• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.11a
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• pp.136-136
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• 2002

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.2
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• pp.75-80
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• 2006

Changes in the levels of protein and free amino acids in the haemolymph of three selected races of the silkworm, Bombyx mori viz., PM, $NB_4D_2$ and $CSR_2$, were investigated during 4th moult, 5th instar and pupal period. The levels of total protein in the haemolymph, increased from first day of 5th instar till sixth day. From seventh day till spinning, the protein levels decreased in all the three races. A sustained decrease in the haemolymph proteins was observed during the pupal development in all the three races. The levels of free amino acids, which were high during 4th moult, declined through the 5th age of larval development till spinning. PM showed a relatively higher free amino acid level (3.192 mg/ml) in haemolymph followed by $NB_4D_2$ (2.601 mg/ml) and $CSR_2$ (2.35 mg/ml). The free amino acid levels decreased gradually from prepupal stage but increased again at the end of pupal period. Racial differences in the changes in the levels of protein and free amino acids in the haemolymph were observed in the larvae and pupae when subjected to two high temperature regimes of $30^{\circ}C$ and $35^{\circ}C$. The results showed that high temperature induces specific changes in the metabolism (reversible thermal stress) that have different adaptive value in different races of the silkworm. Relatively higher increase in the free amino acid levels in the haemolymph of Pure Mysore presumably provides protective cover to tissues against high temperature by an increase in osmolarity and reduction in evaporative water loss. The absence of such a mechanism may be responsible for temperature susceptibility of the bivoltine races like $NB_4D_2$ and $CSR_2$.

• Korean journal of applied entomology
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• v.27 no.1
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• pp.21-27
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• 1988

A study was carried out to investigate the morphological characteristics and life histories of H. morosa and H. diomPhalia during the period from 1984 to 1986. The head capsule width and bOdy length of H. Morosa larvae were slightly greater than those of H. diomPhalia. Otherwise, the two species looked very similar and were hard to be differentiated from each other in all life stages. H. morosa adults emerged in late June and laid eggs in soil during the period between mid July and mid August. Larvae developed by September to the last(3rd) instar which overwintered to pupate in late May. H. diomPhalia adults emerged from mid August but remained under the soil until next spring after which females laid eggs in soil from late May to early July. Larvae developed in most cases to the last instar by September and overwintered thereafter. Unlike H. morosa, they resumed feeding next April and began to pupate in late July. The egg periods of H. morosa and H. diomPhalia did not significantly differ but the larval and pupal periods of the latter were longer than those of the former.

• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.1-8
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• 2013

This study was conducted for investigation of habitat and development of indoor-rearing conditions of peacock butterfly, Inachis io (Linnaeus). Three different region, Mt. Kwangduk-san, Mt. Hae-san and Mt. Taebaek-san in Kangwon-do, was selected for investigation of domestic distribution and ecological environment of peacock butterfly. In result, there are many butterflies in the only two region, Mt. Kwangduk-san and Mt. Hae-san. On 16th April, 4 overwintered butterflies were observed in Mt. Hae-san. At the end of June and early in July, 51 individual next generation's butterflies were observed in Mt. Kwangduk-san and Mt. Hae-san. For development of indoor-rearing conditions, collected each 15 male and female peacock butterflies was reared in a room condition. Female butterflies laid eggs in the egg cluster on the underside of host-plant's leaves, Urtica angustifolia Fisch., in the ovipositioning room. We took 11 egg cluster with average $404.6{\pm}23.6$ eggs. Hatchablity of eggs was 92.3%, and the eggs hatched within $5.1{\pm}0.9$ days from the day of oviposition under high temperature, long day condition($25^{\circ}C$, 14L:10D). The larval period was $18.3{\pm}1.0$ days under high temperature, long day condition($25^{\circ}C$, 14L:10D), showing 81.0% pupal ratio. The head width of each developmental larval stage were $0.37{\pm}0.01mm$(1st instar), $0.66{\pm}0.02mm$(2nd instar), $1.07{\pm}0.05mm$(3rd instar), $1.81{\pm}0.07$(4th instar), $2.76{\pm}0.08$(5th instar). The pupal period was $8.4{\pm}0.6$ days, and the emergence rate was 87.5%.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.168-172
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• 1981

This work was carried out to study field biology of Agrotis tekienis B. in Korea for two years (1979 and 1980), The species was found to be the dominant species among cutworms giving damage to young Plants in Spring with making up approximately $80\%$ or more of cutworms collected at Suweon and Jeonju from March to early June. During April and May which is the most critical period as far as plant damage by cutworms is concerned, those of A. tokionis larvae collected were at 5th and 6th instar. A. tokionis larvae enter a summer diapause from late May to early July and Agrotis ipsilon became the dominant species. It is also suggested that A. tokionis larvae be called as the 'dark grey cutworm', based upon its larval body color.

• Journal of Sericultural and Entomological Science
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• v.23 no.2
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• pp.11-36
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• 1982

Forty-nine plant species as additives to silkworm artificial diet and 5 species as cellulose sources for artificial diet were screened for their economic values as feed-resources for the silkworm. Feeding response to artificial diet was tested on 82 silkworm strains. The effect of rearing conditions on feeding response and enzyme activities in the silkworm was investigated. The results were summarized as follows. 1. Seven species out of 49, Vigna sinensis ENDL, Ipomoea vatatas Lamarck, Cyperus anuricus Var. Laxus, Alnus japonica Stendel, Trifolium repens L, Prunus serrulata Lindley. Var, Glycine max L increased feeding response, compared with the basic formula of artificial diet. 2. The economic values of Vigna sinensis ENDL, Ipomoea vatatas Lamarck, Cyperus anuricus Var. Laxus, Ainus japonica Stendel, Cassia tera L, Erigeron canedensis L as feed-resources for artificiale diet were recognized, through feeding experiment during the entire larval stage. 3. Mulberry cellulose showed the best results in rearing and cocoon characteristics. 4. The extent of feeding response varied according to strains and varieties. Varieties in japanese strains showed higher feeding response than those in chinese and european varieties, with considerable variations among a varieties in strains. 5. The begining of 4th instar seems to be a proper time to convert from mulberry to artificial diet, or artificial diet to mulberry, however the middle of 3rd instar seems acceptable. 6. The optimum temperature for artificial diet rearing is 30$^{\circ}C$ during the period of 1st-3rd instar and 28$^{\circ}C$ for 4th-5th instar. 7. Electrophoretic isozyme patterns of esterase and acid phosphatase on agarose gel, as affected by strain. rearing temperature and feed-resources, were observed as follow. (1) Isozyme patterns of mid-gut esterase varied, depending on instar. One or two more isozyme bands were observed in the larvae than feed on the mulberry fed for the artificial diet. (2) A strain, chinese-15 with a higher feeding response, had 1∼2 more bands than chinese-60 with a lower feeding response. (3) Five bands of mid-gut esterase in 3rd and 4th instar larvae reared at 28$^{\circ}C$. and 4 for 3rd instar and 6∼7 for 4th instar larvae at 35$^{\circ}C$ were observed. (4) No similar esterase bands could be found among mid-gut, blood and silkgland. There are five esterase bands in the midgut, one in blood and three in silkgland. (5) There was rather small digerence in acid phosphatase types of mid-gut and blood according to varieties and rearing temperature. No active band was shown in silkgland. In midgut, there was one acid phosphatase band at 3rd instar, two at 4th instar and three at 5th instar. In blood, one active band at 3rd or 4th instar and three bands at 5th inster wire detected.

• Journal of Sericultural and Entomological Science
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• v.15 no.1
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• pp.9-14
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• 1973

This study has been carried out to investigate proteinase activity of digestive juice and sucrase activity of midgust tissue in the 5th day of the 5th instar influenced by the dietary composition (quantitative ratio between carbohydrate and protein) and tile rearing temperature during the 4th moulting period. The larvae grew on three kinds of semi-synthetic diet. The A-diet has more carbohydrate than the others, the B-diet has carbohydrate in 1 : 2 with protein, and the C-diet has more protein than the others. All the diets were kept at 16$^{\circ}C$, 25$^{\circ}C$ and 33$^{\circ}C$ during the 4th moulting period. Proteinase activity of digestive juice at the 5th day of the 5th instar was analyzed by Anson's hemoglobin method. Sucrase activity of midgut tissue at the 5th day of 5th instar was analyzed by Somogyi-Nelson's method. The results were as follows. 1. The dietary composition influencing contents of blood sugar was not related to the rearing temperature during the 4th moulting period. The contents of blood sugar appeared to increase in A-diet, B-diet and C-diet order, while proteinase and sucrase activity were stronger in C-diet, B-diet and A-diet order. 2. All kinds of diets showed almost the same fact that proteinase activity at 16$^{\circ}C$ was stronger than that at 32$^{\circ}C$. 3. It was found that sucrase activity became gradualy stronger at 32$^{\circ}C$, 25$^{\circ}C$ and 16$^{\circ}C$ in order in all kinds of diets. 4. There was an interaction in proteinase activity between the dietary composition and the rearing temperature in male larval digestive juice during the 4th mouiting period. On the other hand, there was an inter-acion in sucrase activity between the dietary composition and the rearing temperature in both female and male larval midgut tissue during the 4th moulting period.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.1-4
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• 2011

This study was conducted to test the use of colored cocoon silkworm, Golden Silk, as a host for the fruiting body production of Cordyceps mushroom. Golden Silk variety had a shorter larval period than Yangwonjam at $25.3^{\circ}C$ and 78.5% RH: The average larval period of the Golden Silk was 24 days and 7 hr, and that of the Yangwonjam was 24 days and 15 hr. In the infection test of I. tenuipes on silkworm, the larval period of normal silkworms was longer than the silkworms inoculated with I. tenuipes in both Golden Silk and Yangwonjam. The pupae survival percentage of Golden Silk was 94.4%, whereas it was 91.9% in Yangwonjam. Golden Silk had a higher pupation rate than Yangwonjam. The pupation rate of normal silkworms was about 5% higher than that of silkworms inoculated with I. tenuipes. Infection rate of I. tenuipes into larvae of 5th instar newly exuviated silkworm was 93.8% in Golden Silk, and 96.9% in Yangwonjam. Synnemata production of I. tenuipes was better in Yangwonjam with an incidence rate of 99.8% than Golden Silk with 98.6%. The average synnemata weight of Golden Silk was 1.12 g and that of Yangwonjam 1.29 g. Golden Silk had a lower synnemata weight than Yangwonjam. But no significant difference was observed in synnemata weight varieties. The synnemata of I. tenuipes produced on pupae were white or milky-white in color, and similar in shape and color to wild synnemata collected in Korea.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.7-14
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• 2004

This study was carried out to survey and confirm the occurring sites of Parnassius bremeri in Korea, and to investigate ecological characteristics to develop a mass rearing technique. In the field survey, adults were found in the two previously known sites in Gyungnam Province and another site was newly found in Samcheok, Gangwon Province. Emergence period of adults was from middle of May to middle of June. Oviposition took place on various material, including hostplant, debris, dead leaves, etc. Eggs were laid singly, up to 126.7 eggs per female. The egg-period was 221.3${\pm}$2.3 days, eggs were hatched from 11th to 22nd of January in the natural condition, and started to feed for about 10 days after hatching. Survival rate of the 1st larvae was 67.6%. Developing period of each instar in the insectary (25$^{\circ}C$, 75% RH, 16L:8D) was 11.2 days for the 1st instar, 7.3 days for 2nd, 12.8 days for 3rd, 16.2 days for 4th, and 18.2 days for 5th, and the pupal period was 21.3 days. The average longevity of adults was 26.2 days. Oviposition rate was higher in the natural condition with enough space to fly for 3♀ : 1 ♂ coupled, at least 3 ${\times}$ 3${\times}$4 m-sized room, than in smaller cage. In a comparison of the preference for visiting on sugar source, black sugar and fructose were effective.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.69-75
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• 1994

Through the histological and anatomical investigation of silkworm gonad, N. bombycis infection was found to begin from the peripheral region of ovarial sheath or testicular sheath, then, the pathogens spread to the inner portion. Peroral inoculation with purified spores of N. bombycis to 2nd instar larvae at dosages around 106-8/㎤ of artificial diet resulted in the extremely extended larval survival as long as 15 to 22 days of 4th instar. The growth of ovarioles was confirmed in the 10 to 14 day old larvae, oogonia developed into oocytes and nurse cell against heavy infection of the ovary. Gonads rarely obstructed oogenesis and spermatogenesis in the pupae failed in adult eclosion. Light infection of female hosts effected insignificantly on the ovarial development, however, recorded 100% transmission of the pathogens to the progeny populations. Conclusively, ovarial inflection of silkworm induce transovarial transmission begins around 2~3 day old pupae when ovarioles extruded out to hemocoel, and the infection period thought to be continued until the stage of eggs complete shell formation in the ovariole.