• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.107-113
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• 2003

Analysis of combining ability is a widely used biometrical tool to select promising parents and hybrids, to determine the kinds and relative magnitudes of genetic variability among hybrids as well as to forecast yield attributes in early breeding generations both in plants and animals. Various statistical approaches like Jinks and Hayman (1953), Griffing (1956), Kempthorne (1957) etc. have been extensively applied in plants. These approaches have also been tried in the mulberry silkworm, Bombyx mori L. In the present review, an attempt has been made to collect most of the studies carried out on combining ability in silkworm at one place and make it available to the scientists engaged in sericultural research.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.51-57
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• 2003

A cDNA encoding a putative alcohol dehydrogenase (ADH) class III was cloned from the silkworm, Bombyx mono The full length cDNA is 1,385 nucleotides long and contains an open reading frame of 1,128 bp encoding 376 amino acid residues. The B. mon ADH III protein sequence was aligned with ADH III known from various organisms. Interestingly, the protein sequence of B. mon ADH III showed 87% and 85% identity to ADH III from marine fish Sparus aurata and Branchiostoma floridae, respectively, whereas rather low sequence identity (83%) to Drosophila melanogaster ADH III was observed. Northern blot analysis revealed that B. mon ADH III mRNA is expressed in all tissues from larva examined: fat body, midgut, epidermis, silk gland and ovary, with the highest level found in the fat body.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.87-91
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• 2003

BmNPV (Bombyx mori nuclear polyhedrosis virus) causes nuclear polyhedrosis in silkworms. The tolerance of silkworms to BmNPV is controlled by polygenes. This paper reports on the relative tolerance of silkworm breeds among the germplasm maintained at Andhra Pradesh State Sericultural Research ＆ Development Institute (APSSRDI), Hindupur, India. The silkworm larvae out of second moult were per orally inoculated with BmNPV polyhedra $(l{\times}l0^{th}//ml)$ and reared upto spinning. The response to BmNPV had been categorized into apparent tolerance, real tolerance and susceptibility. Among the 145 silkworm breeds screened, 18 bivoltines and 16 polyvoltines were found to have real tolerance to BmNPV.

• Journal of Sericultural and Entomological Science
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• v.41 no.2
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• pp.87-93
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• 1999

Under Light and Scanning electron microscope, the pupal morphology of mulberry silkworm Bombyx mori Linn. revealed the prothorax and metathorax, well developed mesothorax, less defined last pair of sporacle, well exposed prothoracic femora and wing pads approaching the anterior margin of Ab III. The important sex separating characters viz, wegiht, antennal elevations, intersegmental lines and genings have discussed. Further, two separate openings bursa copulatrix and ovipositional opening were observed, performing different functions in abult moth.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.231-233
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• 2003

To understand the physical method for induction of anti-bacterial substances from the silkworm larvae, Bombyx mori, three physical methods, i.e., infrared radiation, ultraviolet radiation and ultrasonic wave, have been used in this study. The results have shown that ultrasonic wave can induce anti-bacterial sub-stances effectively than radiations in the B. mori larva. The induction of anti-bacterial substances was different from silkworm race to race. Summer-autumn silkworm race (Qiufeng${\times}$Baiyu) was easy to induce antibacterial substances. It is suggested that the ultrasonic wave is a simple and easy method for induction.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.2
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• pp.119-122
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• 2001

Whether Bombyx mori nuclear polyhedrosis virus (BmNPV) can be transmitted to offspring, has been a noticeable question for a long time. When fifth instar larvae of the silkworm were orally inoculated with BmNPV dot hybridization and PCR amplification analysis demonstrated that BmNPV was not detected in the eggs laid by BmNPV productively infected female moths. The results indicated that BmNPV could not be transovarially transmitted.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.44-52
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• 2002

To understand the relationship among different quantitative traits, correlation studies were performed by utilizing eighty-eight inbred strains of silkworm, Bombyx mori L. on twelve economic characters. Analysis resulted in correlation of 5th instar period with total larval period (r ＝ 0.7882), cocoon weight with shell weight (r ＝ 0.8326), shell weight with shell ratio (r ＝ 0.5067), shell ratio with raw silk ％ (r ＝ 0.7570), raw silk ％ with filament length (r ＝ 0.3490), filament size (denier) with reelability (r ＝ 0.3193) and boil-off loss % (r ＝ 0.2792). Negative correlation was observed among filament length with filament size (r ＝ 0.7582) and reelability with boil-off loss % (r ＝ -0.3236). Correlation of different quantitative characters for quality silk production is discussed.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.53-57
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• 2002

The growth and multiplication of Aspergillus flavus Link and A. tamarii Kita were observed in vitro under variable temperatures of $22-31^{\circ}C$. The matte weight of mycelium and number of conidia/ml were significantly higher (P < 0.01) at the higher temperature than the lower temperature in both the species of Aspergillus. In vivo the mortality in silkworm, Bombyx mori L. with the infection of Aspergillus species was significantly (P < 0.01) different at different temperature and relative humidity conditions.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.2
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• pp.119-122
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• 2006

As the Selenium is known to be growth promoter in sheep and cattle, the efficacy of selenium has been tested in silkworm Bombyx mori L. The V instar larvae were fed with lethal and sub-lethal doses of selenium treated leaves. The larvae fed with lethal dose showed a significant decrease in growth and Cocoon commercial characters. The treatment with sub lethal dose exhibited a significant increase in the growth of the silkworm. Correspondingly, the cocoon commercial characters on exposure to the lethal dose showed significant decrease and sub lethal dose showed a significant increase. In the light of similar findings reported earlier in other cocoon crops and vertebrates, it can be inferred that selenium at lower doses acts as a growth stimulator, resulting in the higher yield of cocoon crop.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.2
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• pp.79-83
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• 2006

We successfully extirpated all four hemopoietic organ-wing disc complexes of the fifth instar larvae of Bombyx mori, and found that most of the treated silkworms could still develop into the moths. We investigated the changes of the circulating hemocytes and evaluated the effects of extirpation on the hemopoiesis. The results showed that proliferation of circulating hemocytes was sufficient to allow development of the silkworms which complexes were totally extirpated. We also found that hemopoietic organ-wing disc complexes extirpation might cause a certain hemopoietic compensation of the remainder complexes during early spinning. Exogenous hormones such as $20-{\beta}-hydroxyecdysone$ and juvenile hormone analog had a positive effect on hemocytes proliferation.