• International Journal of Industrial Entomology and Biomaterials
• /
• v.5 no.1
• /
• pp.59-65
• /
• 2002

Parthenogenetic development, hybrid vigour and cocoon shape variability were studied in bivoltine F1 hybrids of the silkworm, Bombyx mori L. Considerable breed differences were observed in parthenogenetic ability. Among the parental breeds, CSR18 exhibited maximum parthenogenetic development (79.65%) followed by CSR4 (67.90%). Among bivoltine F1 hybrids, CSR18 ${\times}$ CSR4 showed highest parthenogenetic development (73.32%) followed by CSR2 ${\times}$ CSR4 (55.43%). Study on hybrid vigour demonstrated that CSR18 ${\times}$ CSR19 expressed maximum significant hybrid vigour for all the seven economic characters over Mid Parent Value (MPV) followed by CSR2 ${\times}$ CSR4 and CSR18 ${\times}$ CSR4 exhibiting significant heterosis for six characters. Cocoon shape measurement study revealed that among ten bivoltine F1 hybrids, cocoons of three hybrids were found comparatively uniform. Importance of this study to know the level of paythenogenetic development, hybrid vigour and cocoon shape variability in different bivoltine F1 hybrids have been discussed.

• Journal of Sericultural and Entomological Science
• /
• v.38 no.2
• /
• pp.130-137
• /
• 1996

Effect of topical application with 5, 10 and 15${\mu}$g/ml thyroxine on the pre-cocoon, cocoon, postcocoon and silk improvement were studied in bivoltine silkworm NB18 breed of B. mori L. Thyroxine was applied independently on alternate days to silkworm of IV and V instar larvae. The treatment of all different concentrations resulted in a significant increase in commercial characters like larval weight, silkgland weight, cocooning percentage, female cocoon weight and its shell weight and male cocoon shell weight and its ratio, cocoon dimension, length of the filament and its weight and oviposition. However, there was no significant change in larvel weight in 5${\mu}$g/ml treated group and larval duration was significantly decrease. But moth emergence percentage and hatching percentage did not show any significant change when compared with that of carrier control.

• Journal of Sericultural and Entomological Science
• /
• v.14 no.2
• /
• pp.73-79
• /
• 1972

This study was carried out to investigate the effects of the mulberry leaves sprayed with filtered solutions and non-filtered solutions of ginseng, on the various practical characteristics of the silkworm (Bombyx mori) in spring, summer and late autumn in 1971, and spring and autumn in 1972. 1. There was no evidence that the various ginseng concentrations influence the practical characteristics in the silkworms, according to the different instars and rearing seasons. 2. Non-filtered solutions of ginseng have a bad effect upon the silkworm characteristics, especially in pupation ratio and reelable cocoon ratio.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.6 no.2
• /
• pp.191-196
• /
• 2003

Silkworm body and rearing seat disinfection is an integral part of effective silkworm rearing as it prevents the spread of various diseases through secondary contamination in the rearing bed. Many bed disinfectants are recommended by various research institutes in India. In the present study, eight bed disinfectants viz., Vijetha, Labex, Resham Jyothi, Sanjeevini, Suraksha, Reshamkeet Oushadh, Dithane M45 and Captan recommended by various Sericultural Research Institutions in the country against the spread of common diseases of silkworm were tested to determine their comparative efficacy. For the study, all the treatment batches were introduced with fixed number of specific diseased larvae so as to maintain a constant source of pathogen in the bed and then followed by treatment with respective bed disinfectants. Percent mortality/infection due to each disease was recorded to determine efficacy of bed disinfectant treatment against respective disease. The results show that all the bed disinfectants tested have considerable efficacy against the spread of various diseases in the rearing bed. However, Vijetha was distinctly superior in its efficacy against all four major diseases of silkworm. The study emphasize the role of bed disinfectants in silkworm rearing and the fact that they should be judiciously selected based on the efficacy of the bed disinfectant and the type of disease prevalent in a particular season and area.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.6 no.1
• /
• pp.27-31
• /
• 2003

Infectious flacherie of silkworm Bombyx mori is caused by B. mori infectious flacherie virus (BmIFV) and causes severe crop loss to sericulturists. In the present study, a colloidal textile dye-based dipstick immunoassay is developed for the detection of infectious flacherie in silkworms. Colloidal textile dye (blue D2R) with Aλ$_{max}$ at 620 nm was sensitised with 500 $\mu\textrm{g}$/ml of purified anti-BmIFV IgG. The dye-antibody reagent detects purified antigen up to 10 ng/ml and BmIFV infection in diseased larval extracts $(up to a dilution of {10^-5})$ and faecal matter extracts $(up to a dilution of {10^-2})$ by forming clear blue dot within 30 min. It was observed to be stable for three months period at $4^{\circ}C$. The efficacy of textile dye-based dipstick immunoassay was on pay with HRP-based dipstick immunoassay and fluorescent antibody test, and better than latex agglutination and ouchterlony tests in the detection of BmIFV The dye-based dipstick immunoassay method provides a simple, sensitive and less expensive test for the detection of BmIFV infection in silkworms.s.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.25 no.1
• /
• pp.111-114
• /
• 2012

In previous studies we have shown that a sw17255 gene was expressed in hemocyte-specific tissues of the silkworm, Bombyx mori L. (Lepidoptera: Bombycidae). It was verified that the sw17255 core promoter region contains elements that regulate the expression of this gene in hemocyte tissue; the selected promoter region spans nucleotides -1 to -2,112 upstream of the start codon. Each of the luciferase reporter gene expression vectors under the control of 4 different kinds of promoter candidates, (-2,112/-1), (-1,640/-1), (-1,169/-1) and (-579/-1), and the control reporter plasmid DNA, were introduced into B. mori larval coelom by direct injection using a syringe. The promoter candidate [E] (-579/-1) showed more than 1.67 fold transcriptional activity compared to control promoter activity. Higher productivity of an expressed gene in the transgenic silkworm by this promoter combination could be achieved in the near future. The foreign recombinant protein could be easily harvested from the blood of the transgenic silkworm.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.6 no.2
• /
• pp.207-210
• /
• 2003

Four different backcrossing methods were designed and 23 near isogenic lines (NILs) of 22 linkage groups were obtained using Hb as recurrent parent, the mutant gene lines which held markers as donor parents. Eleven of them had been mated with the recurrent parent for 10 times, and the others for 7∼8 times. The NILs of other 6 linkage groups are under way and had been backcrossed to the recurrent for 3∼4 times. These NILs will act important roles in the construction of molecular linkage map and gene location and positional cloning.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.9 no.2
• /
• pp.261-264
• /
• 2004

Kolar gold (PM${\times}$CSR2) is the most popular cross breed of India, especially in Karnataka. During January - February 2004 we observed several phenotypic variations leading to poor survival. Though occurrence of morphologically abnormal individuals is common, the extent of occurrence in the present report was on the higher side (upto 6 percent). It is unwarranted and not desirable in commercial silkworm rearing. The variations exhibited might be due to change in the environmental conditions like incubation temperature during embryonic stage or spontaneous mutation resulting out of environmental stress.

• Journal of Life Science
• /
• v.28 no.6
• /
• pp.697-707
• /
• 2018

The aim of this study was to investigate the potential effects of extracts from silkworm (Bombyx mori L.) that was fermented with Bacillus subtilis KACC 91157 at the levels of 1%(v/w), 2.5%(v/w), and 5%(v/w) in alcohol-fed rats. Sprague-Dawley rats were divided into seven groups: normal group (N), alcohol treated group (C), silymarin treated group (PC, positive control), 5% silkworm powder treated group (SP5), 1% Bacillus subtilis-fermented silkworm powder treated group (BSP1), 2.5% BSP treated group (BSP2.5), and 5% BSP treated group (BSP5). The activities of AST, ALT, ALP, and LDH in the serum and the triglyceride concentrations in the liver and serum were increased by alcohol feeding but were reduced in the BSP5 group. In addition, the contents of total lipids, free fatty acids, and total cholesterol were increased in the alcohol-fed group but were reduced in the BSP5 group. The activities of ADH, ALDH and ADH, ALDH protein levels in the liver were increased in the BSP5 group. The TBARS contents in the liver, serum, liver mitochondria, and liver microsomes were slightly decreased in the BSP5 group compared to the C group. The hepatocytes in alcohol-fed rats contained numerous large droplets; however, BSP5 treatment prevented alcohol-induced lipid droplet accumulation in the hepatocytes. Based on these results, extracts from Bacillus subtilis-fermented silkworm (Bombyx mori L.) have significant potential for development into a functional health food that can improve alcoholic fatty liver conditions.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.7 no.1
• /
• pp.5-10
• /
• 2003

The nuclear polyhedrosis virus (NPV) resistance of silkworm is controlled by a pair of dominant genes on autosome and micro-effect modificator genes on sex chromosome Z and has the phenomenon of patroclinal inheritance. Based on its hereditary characteristics, methods of preparing near isogenic lines and their $F_2$ populations for screening molecular markers were designed.