• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.1-13
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• 2004

Indian multivoltine mulberry silkworm (Bombyx mori L.) strains are poor in silk productivity and fibre quality. However, they are commercially exploited for the past five decades either in the form of pure breeds or cross breeds because of their adaptability to adverse climatic condition and acclimatization to specific regions and seasons. In the present paper conservation strategies of multivoltine silkworm genetic resources are dealt along with detailed information on accessibility of genetic resources, method of genetic resources conservation, characterization of genetic resources for morphological and productivity traits of economic importance. Selection of best ten accessions based on various economic parameters including yarn quality and their scope for future utilization are discussed.

• 한국잠사곤충학회지
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• 제5권
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• pp.19-23
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• 1965

가잠을 이중교배함으로씨 발생하는 형질을 조사한 결과 다음 결과를 얻었다. 1. 10분간 이중교배한 결과 그 형질이 잠품종에 따라 변화하였다. 그러므로 잠종제조에 있어서 자유교미를 절대적으로 방지하여야 한다. 2. 동품종과 이품종간의 수정력강도에 일정한 경향을 발견하기가 곤란하다. 그리고 먼저 사정된 정자가 뒤에 사정된 정자보다 우위를 차지한다고 보기 곤란하다.

• International Journal of Industrial Entomology and Biomaterials
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• 제3권2호
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• pp.109-112
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• 2001

Androgenesis in silkworm acquires a special significance as along with combined applications of other breeding strategies like parthenogenesis and cloning, it may serve as n valuable tool for sex control in sericulture as well as selection and production of bisexual homozygous androgenetic lines. Production of hybrid silkworm yielding high proportion of male larvae is of immense use to silk industry (Strunnikov, 1975, 1983). In this review, an attempt has been made to assimilate the works carried out on androgenesis, different techniques of induction towards androgenetic development and its role in silkworm breeding.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권1호
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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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• 제8권1호
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• pp.117-121
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• 2004

Soluble proteins of silkworm hemolymph were investigated by means of isoelectric focusing (IEF). The protein spectra during ontogenesis of races and inter-races hybrids kept in Bulgaria was studied. A total of 51 protein bands in the hemolymph from fourth larval instar to imago were ascertained. Stage specific expression was established. The specific expression of some protein bands in the individual spectra manifest phenotype of gene determinate polymorphism (HP F, HP J, HP K, HP L, HP Q - in the zone with pH gradient 3.5-6.2 and HP K, HP L, HP N, HP P, HP T - in the zone with pH gradient 9.5 - 6.2). Breed specific expression was observed. On the basis of the obtained results, it was established that the investigated breeds are heterogeneous and the isoelectric focusing method is successful when specifying the inner-race and inter-race polymorphism in silkworm.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권1호
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• pp.37-44
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• 2007

A study was made of the haemolymph protein spectrum of mulberry silkworm (Bomhyx mori L.) from the first larval instar to imago. Horizontal starch gel electrophoresis was used. Sixteen races and eight F1 interracial hybrids, raised in Bulgaria, were analyzed. During the ontogenesis, a total of 17 protein bands (15 cathodic and 2 anodic) were detected. Distinct dynamics in the haemolymph protein spectrum was observed, in result of different expression during the individual development associated with the processes of growth, histolysis and histogenesis. Based on the ontogenetic dynamics found, a correspondence was assumed between some proteins detected by us using the starch gel electrophoresis and major haemolymph proteins (SP1, SP2, MHPs and Vg) detected by other authors using the polyacrilamide gel electrophoresis. Intraracial and interracial polymorphism was observed in four protein zones. The effect of four polymorphic loci with codominant and null alleles was suggested.

• 한국잠사곤충학회지
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• 제37권2호
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• pp.121-126
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• 1995

1000배로 희석한 "인세가"9주성분 : fenoxycarb)를 분무한 뽕잎을 일정기간 누에에 섭식시킨후 각 령의 경과일수, 5령 유충무게, 화용비율, 전견중 및 견층중 등에 미치는 영향을 조사하여 다음과 같은 결과를 얻었다. 1. fenoxycarb 첨식은 유충경과 일수를 연장시킨다. 특히 4령 3일 이후의 처리에서는 5령 경과일수가 20일 이상 길어지고 토사하지 못한채 모두 폐사하였다. 2. fenoxycarb 첨식은 5령 유충무게를 증가시킨다. 처리구의 유충무게 최대치는 대조구에 비해 2령 전기간 처리구에서 약 20%, 3령, 4령, 5령기의 전기간 처리구에서 각각 40%, 70%, 20% 정도 증가하였다. 3. 화용비율은 1령 처리구에서는 90% 이상으로 대조와 큰 차이는 없었으나 2~3령 처리구에서는 70~8-0%, 4령 후반기 이후 처리구에서는 0%였다. 4. 전견중 및 견층중은 1~3령 처리구에서 대체로 증가하였고 특히 전견중은 2령 전령 처리구에서 대조대비 47% 견층중은 3령 전기간 처리구에서 41% 증가하였다.41% 증가하였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권2호
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• pp.149-153
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• 2002

Induction of non-diapause eggs and manifestation of quantitative characters were studied in different seasons by low temperature incubation of eggs of a low yielding diapause with coloured cocoons silkworm breed, RDI of Bombyx mori. Hundred percent of nandiapause eggs were induced when the egg incubation was carried out at 15$^{\circ}C$ followed by incubation initially at $25^{\circ}C$ and then at $15^{\circ}C$. The diapause-nondia-pause relation was found to be reversible. Analysis of variance study demonstrated significant variation in all the quantitative characters whereas significant variation due to different incubation treatments was observed for larval span, fifth instar larval span, cocoon yield/10,000 larvae by weight, cocoon weight, cocoon shell weight, and cocoon shell ratio. study on hybrid vigour skewed significant heterosis over mid parent value for four economic characters viz., cocoon weight, cocoon shell weight, cocoon shell ratio and filament length in a Fl hybrid between RD1 with diapause eggs and Japanese type bivoltine $NB_{4} D_{2}$.

• International Journal of Industrial Entomology and Biomaterials
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• 제13권2호
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• pp.63-72
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• 2006

Parthenogenesis, the development of unfertilized ovum opens new perspectives in silkworm breeding in the development of homozygous breeds. In order to improve induction of artificial parthenogenesis in the excised unfertilized eggs of different breeds of the silkworm, Bombyx mori L., a new method was devised and the results were compared with the routine method. General and specific combining abilities and hybrid vigour of newly developed bivoltine breeds were analyzed utilizing bivoltine breeds viz., $CSR_2,\;CSR_4,\;CSR_{17}\;and\;NB_4D_2$ Estimation of GCA revealed superiority of the breeds, $DNB_1$ for eight characters followed by $DNB_4$ for five characters. Among the testers, $CSR_2$ was found good general combiner for seven characters followed by $CSR_{17}$ for four characters. A great deal of variations was observed among the hybrids studied. Five hybrids namely, $DNB_1{\times}CSR_2,\;DNB_4{\times}CSR_4,\;DNB_4{\times}NB_4D_2,\;DNB_6{\times}CSR_2\;and\;DNB_7{\times}CSR_2$ showed significant SCA effects for 5-6 characters. The hybrid, $DNB_4{\times}CSR_4$ showed its superiority by expressing significant hybrid vigour over BPV for 7 characters. Majority of the hybrids exhibited significant hybrid vigour for survival rate, yield/10,000 larvae by weight, cocoon weight, cocoon shell weight, filament length and denier.

• International Journal of Industrial Entomology and Biomaterials
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• 제5권2호
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• pp.189-194
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• 2002

Silkworm diseases are major constraint in silk cocoon production. Among silkworm diseases, white muscar-dine is highly contagious and most common in winter and rainy seasons. It is suggested that hemocytes involve in defense against invasion of Beauveria bassi-ana and systemic fungicide/chemicals prevent the proliferation of fungi in the hemolymph or preventing the growth of the fungi in the body cavity through enhancing the hemocyte mediated defense response. In the present study the influence of systemic fungicide on hematological changes in silkworms infected with Beauveria bassiana was reported. It is observed that the total hemocyte counts increased in the hemolymph up to 5 days post inoculation in systemic fungicide treated batches while in the inoculated control the increase was up to 3 days indicating the positive hemocyte mediated response in silkworm treated with systemic fungicide. After 2 days in the inoculated control as the multiplication and growth of mycelia increased, defense capacity of the silkworm was decreased. The biochemical changes were also observed in the hemolymph of silkworm infected with B. bassiana. In silkworm infected with Beauveria bassi-ana, the total protein content increased whereas total carbohydrate and total lipids decreased as the infection progresses. In the case of systemic fungicide treated batches the increase in total protein content was comparatively higher and decrease in total carbohydrate and lipids were comparatively lower than the inoculated control.