• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.125-132
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• 2003

Uzi fly (Exorista bombycis Louis) is one of the major larval endo-parasitoid of silkworm (Bombyx mori). It causes extensive damage to sericulture industry. The application of synthetic organic pesticides has tremendous impact on minimizing pest population but their overuse and frequent misuse and high sensitivity towards the silkworms, has forced the entomologists to search for alternatives to chemical control, which is safe to silkworm, environment and farm workers. Biological control continues to offer exciting possibilities for the control of fly pest population. It is environmentally safe alternative to chemical control and offering a long-term protection. Several potential hymenopteran parasitoids have been screened. Among successful natural enemies, Nesolynx thymus, Trichomalopsis apanteloctena, Trichopria sp., Brachymeria lasus, Pediobius sp., Spalangia sp., Spilomicrus karnatakensis and Dhirhinus sp. are important. It is essential to predict accurately the efficacy of these natural enemies in a new habitat prior to its introduction. The important desirable attributes of these potential parasitoids viz., host searching capacity, specificity, power of increase and fitness and adaptability of the parasitoid in new environment has been recorded. Results of the host parasitoid interaction indicate that the aging of the host function as a factor that influence the host finding efficiency of the parasitoid. It is highly scored with 15-20 hrs old pupa of the host. However, aging of the parasitoid does not significantly affect it. The sex ratio is female biased which is advantageous from biological control point of view, Biological suppression methods involving conservation and utilization of natural enemies have been discussed in detail.

• Journal of Sericultural and Entomological Science
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• v.35 no.2
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• pp.105-113
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• 1993

To produce F1 hybrid of silkworm sex discrimination has to be followed at the pupal stage by sexual organ. However it requires a lot of labour and may bring about a wrong classification. In these regards, this study has been implemented to find out an effective measure for the pupal sex discrimination by use of variation of cocoon weight and image analysis of cocoon. As a result, it was found that in case of the pupal weight the percentage of a wrong classification fell on 0.3% and in case of single cocoon weight 0.4%. The discrimination rate was 99% in the weight variables of cocoon but analysis by single cocoon weight and cocoon shape variables, it was 98.7%. Efficiency of discrimination was increased by 2.7% as compared to variable of single cocoon weight. The minimum cocoon sampling size may be 15 cocoons sexual-wise.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.51-62
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• 1968

This study was carried out to investigate the life cycle and the damage of Tricholyga sorbillans Wiedmann to silkworms(Bombyx mori L.). The results are summarized as follows. 1. This insect has 5 or 6 generations per year in Suwon area. 2. The egg, larval, and pupal stage are about 2, 8 and 18 days respectively. 3. The weather conditions considerably affect the life cycle, that is, the 3 rd generation is the shortest of all, lasting for 21 days and l4 hours, and the 5th generation is the longest for about 40 days. 4. The larvae come out of silkworm bodies, burrowing into the ground 3.5cm to 10.5cm in depth before changing into the pupae. 5. This insect does not overwinter as pupa, but seems to do as larva, parasiting on the field insects. 6. The damage of Tricholyga sorbillans Wiedmann to silkworm was 27.9％, it is so high that the silk worms could not be reared outside without a reasonable control method. 7. When the full-grown silkworm is parasited by one egg of these insects, there is not only enough possibility of spinning. but also without any effects of their larvae on the cocoon quality. 8. The damage of Tricholyga sorbillans Wiedmann throughout the country covers 6.36％ in spring, 4.09％ in fall, and 5.25％ yearly mean.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.54-64
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• 2010

Effects of thirteen essential oils (anise oil, clove oil, marigold, mustard oil, neem oil, quassia, quilaja, rosemary oil, rotenone, tea tree extract, thyme oil, wintergreen oil, and yucca) and caffeine on typical industrial insect, silkworm (Bombyx mori) and two entomopathogenic nematodes, Steinernema carpocapsae GSN-1 strain (Sc) and Heterorhabditis sp. Gyeongsan strain (Hg) were investigated in the laboratory. When 1,000 ppm of each essential oils was treated, neem oil showed the highest insecticidal activity against silkworm. Mortality of silkworm fed on neem oil treated mulberry leaf was 55.3 and 100% 5 and 10 days after treatment, respectively. The silkworm fed on neem oil treated mulberry leaf did not make cocoon and pupa. Weight of cocoon and pupa was low in rotenone treatment showing 0.27 g and 1.01 g, respectively. Mustard oil had the highest nematicidal activity against entomopathogenic nematodes. 20 ppm of mustard oil resulted in 69.0% and 100% mortality of Sc and Hg 3 days after treatment, but 4% and 36% at 5 ppm in X-plate, respectively. Mortality of baited Galleria mellonella larva by Sc was not different from control at the concentration of 100 ppm of mustard oil while 30% lower in Hg in sand barrier. Mean numbers of established infective juveniles of Hg in Galleria larva were lower than Sc in sand barrier. Survival rate of Sc was similar to control at the concentration of <200 ppm of mustard oil in sand barrier.

• Journal of Sericultural and Entomological Science
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• v.6
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• pp.42-48
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• 1966

Throughout the studies the following experimental results were obtained and so are summarized here. 1) What caused tussah silkworms terrible disease broken ous all over the Korea in 1965, was examined to be “Inclusion body of virus” through microscope. 2) The examined inclusion bodies are easily stained as purple by seller's staining. 3) The proper speed of centrifugation for the purification of inclusion bodies is 1,000 r. p. m for 10 minutes. 4) It is possible, cleanly resulted, to attempt the “Rapid Agglatination Test ＆ Complement Fixation test” with autigen of inclusion bodies. 5) The Anti-polyhedra rabbit serum from antigen of the dilution of 2${\times}$10$\^$6//l$m\ell$ polyhedra made the Ropid Agglutination test possible even with dilution of 1/8 infected pupa blood(antigen).

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.380-386
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• 1998

To obtain basic data for mass production of Isaria japonica, cultural characteristics of japonica were investigated by using liquid, solid media and silkworms pupa. Mycelia grew favorably at the temperature of $23{\sim}28^{\circ}C$ on MYG medium with pH 7.0. The fruiting-body of I. japonica was induced below $20^{\circ}C$ in MYG liquid medium (Malt yeast glucose) under fluorescent light. In MYG basal medium mixed with pupal powder of silkworms, the fresh weight of fruiting-bodies was increased with increasing concentration of pupal powder. The highest yield of fruiting bodies was obtained in carbon-rich medium supplemented with pupal powder of silkworm. Also, fruiting-bodies of I. japonica were produced massively on the silkworm pupa placed on the stainless tray in the shortest time. The structure and shape of fruiting-bodies were coral-like, many-branched types with numerous conidiospores.

• Journal of Sericultural and Entomological Science
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• v.13 no.1
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• pp.31-34
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• 1971

The pupa (7th. day after mounting) were irradiated for foully minutes with 1,000${\gamma}$-ray and the copulation was done under the various conditions when the pupa grew to be imagos. The silkworm eggs that the imagos laid were divided into many groups by five, fifteen, foully-five, ninety, seven-hundred, twenty and twenty-four hundred minutes eggs respectively and the lipid phosphorus in the each group of eggs was analyzed as follows. 1. The quantity of 928${\gamma}$/100mg dry powder (D. P.) was shown in the group of the fourt-five minutes eggs whose ovum nucleus and sperm nucleus were not conjugate in the control C (male and female). The number of the greatest quantity of 944${\gamma}$/100mg D.P. after the syngamy of ovum nucleus and sperm nucleus while the smallest quantity was 768${\gamma}$/100mg D.P. in the group of ninety minutes eggs. 2. Not much difference could be seen the copulation group of female irradiation and male control and the copulation group of male irradiation and female control compared to the both male and female control group, but the influence could be seen in the group of irradiated female pupas. 3. The great difference could be seen in the group of irradiated male and female pupa compared to the control group. The five minutes eggs showed the smallest quantity of 536${\gamma}$/100mg D.P. and the quantity of lipid phosphorus rapidly began to increase from the fifteen minutes eggs. The quantity amounted to 1,082${\gamma}$/100 mg D.P. in the case of seven hundred and twenty minutes eggs while the quantity decreased in the twenty-four hundred minutes eggs which showed 912${\gamma}$/100 mg D.P. The general result obtained in the present study was that the irradiated male and female pupa were greatly influenced before and after the syngamy of gamete.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.169-174
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• 2008

The growth characteristics of Paecilomyces tenuipes according to the passage in the two kind of liquid media were investigated by comparing the mycelium and conidium formation degrees. The potato dextrose broth medium and the silkworm larvae medium containing the silkworm powder were used as the liquid media, and the potato dextrose agar medium and the brown rice medium containing the powder of silkworm pupa were used as the solid media. The conidium formation degree in liquid media differed by the passages but that in solid media was not. This suggested that the passage in liquid media did not affect significantly the conidium formation in solid media. When the brown rice media were inoculated with the concentration of $1{\times}10^{10}$ conidia/ml, $1{\times}10^8$ conidia/ml and $1{\times}10^6$ conidia/ml, respectively, the conidium formation degrees were similar. This indicated that the optimal inoculation concentration of conidium to the brown rice media is $1{\times}10^6$ conidia/ml.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.1
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• pp.107-113
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• 2011

Infection effect of $Nosema$ $bombyics$ on the midgut of silkworm $Bombyx$ $mori$ and subsequent appearance of spores and the performance of larvae was studied. Autopsy of larvae showed white pustules on the surface of midgut at 5 days of post infection (pi). At later stage, important organs like midgut, silk gland and gonads reduced in size and all these organs showed white pustules. Light microscope observation of pustules revealed enormous spores. Spore multiplication was at a faster rate in young larvae. Infection of the adult larvae resulted in pebrinized pupa and moths. Larval weight, cocoon weight and cocoon shell ratio reduced as the post infection period increased. Transverse sections of midgut showed $N.$ $bombycis$ infection limited to a few columnar cells at 3-5 days of pi. At 7 days pi, cell volume increased, cells were swollen and elongated. Heavily infected cells looked like sacks filled with parasite and the apical region of certain cells were bulging into the gut lumen. Later at 8-9 days of pi, spores or its developing stages leaked into the lumen either freely or enclosed within the globules of host cytoplasm. Besides columnar cells, development of $N.$ $bombycis$ was observed in the regenerative cells and rarely in goblet cells. Development of $N.$ $bombycis$ was also observed in both longitudinal and circular muscles at the late pi period. The histopathological changes, deformities and spore production time in the host were all influenced by the spore dosage and age of the host.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.59-65
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• 2004

Hot water-extracts prepared from Cordyceps militaris of silkworm pupa (CMP) or Cordyceps militaris of silkworm larva (CML) were tested for tumor growth inhibitory and immunomodulatory activities in ICR mice bearing sarcoma-180 cells solid tumor, and compared with those of the known compound, cordycepin, found in Cordyceps militaris. Mice were subcutaneously injected with sarcoma-180 cells, and i.p. injected with either saline (Control), 50 mg/kg or 100 mg/kg of CMP (CMP50 or CMP100, respectively), or CML (CML50 or CML100, respectively), or 1 or 2 mg/kg of cordycepin (C1 or C2, respectively) for 10 days. Mice injected with CMP50 or CMP100 showed a 47.3% or 57.6% inhibition in the solid tumor growth (P<0.05), while those injected with CML50 or CML100 exhibited a 35.5% or 37.1% reduction (p<0.05) in solid tumor size compared to the value for control mice treated with saline. Animals injected with corcycepin showed a 26∼30% inhibition in the solid tumor growth (P<0.05). Mice bearing solid tumor and injected with CMP or CML showed a significantly increased thymus weight (38∼44% increase), lymphocyte percentages of CD4+ T-cell, CD8+ T-cell, and NK-cell (63∼110% increase) in the spleen, and interleukin-2 excretion (33∼51% increase) by the isolated splenocytes compared to those in control mice (p<0.05). These results indicate that the anti-tumor activity of hot water extracts of Cordyceps militaris, raised on both silkworm pupa and silkworm larva, appears to be associated with their immunomodulatory activity, and these activities found in Cordyceps militaris are superior to those for the single compound, cordycepin.