was 9.0 per infected fish. They were found in 26 fish (30.2%) collected from the East Sea, 96 fish (56.1%) from the South Sea, and 27 fish (29.3%) from the Yellow Sea. The average numbers of larvae detected were 2.9, 10.3, and 10.5, respectively. Conclusively, the present study suggests that the infection rate and density of anisakid larvae are more or less higher in the fish from the South Sea than those from the East Sea or the Yellow Sea.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.1
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• pp.69-73
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• 2001

The effect of topical application 100,300 and 500 $\mu$g/ ml with Mineral Salts of magnesium sulphate and potassium nitrate on economic parameters was ana- lyzed following treatment of last larval stadium. The treated larvae showed significantly decreased larval weight and silk gland weight in all the treated groups along with other decreased Iarval, cocoon and adult parameters. The female cocoon weight was significantly decreased in all the treated groups with decreased female cocoon shell weight and male cocoon weight at 300 and 500$\mu$g/ml respectively. The length and weight of filament was significantly decreased at 300 and 500 $\mu$g/ml respectively and denier at 500 $\mu$g/ ml. The fecundity decreased significantly in 300 and 500 $\mu$g/ml treated groups when compared with the corresponding parameters of the carrier control.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.15-19
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• 2003

The study evaluated the influence of feeding different maturity leaves i.e., tender, medium, coarse and mixed leaves of three different maturity during late larval stages of new bivoltine race $(CSR_{3} {\times} CSR_{6})$. The data were compared with shoot feeding and control batches in which conventional feeding method was followed. The most of the larval and cocoon characters were recorded significantly higher in tender leaves fed batches followed by T4 batch (2 times tender and 1 time coarse leaves). Lowest melting percentage (1.494%) was recorded in T4 and highest (4.69%) was recorded in coarse leaf (T3) fed batches. Significantly higher post cocoon parameters viz., average filament length, non-breakable filament length, renditta and raw silk percentage were recorded in tender loaves fed batches.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.532-536
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• 2004

Due to the fourth-instar larvae of C. riparius have a sensitive to ecdysteroidal molting hormones for the life cycle developments, accordingly the emerged adult affected corresponding to larval phase's environments. The emerged female from larval phase exposure to DEHP observed a fact body and clumsy fling behavior in females. The body volume of treated female groups was clearly larger than that of control fe- males. In the 2D/E gel 1108 protein spots were identified. The visualized protein spots allowed extraction of 27 protein spots differed more than 3 fold in DEHP treated animals, which was approximately 2.4％ of the total protein spots. In this view, the body volume (or morphological characters) was well observed and detected faster than physiological detection for various EDCs. In this study, the body volume as a detecting po-int for EDCs suggested a bio-marker in individual levels.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.173-177
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• 1996

Bacillus thuringiensis subsp. morrisoni PG-14 is a gram-positive soil bacterium producing mosquitocidal parasporal inclusions composed of several crystal proteins. Among these crystal protein genes, cryIVD gene is one of major component which has 72 kDa in size. However, these parasporal inclusions sink quickly from the surface of water where mosquito larval feeding occurred. To develope mosquitocidal cyanobacterium, therefore, we constructed the expression vector, pCYASK 5-1 harboring cryIVD gene. The expression vector, pCYASK5-1 was transformed into the cyanobacterium Syne- chocystis PCC6803 reported as a natural mosquito larval food source and the transformants were selected with kanamycin. Expression of IVD gene in transformant was characterized by SDS-polyacrylamide gel electrophoresis (PAGE) and immunoblot analysis. The mosquitocidal activity of a transformant was determined with Culex tritaeniorhynchus. The results showed that, the transformed cyanobacterium is toxic to mosquito larvae and will be expected as a potential agent that is used for mosquito control.

• The Korean Journal of Ecology
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• v.21 no.6
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• pp.799-804
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• 1998

laboratory experiments were conducted to determine the effects of Dimilin, an insect growth regulator which acts to inhibit chitin synthesis, during the larval development of liocarcinus corrugatus Pennant. The larvae was exposed to control (10 ppb acetone sea water and untreated sea water solution) and five concentrations 0.1, 1.0, 5.0, 10.0 and 25.0 ppb of both TG and WP-25 formulations of Dimilin from the hatching to the megalopal stage, and the effect of Dimilin on development of the larvae were determined. Two formulations (TG and WP-25) had different effect on the different stages in L. corrugatus. and early stage larvae of L. corrugatus were more sensitive to TG than to WP-25. Concentrations of diflubenzuron >5.0 ppb are lethal to L. corrugatus larvae upon chronic exposure. Lethal concentrations are defined here as those in which less than 10% of the larvae survived to the megalopal stage. However, Dimilin (TG and WP-25) showed no significant effects on developmental time of L. corrugatus larvae.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.69-78
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• 1965

1. In younger larval stages, the incubation period of Spicaria pracina was showed to generally last for 8 days after the inoculation of 1st instar, for 11 days after that of 2nd instar, and for 12 days after that of 3rd instar. 2. The more the inoculum of spore is, the more silkworm jundices appear severely throughout all stage except 1st instar. 3. Especially in matured larval stages, more death rate due to silkworm jundice was showed to appear than that due to green muscardine and the more the larvae became mature, the more the loss due to jundice were severe. 4. Among other inoculum, the control by 5 per cent cerisan lime resulted in getting the best economical effect while this chemicals did harm to the silkworms, being of 20.1 per cent death rate.