• Journal of Sericultural and Entomological Science
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• v.44 no.2
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• pp.82-86
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• 2002

Silk sericin powder was prepared by mechanical treatment from culled-cocoon extract of Bombyx mori silkworm. The physical and structural characteristics of sericin powder were investigated by instrumental analysis. The solubility of sericin powder was decreased nearly half of sericin lyophilized. Amino acid analysis showed that arginine content was decreased from 3.72% to 0.03∼0.07%. XRD showed that molecules of sericin were somewhat regularly arranged by mechanical treatment. On the other hand, FT-IR showed the molecular vibration of silk sericin was not induced by mechanical treatment. Thermal properties also did not changed.

• International Journal of Industrial Entomology and Biomaterials
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• v.29 no.1
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• pp.128-134
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• 2014

Nesolynx thymus Girault (Hymenoptera: Eulophidae) is one among 20 hymenopteran parasitoids reported to attack the uzi fly, Exorista bombycis, which in turn infests the silkworm, Bombyx mori accounting a cocoon yield loss of 10-20%. A host of factors viz., age and size of host, age and size of parasitoid, availability of host, temperature and quality of host are reported to influence the reproductive efficiency of the parasitoids. In the present study an attempt was made to record the influence of foraging parasitoid density on their reproductive performance. Three day-old uzi pupae were offered to varying numbers (1 - 10) of 2 day old Nesolynx thymus adults for parasitization. The progeny production per pupa (84.44 - 132.77) increased significantly with increase in the number of foraging parasitoid adults (1 - 10) however, progeny production per female decreased. The sex ratio (M : F) (1:25.49 - 1:1.53) decreased significantly with increase in foraging parasitoid adults. The morphometric parameters except female abdomen width of first generation parasitoid showed significant negative correlation with number of foraging adults. However, correlation between the parasitoid size in first generation and their reproductive performance was nonsignificant.

• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.1
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• pp.9-13
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• 2019

In this study, 4 different types of GBR membrane were undergone for bio-degradability test; Silk mat from silkworm cocoon (TDI), silk mat from flatwise-spun (FS), collagen membrane (OssGuide), and dPTFE membrane (Cytoplast). Each material was segmented in 10.00 mm length and 0.3 mm thickness. The samples were put into the normal saline at $37^{\circ}C$ for 2 weeks. After that, yield strength and tensile strain were measured and compared them with those of before treatment. The morphology of the membranes was observed by SEM. Tensile strain of FS was significantly increased at 2 weeks' normal saline treatment (P=0.018). When compared to OssGuide, TDI and FS showed significantly higher tensile strain at 2 weeks' normal saline treatment (P<0.05). In the SEM images, there were no significant changes in Cytoplast, TDI, and FS after 2 weeks' treatment. However, OssGuide showed damaged surface after 2 weeks' treatment. In conclusion, both TDI and FS did not have any evidence of biodegradability at 2 weeks' observation in normal saline treatment. However, OssGuide showed more than 20 % decrease in yield strength and tensile strain.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.41-46
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• 1965

Author investigated the effects of a grate type mounting on. the pupae, moth and deposit of silkworm eggs. The results are as follows. 1) The grate type mounting was more useful for the silkworms to spin the cocoons transversely than the other type. 2) Many abnormal pupae appeared in the control, and in next generation all the silkworm characters of them were poor. 3) The fact which many dead pupae occurred in the control seems to be that the cocoons spun vertical1y did harm to the physiological reactions of the pupae. 4) The moth rate emerging out of the cocoons was higher in the grate type mounting than in the control. 5) Many moths which laid normal eggs were in the grate type mounting, and also laid a lot of eggs. Therefor, author made an infference that the grate type mounting had accelerated the laying eggs. 7) The total weight of eggs produced from 1000 cocoons was heavier in the grate type mounting(index=100) than in the control (index=85). As shown in table of analysis of vanriace, above phenomenon might be relative with one of the reasons why the cocoon spun transversely could be more produced in the grate type mounting than in the control. 8) Even though the grate type mounting costs higher than the other one, it may be available because the egg weight per unit was considerably heavier in its treatment. So the cost of egg production will become cheaper.

• Journal of Sericultural and Entomological Science
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• v.48 no.2
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• pp.37-40
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• 2006

A new silkworm variety "Daepoongjam" for spring rearing season is $F_1$ hybrid between Jam151, a Japanese race bred from introduction breeding and Jam152, a Chinese race from introduction breeding. In the local adaptatability test performed at 8local areas in spring of 2005, the heavy cocoon yield of "Daepoongjam" was recorded 6% higher than "Kumokjam". The concentration of Deokynojirimycin (DNJ) was measured 4.22 mg in "Daepoongjam", similar to "Kumokjam" (4.26 mg). In the Peacilomyces tenuipes production ability test, the pupal weight of "Daepoongjam" was 1.61 g/individual 13% heavier than "Kumokjam" (1.41 g/individual)

• Journal of Sericultural and Entomological Science
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• v.15 no.2
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• pp.55-60
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• 1973

The statistical interpretations are on the correlations and the linear regressions between the various meteorological conditions the branch Pusan-Observatory of the National-Central-Meteorological-Observatory had measured from 1930 to 1962, and the production of silk worm cocon that the Section of Sericulture in the Ministry of Agriculture ＆ Fishery had recorded from 1930 to 1962 in Gyung Sang Nam Do Korea. These were most in proportion to the sun shine time, an inverse proportion to the atmosphere humidity and the lowest temperature, in proportion to the mean temperature, the highest temperature and the amount of the rain fall. The correlations and linear regressions between the various meteorological factors to control the production of the silkworm cocoon of both per a box of the silk worm egg and per 10a of mulberry field was as follows. (1) The production of the spring silk worm cocoon was dicided by the various meteorological factors. 1. This was in proportion to the total sun shine time between 5 and 6 month. r=0.40＊-(0.42$^{**}$) Y=0.0269$\chi$＋6.46-(0.2795$\chi$＋10.25) 2. This was an inverse proportion to the total amount between 5 and 6 month atmosphere humidity. r=-0.49$^{***}$-(-0.40＊) Y=-0.2989$\chi$＋62.77-(0.1474$\chi$＋31.86) 3. This wasin proportion to the total rain fall amount between 6 and 7 month. r=0.47$^{***}$-(0.44$^{***}$) Y=0.0037$\chi$＋16.42-(0.0035$\chi$＋8.35) (2) The production of the autumn silk worm cocoon was decided by the various meteorological factors. 1. This was in proportion to the total sun shine time between 5 and 6 month. r=0.37＊-(0.45$^{***}$) Y=0.0205$\chi$＋5.51-(0.0173$\chi$＋2.41) 2. This was an inverse proportion to the total amount between 5 and 6 month atmosphere humidity. r=-0.41$^{**}$-(-0.42$^{**}$) Y=-0.2085$\chi$＋45.33-(-0.0599$\chi$＋12.17) 3. This was in proportion to the total of rain fall amount of 6 and 7 month. r=0.48$^{***}$-(0.35＊) Y=0.0050$\chi$＋11.97-( ) 4. This was in proportion to the total sun shine time among 3, 4, 5, and 6 month. r=0.51$^{****}$-(0.49$^{***}$) Y=0.0178$\chi$-1.27-(0.0096$\chi$-3.60) 5. This was an inverse proportion to the total amount among 3, 4, 5, and 6 month atmosphere humidity r=-0.41/$^{**}$-(-0.44$^{***}$) Y=-0.0938$\chi$＋40.14-(-0.05693$\chi$＋20.49) 6. This was in proportion to the total of a year sun shine time. r=0.58$^{****}$-(0.43) Y=0.0037$\chi$＋5.35-(0.0015$\chi$＋1.02) (3) The production of the next year spring silk worm cocoon was decided by the this year various meteorological factors. 1. This was in proportion to the total of a year sun shine time. r=0.55$^{****}$-(0.52$^{****}$) Y=0.0034$\chi$＋12.02-(0.0025$\chi$＋3.84).>＋3.84).3.84).>＋3.84).

• Journal of Sericultural and Entomological Science
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• v.9
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• pp.49-66
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• 1969

Eri-silkworm is known as a tropical insect where as poly-voltine type in that area. It eats caster oil plant leaves which are cultivated as an every year cultivatable seed oil use in this country, even though it grows for many years in tropical countries. That is why, farmers have freedom for its cultivation in any year if they want. Therefore, eri-silkworm rearing service is flexible for its diet procurment as wish of farmer. The eri-cocoon price or economical fluctuation may be reactable for the rearing work not like as mulberry cocoon. Fortunately, it also eats cynthia tree leaves. Standing from such a easy condition, the authors have studied about this problem since 1963 to develope a culturing method of eri-silkworm rearing in this country and the authors brought out the matters to be produced as an industry scale. Here, the authors summarized their works of the results covering with thirty three work tables. The obtained results are as follows.

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.1-25
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• 1969

Since widely use of anthracite for the radiating purpose in a rearing room in Korea, the weakness of silkworm, poor uniformity of the worm growth, the increase of missing worm ratio, unusual cocoon assorting ratio, and the decrease of cocoon layer ratio have been realized by the author, therefore, he has started out to search the mechanism of these evil influences regarding with various gas densities and terms of the gas treatment which will be supposed to be a warning for temperature control during the silkworm reading work. Among the anthracite gas components, CO or SO$_2$ influence and their complexed harm effect were investigated through the use of anthracite gas, CO and SO$_2$ gas. Meantime, each treatment was applied, separately, during the worm egg stage, young instar, adult instar and whole instar, because the harm intensity for any improperable rearing condition is flexible by the growing stages. Meantime, the gas density and term variation were applied for the above each treatment such as in case of anthracite and CO gas, the following treat methods were used. 1) 0.06% for 30 mins. 2) 0.06% for 1 hour. 3) 0.1% for 1 hour. 4) 0.15% for 1 hour. on the other hand, SO$_2$ gas was used as 1) 120ppm for 30 mins. 2) 200ppm for 30 mins. 3) 400ppm for 30 mins. The measurement of gas density was proceeded by using CO tester (Carbon Monoxide Indicator) and SO$_2$ tester (Indicator Sampler Cgf) which could keep any specific density before each treatment.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.335-345
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• 2009

Effect of four nematicidal herbal extracts (Daphne genkwa, Eugenia caryophyllata, Quisqualis indica and Zingiber officinale) and 3 acricidal herbal extracts (Pharbitis nil, Xanthium strumarium, and Desmodium caudatum) on entomopathobenic nematodes [Steinernema carpocapsae Pocheon strain (ScP) and Heterorhabditis sp. Gyeongsan strain (HG)], silkworm (Bombyx mori), and ground beetles (Synuchus sp.) were investigated in the laboratory and field. D. genkwa was highly toxic to SCP and HG (100% mortality) at the concentration of 5,000 ppm in X-plate. All the infective juveniles of HG were dead after 3 days by E. caryophyllata and Q. indica. The mortality of ScP and HG was below 10% by D. genkwa, D. caudatum, E. caryophyllata, Q. indica and Z. officinale at the concentration of 1,000 ppm two days after treatment while mortality of HG was 62.8% by D. genkwa at the concentration of 1,000 ppm in X-plate. However, 1,000 ppm had not effect on nematode survival and pathogenicity of ScP in sand column. On the contrary, E. caryophyllata had effect on pathogenicity of HG. Mean number of dead Galleria mellonella larva of HG was 0.5 in E. caryophyllata treatment. Q. indica did not effect silkworm reared on mulberry leaves at the treatment of 1,000 ppm in 10 days after treatment. However, there were 20.0 and 100% mortalities in the treatment of D. genkwa 3 and 10 days after treatment, respectively. The weight of silkworm was low in D. genkwa and did not pupate. The weight of pupa and cocoon were not different in E. caryophyllata, P. nil, Q. indica, X. strumarium and Z. officinale. D. genkwa, E. caryophyllata, P. nil, Q. indica and Z. officinale had no effect on ground beetles, Synuchus sp. in forest soil.

• 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.