• 한국잠사곤충학회지
• /
• 제36권1호
• /
• pp.26-29
• /
• 1994

누에에 유약호르몬 유사물질과 인슐린의 병용처리에 의한 효과를 알아보기 위하여 4령 탈피후 48시간째 methoprene을 처리하고, 5령 탈피후 72시간째 인슐린을 처리하여 시험한 결과 유충기간이 현저하게 길어지고 유충체중, 견사선무게, 전견중, 견층중, 증가하였으며, 발아비율과 산란성이 매우 향상되었다. 그리고 전견중은 암(기호)이 17%, 수(기호)가 20% 향상되었고 견층중은 암(기호)이 18%, 수(기호)가 32% 각각 더 무거워졌다.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제2권2호
• /
• pp.111-117
• /
• 2001

Screening of fifteen bivoltine silkworm breeds of Bombyx mori Linn at a temperature of $31{\pm}1^{\circ}C$ and relative humidity of 85${\pm}$5% resulted in the identification of eight thermo-tolerant breeds. The survival and cocoon shell ratio of the tolerant breeds ranged from 72.7 to 78.7% and 20.0 to 20.1% respectively. The tolerant breeds comprised of four oval breeds and four dumb-bell breeds. Eight foundation crosses prepared by crossing the oval and dumb-bell parents among themselves were screened at a temperature of $31{\pm}1^{\circ}C$ and relative humidity of 85{\pm}5%. The performance of the foundation crosses on 11 economic characters were analysed by employing Multipie Trait Evaluation Index method. Four foundation crosses which scored average index value > 50 were selected as breeding parents and breeding initiated for the evolution of thermo-tolerant bivoltine silkworm breeds. The methodology and the results of the foundation crosses reared both at 31{\pm}1$^{\circ}C$ and at $25{\pm}1^{\circ}C$ temperatures, are discussed.

• 한국잠사학회:학술대회논문집
• /
• 한국잠사학회 2002년도 Join Meetings of Korean Society of Sericultural Science and Japanse Society of Sericultural Science
• /
• pp.95-95
• /
• 2002

No Abstract, See Full Text

• International Journal of Industrial Entomology and Biomaterials
• /
• 제34권1호
• /
• pp.6-10
• /
• 2017

Dissolution of Antheraea yamamai silkworm cocoon was carried out in various solvent systems with various dissolving conditions including dissolution salts, salt concentration, dissolving temperature, and time. General chaotropic salt for Bombyx mori silk fibroin does not work for A. yamamai silkworm cocoon. Lithium bromide 9.3 M at $100^{\circ}C$ also does not work to dissolve wild silkworm cocoon. However, 9 M of lithium thiocyanate treatment at $100^{\circ}C$ induced 100% dissolution of wild silkworm cocoon. But it could not be dissolved lower than $60^{\circ}C$. Like lithium thiocyanate, less than $60^{\circ}C$ treatment with molten calcium nitrate 4 hydrate could not dissolve wild silkworm cocoon. As the dissolution temperature increased up to $100^{\circ}C$, the solubility of wild one was reached over 90%. SDS-PAGE showed broad tailing stream pattern that means the molecule of wild silk was depolymerized with dissolution temperature and time. From the above results, the best chaotropic salt for A.yamamai silkworm cocoon is calcium nitrate 4 hydrate.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제13권2호
• /
• pp.73-77
• /
• 2006

Combining ability and hybrid vigour analysis was carried out in hybrids between newly developed non-susceptible lines to BmDNV1 and popular bivoltine breeds for certain quantitative traits viz. Pupation rate, Cocoon yield, Cocoon weight, Cocoon shell weight and Cocoon shell ratio, Survival rate against BmIFV and BmNPV. General combining ability (GCA) effects revealed that among the lines CSR2DR was found good general combiner exhibiting significant GCA effects for six characters, out of seven traits evaluated. Among testers CSR28DR was found as good combiner exhibiting significant GCA effects for six traits. Out of 36 hybrids made between $resistant{\times}resistant,\;resistant{\times}susceptible\;and\;susceptible{\times}susceptible$ breeds, one hybrid $CSR21DR{\times}CSR28DR$ exhibited significant SCA effects for six traits. The selected hybrid $CSR21DR{\times}CSR28DR$ also exhibited significant positive heterosis and heterobeltiosis expressions for maximum traits and could be exploited as commercial silkworm hybrid resistant to important viral diseases.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제14권1호
• /
• pp.23-32
• /
• 2007

The nature of genetic variation and diversity among the 65 multivoltine silkworm genotypes was evaluated for 16 post cocoon characters. The components of genetic variation revealed higher PCV (60.487%) and GCV (44.56%) for evenness (variation 1) followed by cohesion (PCV=55.38%, GCV=40.36%) and non-broken filament length (PCV=32.05%, GCV=31.28%). The higher heritability ($h^2$ in broad sense) was observed for boil-off loss (95.6%) followed by non-broken filament length (95.22%). The both genotypic and phenotypic correlation indicated significant positive correlation of filament length with non-broken filament length, silk recovery, raw silk, neatness, and low neatness; and negative correlation with denier, renditta and silk waste. The principal component analysis (PCA) revealed 75.381 % of total variance from the five principal components extracted. On the basis of Mahalonobis' $D^2$ values (Ward's minimum variance), the sixty-five multivoltine silkworm genotypes were classified in to 9 clusters with substantial inter and intra cluster distances. Number of genotypes included in different clusters varied from 3 to 17. The results indicated that the optimum distance obtained in cluster VII (15.059) along with higher cluster mean values especially for filament length, non broken filament length, renditta, silk recovery, silk waste, and raw silk emphasized the utilization of these genotypes in the conventional silkworm breeding programme for improvement of multivoltine silk fibre quality. The possibility of exploiting genetic variation in post cocoon traits for efficient breeding programme is discussed.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제10권2호
• /
• pp.107-117
• /
• 2005

Oral supplementation of minerals mixture of potassium bromide and nickel sulphate on $CSR_2,\;CSR_4\;and\;CSR_2{\times}CSR_4$ crossbreed races with different concentrations (70, 110 and $160\;{\mu}g/ml$) were fed to the fifth instar larvae. Two of the four normal feeds per day was substituted with treated leaves fed to silkworm at fifth instar larvae. The controls were fed with the leaves sprayed with distilled water and normal leaves. The $CSR_4$ race treated larvae showed a significant increase in silkgland weight, cocooning percentage, female cocoon weight, male cocoon weight, male cocoon shell weight, male cocoon shell ratio, filament length, filament weight, denier, fecundity, number of eggs per ovariole and length of the ovariole when compared with those of the corresponding parameters of the carrier control, whereas in $CSR_2\;and\;CSR_2{\times}CSR_4$ crossbreed races showed a significant increase in larva1 weight and other parameters similar to that of $CSR_4$ race. The results suggested that the silkgland showed good response to minerals mixture of potassium bromide and nickel sulphate only in $CSR_4$ race when compared with those of other two races of the silkworm, B. mori.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제18권1호
• /
• pp.1-7
• /
• 2009

Quality of seed in the mulberry silkworm, Bombyx mori (L.) is determined by many important factors, wherein unfertilized eggs play an important role. Unfertilization of eggs are caused by several reasons such as, abnormality in the sexual organs of the male and female, abnormal development of the micropylar end of the egg, unfavorable environmental conditions during spinning, cocoon preservation, imperfect handling of moths, mating, ovipostion, cold storing of pupae / moths and indiscriminate use of male moths etc. Though the presence of unfertilized eggs would in no way affect the fertilized ones and their quality directly, the frequency of their occurrence underrates the quality and brings down the hatching percentage. Lower the occurrence of unfertilized eggs, higher is the rating of seed quality. Of the various intrinsic and extrinsic factors and events involved in egg deposition of an adult silk moth, mating is an instinct and a biological obligation for the ultimate perpetuation of the species and a must to provide stimulus for oogenesis and bring about biochemical changes in the spermatophore of the silkworm in order to ensure the presence of sufficient number of normal sperms and testicular fluid in the female reproductive organ, activating ovulation and accelerating oviposition behavior and egg deposition. An attempt has been made in this article to briefly elucidate the characteristics of unfertilized eggs, causes of their occurrence and its impact as well as the significance in silkworm seed production.

• 한국잠사곤충학회지
• /
• 제42권1호
• /
• pp.10-13
• /
• 2000

The objective of this research was to characterize of the silkworm that might be recognized to the Korean native strains. The eleven strains of Korean race used in this study, which is cultured in Korea and Japan seri-cultural research organs. Most of Korean varieties were three molting and univoltine, comparatively longer larval duration than the trimolter general. The egg characters of varieties showed short-eliptic shape and dark brown egg color except for a few varieties which shows greenish dark brown. Also, most of varieties were showed the plain(p) and moricaud( $p_{M}$) in larval markings. Moric marking of the varieties also consist of innumerable dark grayish brown lines and dots, though somewhat darker and lighter than that of the wild silkworm, Bombyx mandarina. Cocoon characters variations of varieties were seen in the size, color and shape. 8 varieties were colored cocoon, i.e., yellow, greenish yellow and light green etc., the others were white cocon. The shape of cocons were consisted of constricted shallowly in the middle and attenuated at one or both ends of cocoon, i.e., spindle. The results of this study is sufficient evidence that Korean strains were shown as the one of regional origin strain of domesticated silkworm such as the Chinese and Japanese etc.c.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제6권2호
• /
• pp.171-178
• /
• 2003

Four thermo-tolerant lines of silkworm, Bombyx mori, (L.) viz., A HT, B HT (Chinese type) and F HT, G HT (Japanese type) were evolved by utilizing the breeding resource material (identified from initial screening at a temperature of 31 ${\pm} 1^{\circ}C$ and relative humidity 85 ${\pm}$ 5%) through conventional breeding. These tolerant lines were crossed with productive breeds and forty four hybrids were evaluated on eight economic traits by the Multiple Trait Evaluation Index Method. Ten hybrids were short-listed based on the average evaluation index value larger than 50 for eight economic traits studied. The identified ten hybrids recorded higher index values (＞ 50) for most of the traits studied. Single hybrid G ${\times}$ CSR12 indicated average index value larger than 50 for six traits viz., pupation number (58), cocoon weight (67), shell weight (65), average filament length (74), raw silk % (69), reelability % (51) except for shell ratio % (41). The standard deviation of the cocoons in the above hybrid was 8.41 in the hybrid cocoon length and width measurement. However, two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 recorded average index value larger than 50 for all the traits viz., pupation number (57, 60), cocoon weight (50, 54), shell weight (56, 57), shell ratio percentage (59, 53), average filament length (55, 60), raw silk percentage (63, 67) and reelability percentage (53, 53). The standard deviation of the cocoons in the two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 was 8.41 and 8.06 respectively in the cocoon length and width measurement.