• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.124-129
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• 1996

Oral application of dimethyl sulfoxide in different concentration (1, 3 and 5 percent) to silkworm, Bomyx mori at the fourth and the fifth instar has significantly increased the commercial characters such as larval and silkgland weights, female and male cocoon weights, their shell weights and egg production. However, larval duration, cocooning and hatching percentages did not showed any significant change, as compared with that of the corresponding parameters of the carrier control. Similarly the glycogen and protein contents of the fat body and trehalose and protein contents of the haemolymph were significantly increased in 1 and 3 percent, whereas the increase of them in 5 percent concentration did not take place significantly, except haemolymph trehalose where it was found to be significant, as compared with that of carrier control.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.118-123
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• 1996

Dietary supplementation of folic acid to silkworm larvae in different concentration (100, 200 and 300 ${\mu}$g/ml) to the 4th and the 5th instar resulted in a significant increase in economic parameters, such as female and male cocoon weights, shell weights, egg productivity and egg hatching percentage. However, larval duration was significantly decreased, as compared with that of carrier control. The increase in the glycogen and protein contents of the fat body was not significant, whereas the increase in trehalose content of haemolymph in all the treated groups and protein content of fat body and haemolymph in 100 ${\mu}$g/ml treated groups were significant. However, the haemolymph protein was significantly decreased in 300${\mu}$g/ml treated group.

• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.169-172
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• 2008

Indian tropical tasar silkworm, Antheraea mylitta D is reported to have forty four ecoraces by way of their adoption to different topographical and vegetational conditions. Of late, another ecorace 'JATA' - univoltine under in-situ condition has been explored which is localized in Thakurmunda area of the foot hills of Simlipal biosphere (Mayurbhanj district) of Orissa, India. The ecorace 'Jata' exhibits superior economic characters over widely commercialized ecoraces of Daba and Sukinda. The cocoon production of localized 'Jata' ecorace is depleting day by day in in-situ condition. In the present study, efforts were made to stabilize the ecorace 'Jata' under ex-situ condition at Ranchi (Jharkhand), where the 'Jata' ecorace silkworms were reared on Terminalia tomentosa for four successive generations during 2006 and 2007 and the cocoons were preserved in grainage house under prevailing climatic conditions. The results indicated change in voltinism behaviour of the 'Jata' ecorace from univoltine to bivoltine. The rearing performance and grainage efficiencies indicate the tendency of 'Jata' ecorace towards acclimatization and stabilization under Ranchi climatic conditions. The 'Jata' ecorace manifests the prospects for acclimatization, stabilization and commercial exploitation.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.21-23
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• 2011

In order to produce the colored cocoons we finalized the adequate amount of dyes throughout several trial and error experiments. The proper amount of each dye required for per 100 g of each colored cocoon turned out to be 150 mg of Rhodamine, 1560 mg of Thionin, 170 mg of Neutral red, and 200 mg of N-Blue, respectively. With this amount of dyes silkworms grew without physiological disorders. In order to produce colored cocoons, artificial diet composed mainly of mulberry leaves was fed to silkworms from the beginning of 5th instar, and subsequently fed with dye included diet from $4^{th}$ day of the 5th instar. This process resultantly produced colored silkworm body from the onset of feeding and subsequently colored cocoons and eggs. Nevertheless, the dye induced color was not inherited to next generation.

• International Journal of Industrial Entomology and Biomaterials
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• v.46 no.1
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• pp.9-15
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• 2023

Recently, a silkworm strain (tentatively named Sericinjam) producing 100% sericin cocoons has been studied in South Korea. In this preliminary study, the crystallinity, mechanical properties, and dissolution conditions of sericin from Sericinjam cocoons were examined. The Sericinjam cocoon could be dissolved in water at high temperature (120℃) and high pressure (HTHP method) in an autoclave and in a CaCl₂/H₂O/EtOH mixture (ternary solvent method), resulting in 82% and 97% dissolution after 30 min, respectively. The solution viscosity of the silk sericin formic acid (SSFA) solution obtained from sericin extracted using the ternary solvent method was higher than that obtained using the HTHP method; however, SSFA solutions obtained from sericin extracted from conventional Baekokjam cocoons yielded a higher solution viscosity. The crystallinity and breaking strength of the sericin film from Sericinjam cocoons were slightly lower, respectively, than those from Baekokjam cocoons. In contrast, the elongation at break of the Sericinjam sericin film obtained using the HTHP method was higher than that of the Baekokjam sericin film.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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• pp.189-194
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• 2004

Amylase isozyme based three multivoltine viz., N+p, Np, N+ $p^{cho}$ and two bivoltine-D6+p, D6p syngenic lines (Syn. L) were developed from germplasm (GP) stocks Nistari (N) and D6 respectively. haemolymph isozyme pattern at pH 7.0 and 8.5 depicted a total 11 number (Am $y_{1 to 6}$ at pH 7.0 and Am $y^{l to 5}$ at pH 8.5) of native proteins (NP) of various sizes are amylase isozyme expressers. Among eleven NPs, two NPs of 770 kDa (Am $y^{6}$ at pH 7.0) and 376 kDa (Am $y^3$ at pH 8.5) are $\alpha$-amylase expressers and remaining NPs of 370, 364, 350, 329 and 274 kDa at pH 7.0 and 206, 292, 416, 725 kDa at pH 8.5 are $\beta$-amylase expressers. Accordingly, digestive juice amylase isozyme pattern at aforesaid pH also depicted a total number of 10 NPs (Am $y^{1 to 5}$) at each pH 7.0 and 8.5 are amylase expressers of which NP of 387 kDa (Am $y^4$ at pH 7.0) and 780 kDa (Am $y^{5}$ at pH 8.5) are a-amylase expresser. Remaining NPs of 338,297 ＆ 216 kDa at pH 7.0 and 370, 341, 329 ＆302 kDa at pH 8.5 are $\beta$-amylase expresser. Recurrent backcross lines (RBL) viz., N+pRBL and NpRBL were developed through introgression of high shell weight character (a multigenic trait) to be used further for congenic line (Con. L) development and to understand any association with introgressed character. Isozyme pattern in haemolymph of RBLs depicted only one $\alpha$-amylase of 770 kDa at pH 7.0 and 376 kDa at pH 8.0 with three and four respective $\beta$-amylase bands but in bivoltine lines numbers of $\beta$-amylase bands vary between 1 to 2 at aforesaid pH. Variability was also observed in digestive juice of multivolitine and its RBLs but bivoltine lines express null activity at both pH except appearance of one very week $\alpha$-amylase band D6+p at pH 8.5. Overall study suggests that not a single NP at both pH is common for expression of any band of amylase isozyme i.e., a totally different set of proteins are the amylase isozyme expresser at specific pH and no molecular factor of amylase is associated in developed RBLs which showed improvement on survival, single cocoon shell weight (SCSW) and single filament length over receptor parents.s.s.s.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.133-139
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• 1974

The objective of this study is to compare the effects of raw materials as method of speeding up mounting of matured silkworm, for reducing concentrated labor during mounting periods. The results obtained from this study are summarized as fellows： (1) Quercus acutissima Carrs showed the most remarkable effect of repellent. Persicaria blumei Gross and Artemisia asiatica Nakai were followed in order. The rest repellents were also expected to be applicable. considering known material (silk-up) with lower mounting percentage. (2) The effective methods of preparation of repellent were to make distillate. Decocted solution type was considered to be the easiest way of preparation. (3) It seemed to be that there was little effect of repellent on the qualities of cocoon and silk. (4) When a repellent was applied to a silkworm bed, immatured silkworms were observed to mount. Thus it suggests that the repellent will give remarkable effects only when the degree of matured of silkworms is uniform.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.221-229
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• 2003

Ten multivoltine female parental lines were crossed with popular bivoltine male silkworm breed NB$_4$D$_2$. Three types of heterosis parameters viz., heterosis over mid-parental value (hybrid vigour), heterobeltiosis (useful heterosis) and standard heterosis (standard check) were estimated for 15 economically important quantitative traits. The interaction among the hybrids and parents indicated significant effect for maximum characters. The heterotic effect of new hybrid combination was compared with popular hybrids viz., Pure Mysore${\times}$NB$_4$D$_2$ and Nistari${\times}$NB$_4$D$_2$. Varied heterotic effect was observed for different traits for different hybrid combination. The results inferred that the crosses viz., BL$_{23}$${\times}$NB$_4$D$_2$ ranked top for 14 traits followed by Hosa Mysore${\times}$NB$_4$D$_2$ for 11 traits; PA$_{12}$${\times}$NB$_4$D$_2$ for 9 traits; BL$_{24}$${\times}$NB$_4$D$_2$ for 8 traits; Kolar Gold${\times}$NB$_4$D$_2$ for 7 traits; WAI$_1$${\times}$NB$_4$D$_2$ for 6 traits and MU$_{11}$${\times}$NB$_4$D$_2$ for 5 traits. Among these, the best hybrids Kolar Gold${\times}$NB$_4$D$_2$ and MU$_{11}$${\times}$NB$_4$D$_2$ were identified for longer filament length and fine denier. Similarly for higher cocoon yield and silk productivity BL$_{223}$${\times}$NB$_4$D$_2$ and BL$_{24}$${\times}$NB$_4$D$_2$ were found to be superior. These hybrid combinations are suitable for commercial exploitation at large scale.e.e.e.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.51-62
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• 1968

This study was carried out to investigate the life cycle and the damage of Tricholyga sorbillans Wiedmann to silkworms(Bombyx mori L.). The results are summarized as follows. 1. This insect has 5 or 6 generations per year in Suwon area. 2. The egg, larval, and pupal stage are about 2, 8 and 18 days respectively. 3. The weather conditions considerably affect the life cycle, that is, the 3 rd generation is the shortest of all, lasting for 21 days and l4 hours, and the 5th generation is the longest for about 40 days. 4. The larvae come out of silkworm bodies, burrowing into the ground 3.5cm to 10.5cm in depth before changing into the pupae. 5. This insect does not overwinter as pupa, but seems to do as larva, parasiting on the field insects. 6. The damage of Tricholyga sorbillans Wiedmann to silkworm was 27.9％, it is so high that the silk worms could not be reared outside without a reasonable control method. 7. When the full-grown silkworm is parasited by one egg of these insects, there is not only enough possibility of spinning. but also without any effects of their larvae on the cocoon quality. 8. The damage of Tricholyga sorbillans Wiedmann throughout the country covers 6.36％ in spring, 4.09％ in fall, and 5.25％ yearly mean.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.2
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• pp.39-44
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• 2011

To evaluate the growth rate of larval and pupal parameters of silkworm Bombyx mori fed with Silver Nanoparticles (AgNps) treated $MR_2$ mulberry leaves, the following works have been considered. The AgNp was synthesized by chemical reduction method, it was diluted by different concentrations such as 25%, 50%, 75% and 100% (without dilution). Fresh mulberry leaves (Morus alba L.) were sprayed by each concentration and were fed to silkworms, from $3^{rd}$, $4^{th}$ and $5^{th}$ instar, five feedings/day. Group $T_1$ larvae received $MR_2$ mulberry leaves sprayed with distilled water and served as control, group $T_2$, $T_3$, $T_4$ and $T_5$ larvae received 25%, 50%, 75% and 100% AgNps sprayed mulberry leaves, respectively. Silkworm larvae fed on M. alba ($MR_2$) leaves sprayed with 25% concentration of AgNps (group $T_2$) was significantly increased the larvae and cocoon length, width and weight as compared to those fed on control (group $T_1$) $MR_2$ mulberry leaves and other groups ($T_3$, $T_4$ and $T_5$). Hence, 25% AgNps dose was fixed as an effective dose. It has been observed from the present study that 25% AgNps treated (group $T_2$) leaves fed by silkworms have enhanced the larval and pupal growth and quantity of silk production than control.