• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.47-52
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• 2000

The effect of supplementation with potassium nitrate on economic parameters was analysed following treatment of last larval stadium. The treated larvae showed a significant increase in larval weight at 500$\mu\textrm{g}$/ml and silk gland weight in all the treated groups along with other enhanced larval, cocoon and adult parameters. The larval period was significantly decreased in all the treated groups with increased female and male cocoon weights its shell weights filament lengths at 500$\mu\textrm{g}$/ml. The denier was significantly decreased in all the groups. The filament weight moth emergence percentaged length of the ovariole were unaffected. However, eggs per ovariole, fecundity and hatching percentage significantly decreased compared with the corresponding parameters of the carrier control.

• Journal of Sericultural and Entomological Science
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• v.22 no.2
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• pp.1-7
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• 1981

Diallel crosses among six silkworm varieties were used as the materials by the randomized block design. and combining ability tests were conducted to determine the relationships between parents and their F$_1$ hybrids. The six parents and their 30 F$_1$ crosses were evaluated for five quantitative characters in each female and male silkworms. Mean values of period(days) of larval stage in mid-parent were more than those of each F$_1$ hybrids. Highly significant differences were shown in the total cocoon weight and weight of cocoon layer of silkworms in F$_1$ hybrids of 111$\times$114, 111$\times$ yunil, 114$\times$yunil and those of reciprocal crosses. From the results, it was recognized that varieties A(111), D(114) and F(yunil) were useful varieties as the parents in breeding of silkworms for increasing the total cocoon weight and weight of cocoon layer, etc. Differences among crosses in apparent degree of heterosis existed for total cocoon weight of cocoon layer and cocoon layer ratio, etc. Mean square values of GCA (general combining ability) were more greater than those of SCA(specific combining ability) for period(days) of larval stage, period (days) of 5th instar and cocoon layer ratio of silkworms. The effects of GCA were differ from parents and characters and the effects of SCA were also differ from parents, characters and crosses.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.1
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• pp.45-50
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• 2007

Ethanol extract of 20 botanicals in 3 concentrations i.e., 2.5%, 5% and 10% were evaluated for their efficacy to improve reproductive performance of mulberry silkworm (Bombyx mod L.) through feeding botanical enriched mulberry leaves during $2^{nd}$ day of $4^{th}$ age as well as $1^{st}$ and $3^{rd}$ day of $5^{th}$ age larvae. The preliminary screening was done by ranking the botanicals based on influence in most important reproductive contributing parameters such as single cocoon weight, effective rate of rearing, pupation rate, fecundity and recovery of eggs/kg cocoon. Five botanicals viz., Asparagus recemosus, Achyranthes aspera, Tribulus terrestris, Withania somnifera, Parthenium histerophorus ranked first were further evaluated at 8% 5% and 3% concentrations to confirm their effectiveness and standardize effective concentration. Among the rearing parameters, mature larval weight, shell ratio and number of cocoons/kg were not significantly influenced by the treatments. However, reproductive parameters such as effective rate of rearing (wt), pupation rate (%), fecundity (No.) and egg recovery (g)/kg cocoon were significantly (P<0.05) influenced by the botanicals. Higher fecundity and egg recovery were obtained on treatment with Withania somnifera irrespective of concentrations. However at 5% concentration, pupation rate, fecundity as well as egg recovery were found significantly higher than that of other concentrations, confirming its effectiveness for improving reproductive efficiency.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.2
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• pp.85-95
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• 2006

Seveval Chinese and Japanese varieties with good characters were used in the breeding. After 5 years (15 generations), a pair of robust and high quality silkworm variety with NPV resistance was bred by means of a combination of crossing and pedigree selection complemented by the selection of NPV resistance. The variety was identified jointly nationwide in 2003 and 2004, and appraised by National Mulberry and Silkworm Appraising Committee. Results are as follows: its cocooning rate is over 93%, shell rate 23-25%, filament length 1200-1300 meters, reelability 75-88%, Length of non-broken cocoon filament 900-1100 meters, raw silk rate 17-19%, neatness 95-97 points, and cocoon crop, cocoon shell weight and raw silk weight per 10000 larvae is higher than those of the control variety by 7-10%, 14-19% and 14-18%, respectively. The variety is not only robust, resistant to high temperature and NPV, easy to rear, uniform in hatching, molting and maturing, but also lays more eggs, and its fecundity is high. It is suitable to rear in the Yangtze River Basin, the Yellow River basin and the Pearl River basin of China.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.1004-1009
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• 2001

Acid hydrolysates of cocoon was gained by acid hydrolysis of 2 N HCl, 11$0^{\circ}C$, 48 hours, neutralization and desalting from the cocoon. The amino acid compositions of acid hydrolysates of cocoon were glycine 43.25%, alanine 34.39%, serine 10.05% and valine 2.44%. The contents of essential amino acid was 10.05%. Food efficiency ratio of acid hydrolysates of cocoon group was equal to the reference protein, casein. Liver weight, GOT, GPT activity, serum albumin and serum total protein level of rats were not significantly different among the experimental groups. Therefore, the protein acid hydrolysates of cocoon is not of high quality. When the rat fed with high cholesterol, high lipid, and high sucrose diet was administered with 5% acid hydrolysates of cocoon, its plasma lipids concentration of acid hydrolysates of cocoon was favorably affected: its triglyceride was decreased, and the level of phospholipid and HDL cholesterol were increased. There was also an unfavorable effect: the levels of LDL cholesterol and total cholesterol went up. Therefore, the acid hydrolysates of cocoon is not a good protein food source, but is can be used a cosmetic, medical, or packing material. Further research will reveal how it will affect or improve plasma lipid.

• International Journal of Industrial Entomology and Biomaterials
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• v.47 no.1
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• pp.63-71
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• 2023

In this study, the structural characteristics of sericin recovered from wastewater released from the silk textile industry (Plant sericin) were comparatively analyzed with those of sericin extracted from a silkworm cocoon produced in a laboratory (Lab sericin). To prepare Plant sericin, ethanol was added to wastewater (i.e., a sericin aqueous solution) after the degumming process to remove nonprotein materials, affording a sericin precipitate. To prepare Lab sericin, nonprotein materials were removed from a silkworm cocoon and sericin was subsequently extracted from the cocoon. Lab sericin and Plant sericin exhibited similar solution viscosities, gel strengths, and crystallinity indices, indicative of the similar molecular weights (MWs) of the two sericin samples. In the case of sericin powder, Plant sericin was more crystalline than Lab sericin due to its treatment with ethanol. The findings of this study revealed that sericin recovered from industrial wastewater can be used equally as its MW is similar to that of sericin obtained through laboratory-scale extraction.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.111-115
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• 2004

Nutrition plays an important role in maintaining the larval health, cocoon quality and reproductive potential in Antheraea mylitta D. Nutritional efficiency greatly influenced if food is not adequate and of quality. A. mylitta silkworms were subjected to food deprivation for the period of 0 hr to 12 hrs /day to assess its effect on various nutritional parameters and indices, and its manifestation at different levels. Food ingesta, digesta, gain in body weight declined significantly at each level of deprivation, so also food utilization efficiency like consumption index (CI), growth rate (GR), approximate digestibility (AD), and efficiency of conversion of ingested food (ECI). This stress leads to decline in mean daily food ingesta by 16.73% to 39.76% and digesta by 28.98% to 54.01 % following a significant reduction in average daily body weight gain (27.68% to 55.09%). Food deprivation a1so caused significant loss in the silk gland weight, cocoon and shell weight (14.37% to 53.69%), lowered the fecundity (35.86 % to 83.59%) and in number of eggs laid per gram body weight, but simultaneously the number of non-chorionated eggs increased significantly.

• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.121-126
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• 1995

The effects of oral application of fenoxycarb, the commercial formulation Insegar, to the selected developmental stages of the silkworm, Bombyx mori, was investigated. An oral application of the chemical to the silkworm from the 2nd- to the 5th-instar larvae delayed the larval development upto more than 40 days and increased the larval body weight in the range of 1.1 to 1.7 folds. When the chemical was orally applied to the final instar larvae, spinning and pupation were prevented, and consequently permanent larvae occurred. The weight of a cocoon and its shell of silkworm(bombyx, mori, L) increased following the application of fenoxycarb to the 2nd- and the 3rd-instar larvae.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.113-116
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• 2001

Fifth instar larvae of the new bivoltine hybrid (CSR2 ${\times}$ CSR5) were reared under different temperature and humidity viz., $20^{\circ}C$ and 85 ${pm}$ 5% R.H (T1), $25^{\circ}C$ and 70 ${pm}$ 5% R.H (T2-Optimum), $30^{\circ}C$ and 80% ${pm}$ 5 R.H (T3) and $35^{\circ}C$and 50 ${pm}$ 5% R.H (T4). The cocoon yield, cocoon characters and disease incidence were studied in normal (non infectious source, i.e control) rearing as well as in 1% infectious source of rearing. The results indicated that V instar larval duration was prolonged and cocoon weight was improved in T1. ERR and shell ratio were significantly improved and disease incidence was minimised in T2. Further significant difference was observed among the treatments with regard to spread of diseases.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.1
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• pp.7-14
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• 2006

A breeding programme was initiated during 2001 to introduce sex-limited larval markings to a productive multivoltine breed - BL67 from an inbred sex-limited line, MY1 (SL) maintained at Central Sericultural Research and Training Institute, Mysore. Introgressive hybridization, recurrent backcrossing for six generations followed by sib-mating resulted in synthesis of a new multivoltine silkworm breed BL67 (SL) with sex-limited larval markings. The new breed was studied for combining ability by crossing with eight bivoltine breeds viz., $NB_4D_2,\;CSR_2,\;CSR_2 (SL),\;CSR_2,\;CSR_4,\;CSR_8,\;CSR_{18}\;and\;CSR_{19}$. General combining ability effects of the new breed showed its superiority over the popular Pure Mysore by expressing significant GCA effects for six out of twelve characters whereas the results are on par with the original multivoltine breed. The hybrid $BL67(SL){\times}CSR2(SL)$ excelled in several quantitative characters such as pupation rate (90.2%), cocoon weight (1.97 g), cocoon shell weight (40 cg), cocoon shell ratio (20.3%), filament length (918 m), denier (2.96), raw silk percentage (14.96%) and neatness (90 p). Studies on cocoon size variability revealed that the cocoons of $BL67(SL){\times}CSR2(SL)$ were found comparatively uniform showing less standard deviation of 6.55 and co-efficient of variation of 3.91 %. The suitability of newly developed breed for easy grain age operation and commercial exploitation with promising hybrid have been discussed.