• International Journal of Industrial Entomology and Biomaterials
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• 제3권1호
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• pp.69-73
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• 2001

The effect of topical application 100,300 and 500 $\mu$g/ ml with Mineral Salts of magnesium sulphate and potassium nitrate on economic parameters was ana- lyzed following treatment of last larval stadium. The treated larvae showed significantly decreased larval weight and silk gland weight in all the treated groups along with other decreased Iarval, cocoon and adult parameters. The female cocoon weight was significantly decreased in all the treated groups with decreased female cocoon shell weight and male cocoon weight at 300 and 500$\mu$g/ml respectively. The length and weight of filament was significantly decreased at 300 and 500 $\mu$g/ml respectively and denier at 500 $\mu$g/ ml. The fecundity decreased significantly in 300 and 500 $\mu$g/ml treated groups when compared with the corresponding parameters of the carrier control.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권2호
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• pp.191-195
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• 2003

The impact of antibiotic (Norfloxacin) administration ,at different concentration (50 ppm and 100 ppm) on commercial characters of bivoltine $({CSR_2}{\times}{CR_4})$ and the cross breed race $({BL_67}{\times}{CSR_101})$ was studied. The result indicated that antibiotic administration with different concentrations significantly improved the rearing and cocoon parameters like larval duration, larval weight, growth index, single cocoon weight, single shell weight and shell ratio. The post cocoon parameters like average filament length, non-breakable filament length, raw silk percentage, raw silk recovery percentage, denier, reelability and neatness were recorded significantly higher in antibiotic treated batches. The better performances of these parameters were recorded with the increase of antibiotic concentration.

• International Journal of Industrial Entomology and Biomaterials
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• 제1권1호
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• pp.41-45
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• 2000

The effect of topical application with hydrocortisone on economic parameters was analysed following treatment of last larval stadium. The treated larvae showed a significant increase in larval weight at higher concentrations along with other enhanced larval, cocoon and adult parameters. This suggests that hydrocortisone can be used effectively for commercial silkworm rearing. The larvas period was significantly increased in all the treated groups with increased female cocoon weights, its shell weights and male cocoon shell weight at 20$\mu\textrm{g}$/ml treated group. Filament length, weight and denier were increased significantly in all the treated groups. Moth emergence percentage, length of the ovariole, eggs per ovariole, fecundity and rind hatching percentage were unaffected when compared with that of the carrier control group. This suggests that hydrocortisone in addition to affecting larval growths also affect silk crop.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권1호
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• pp.79-82
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• 2003

To study the effect of mounting fully ripe and unripe silkworms at different maturation percentage, the ripe and unripe silkworms were mounted separately and observed the cocoon and reeling characters. The significant difference in the cocoon and reeling parameters was observed between all ripe and unripe batches except for summer season. The silkworms collecting together and mounting at a time can be recommended only in summer season and at certain level during rainy season.

• International Journal of Industrial Entomology and Biomaterials
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• 제26권1호
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• pp.1-12
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• 2013

The commercial rearing of polyphagous Indian tasar silkworm, Antheraea mylitta Drury being practiced on naturally grown primary food plants like Terminalia arjuna, (Arjun) Terminalia tomentosa (Asan), and Shorea robusta (Sal) available in the tropical forests of central India, at times, is seriously affected by the disease- Pebrine, caused by Nosema sp., a microsporidian pathogen. The present investigation on comparative larval, silk gland weight and also cocoon parameters in Pebrine-free and Pebrine-infected ecorace of tasar silkworm Antheraea mylitta Drury (Daba TV), illustrates the tasar silkworm larvae infected with pebrine disease causing heavy losses to the economy of the silk industry.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.183-190
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• 2003

An attempt was made to identify superior bivoltine silkworm hybrid suitable for monsoon and spring season of Uttar Pradesh. Breeds with superior cocoon characters and their more popularity in an area were major parameters on basis of which breeds from different regions were selected. Six bivoltine hybrids of silkworm (Bombyx mori L.) of different geographical regions were reared in monsoon (three hybrids) and spring season (three hybrids) during 2000-2002 i.e., for three years at Babasaheb Bhimrao Ambedkar University, Lucknow. Their performances were analyzed statistically for nine characters. The analysis made on a number of traits viz., hatching percentage, larval duration, pupation rate, yield /10000 larvae (by no.), yield /10000 larvae (by weight), cocoon weight, cocoon shell weight, cocoon shell ratio, showed the superiority of one bivoltine hybrid out of the three bivoltine hybrids studied in each season. $SH6{\times}{NB_4}{D_2}$ was found to be superior in major cocoon parameters in both the seasons i.e., monsoon and spring season of Uttar Pradesh.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권1호
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• pp.75-78
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• 2005

Inheritance of cocoon and shell weight characters in silkworm crosses between sex-limited at larva stage lines, including three (NIG$_{1}$ $\times$ TV$_{3/2}$ ,NIG$_{1}$ $\times$ TBV$_{2/24}$ and NIG$_{1}$ $\times$ B$_{2/6}$ ) from Japanese type and three (NIG$_{2}$ $\times$ B$_{2/6}$ ,TV$_{3/2}$ $\times$ NIG$_{1}$ and NIG$_{2}$ $\times$ TBV$_{2/24}$ ) from Chinese type was studied at Regional Centre for Scientific­Applied Service - Vratza during the period of 2000 ­2002. Inheritance of tested characters in F I was deter­mined through genetic parameters, additiveness (a), dominance (d) and their ratio (d/a). Degree and frequency of transgressions in F$_{2}$ were calculated also. Over dominance (d/a(>) 1) with bigger contribution of the parent with higher value was determined at inheritance tested characters. Transgressions obtained at cocoon and shell weight characters were positive and varied in wide limits. The productivity of parent's lines had defined the variability of genetic parameters for degree and frequency of transgressions. Combination of positive transgressions at cocoon and shell weight characters in F2 hybrid populations from sex-limited at larva stage allow us to select individuals with high productive potential for further use in selection programs.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권1호
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• pp.59-63
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• 2003

In the present study, hybrid vigour in terms of heterosis and over dominance of newly evolved bivoltine hybrids and their reciprocals raised from the promising newly evolved bivoltine breeds were calculated for the important parameters like pupation, cocoon yield, cocoon weight, shell weight, shell ratio, raw silk percentage, filament length and neatness. Through there was no significant difference among the hybrids for the characters pupation, cocoon yield and cocoon weight, the magnitude of heterosis and over dominance were varied significantly for these characters. However, significant differences were observed between new hybrids and control hybrid for the characters like cocoon shell weight, cocoon shell ratio, filament length and raw silk percentage. The results indicate that majority of new hybrids have shown higher heterosis and over dominance than control hybrid. The data also indicate that highest mean heterosis of all new hybrids was recorded for cocoon yield followed by filament length. Whereas highest mean over dominance was recorded for cocoon yield followed by cocoon weight. Negative mean heterosis and over dominance were recorded for the trait cocoon shell ratio. Based on the results, the importance of three hybrids viz., CSR2 ${\times}$ CSR4, CSR2 ${\times}$ CSR5 and CSR3 ${\times}$ CSR6 and their reciprocals (CSR4 ${\times}$ CSR2, CSR5 ${\times}$ CSR2 and CSR6 ${\times}$ CSR3) which exhibited significant heterosis and over dominance, for commercial exploitation was discussed.

• 한국잠사곤충학회지
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• 제31권2호
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• pp.91-101
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• 1989

가잠육종의 선발에 대한 유전적 Parameter를 추적학 ldnl해 누에 일본종계통 3, 중국종계통 4 모두 7개 품종을 이면교배하여 주요 견성과 사질의 유전력과 유전상관을, 그리고 유전상관의 값을 이용하여 여러 형질이 직접 또는 간접적으로 견사량에 미치는 영향을 구명하기 위한 경로계수를 추정하였다. 원잠종을 재료로 한 각 형질의 유전력은 F1, F2세대에서 5령경과, 단견중, 견층중, 견층비율, fibroin량, 견층연감율, 견사량 등이 모두 76.65% 이상이었다. 형질상호간의 상관관계를 F1, F2 세대에서 자웅별로 보면 표현형상관과 유전상관의 값은 대체로 정의 방향이었고, 유전상관의 값이 표현형상관의 값보다 일반적으로 높았다. 견사량과의 형질상호간의 상관관계에서 단견중, 견층중, 견층비율, fibroin량 등은 F1, F2세대의 자웅이 모두 0.727 이상의 높은 유전상관 값을 보였다. 주요 형질들의 유전력이 대체로 높고 유전상관의 값이 정의 방향이므로 이들 형질은 선발이 용이할 것으로 기대된다. 경로계수는 견사량에 관여하는 직접효과가 F1세대에서 자의 견층중이 0.991, 웅의 단견중이 0.803이고, F2세대에서 웅의 견층비율이 0.938, 웅의 fibroin량이 0.930으로서 정의 방향으로 그 효과가 크게 표현되었다. 경로계수에서 견사량에 관여하는 직·간접효과가 세대간과 자웅간에 차이는 있으나 주로 증량적 형질인 단견중, 견층중 등의 영향이 컸을 것으로 평가된다.

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