• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.115-118
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• 1994

Differences of feeding response of 280 silkworm genetic stocks and 71 breeding lines to MP-O artificial diet and the mode of the inheritance were investigated. Feeding response to MP-O diet varied markedly between the silkworm varieties, and the non-normally distributed curve for the response was observed. From the genetic analysis, the high feeding response to MP-O diet was recessive to the low feeding response. Therefore it is considered that the high feeding response of the newly hatched silkwrom larvae to MP-O diet is controlled by a recessive gene.

• Journal of Sericultural and Entomological Science
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• v.19 no.1
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• pp.5-7
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• 1977

On the purpose of exploiting cellulose resourse which is needed for artificial diet of silkworms, mulberry branch, eastern cotton wood branch, pitch pine pulp, poplar pulp, chaff, sawdust and rice straw were examined. Among the matters above mentioned. mulberry branch and pitch pine pulp were found to be replaceable as cellulose component in the artificial diet. By means of some chemical treatments, it is found that one of the extracted cellulose powder from mulberry branches is more useful in the larval growth.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.28-35
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• 1993

Treatment of juvenile hormone analogue(JHA) at the 5th instar larvae prolonged the duration of adult development one to one and half days as well as the elongation of feeding time with the increasing of larval body weight. Morphological observation and protein analysis in hemolymphs, integuements, alimentary canals, fat bodies and ovaries also revealed that the development of these tissues and organs for adultation are affected by the JHA treatment.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.82-86
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• 2015

This study was carried out to develop the silkworm rearing technique in unused mulberry leaves after harvesting mulberry fruit. The growth of Gwasang No. 2 and Suhyang was very good compared to control cultivar Chungil in leaves size and new branch growth, but new branch and leaves of Daeshim was similar or small to control cultivar Chungil. The number of leaves of Gwasang No. 2 and Suhyang was lower than Chungil, but weight of leaves per tree was heavyer than Chungil. Mulberry leaf yield was Gwasang No. 2 521 kg/10a, Suhyang 189 kg/10a, Daeshim 73 kg/10a, Chungil 1,095 kg/10a. Content of mineral element of all three mulberry cultivars leaf for mulberry fruit production was higher than Chungil in N, P, K, Ca etc. Feeding quantity of silkworm of Gwasang No. 2 and Suhyang was much more than Chungil. Feeding quantity was highest at Suhyang in 96 kg/box. Growth duration of silkworm larvae was not different in all four mulberry culivars but weight of silkworms (5th instar 3rd day) was heavy at Gwasang No. 2 (2.07 g/head) and Suhyang (2.11 g/head) compared to control cultivar Chungil (1.92 g/head). Mortality of silkworms was 14.6% (Gwasang No. 2), 13.3% (Suhyang), 13.9% (Daesim), 12.6% (Chungil) and than higher at elder instar stage. The production amount of silkworm (5th instar 3rd day) was 35.4 kg/box (Gwasang No. 2), 36.6 kg/box (Suhyang), 35.0 kg/box (Daeshim), 33.6 kg/ box (Chungil). Amount of possible rearing silkworms was estimated 3.4box/10 a (Gwasang No. 2), 1.3box/10a (Suhyang), 0.5box/10a (Daeshim), 8.7box/10a (Chungil).

• Journal of Sericultural and Entomological Science
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• v.34 no.1
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• pp.1-7
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• 1992

For a long-term preservation of silkworm stocks by frozen gonad storage, fundamental topics such as freezing rate and transplanting stage of the gonad, proper cryoprotectant, and super-cooling temperature and freezing point of the freezing medium were examined and following results were obtained. Proper method to anesthetize the ovary-recipient silkworm was to dip the animal to cold water for 10 minutes, and the ovary taken from the 4th instar larvae was more suitable for freezing-preservation than that from the 5th. Concerning the cryoprotectant, glycerol and DMSO were effective to prevent cryoinjury of the ovary, but sorbitol was not. The supercooling temperature and freezing point of the medium to freeze the ovary and testes were checked, and consulting with the results desirable cooling rate was confirmed. On the desirable conditions of transplanting methods, freezing rate and cryoprotectant concentration ect., the next generation was obtained when the females implanted frozen-thawed ovaries mated with normal males, but none of the normal females mated with the males implanted frozen-thawed testes laid fertilized eggs. Now it is needed to improve the connecting ration of the ducts associated with the transplanted testis to those of the hosts.

• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.73-77
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• 2013

Silkworm transgenesis scientists have done some genetic modification work on multivoltine silkworms, but that type of silkworms is less commercial feasible. They are easy to manipulate, because they breed all year round. But the commercial silkworm variety must undergo hydrochloric acid treatment at a high temperature to be artificially hatched. Hydrochloric acid penetrates through the holes in the silkworm eggs, fatally damaging their reproduction. So it had been thought that altering the properties of the commercial silkworm variety would be very difficult. So we have tried to make from diapause to non-diapause eggs using diapauses varieties, 'Backokjam' and 'Jam 124'. At present, our group has establishing the conditions for non-diapause eggs. Oviposited eggs after 40 ~ 60 hours were incubated for 24 hours at $15{\sim}20^{\circ}C$ with dark condition. Non-diapause eggs were completely induced. The hatching rate, molting rate and pupation rate of non-diapause 'Jam 124' and 'Backokjam' eggs showed no differences compared to diapause eggs. When transgenic silkworm using the non-diapause eggs, the hatching rate showed that non-diapause eggs induced from diapause were 40 ~ 70%, diapause eggs treated with artificial incubation were 10 ~ 30%, and polyvoltine strains, HM eggs were 30 ~ 50%. Therefore, we suggest that modification techniques of the commercial silkworm eggs adequate for silkworm transgenesis can be used to develop transgenic silkworms more easily.

• Korean Journal of Organic Agriculture
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• v.11 no.1
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• pp.67-77
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• 2003

This study was conducted to established method of culture for Paecilomyces japonica using an egg. Mycelia grew favorably at the temperature of 22～26$^{\circ}C$ on eggs. 5.1g of dry matter basis(average 7.2cm of longer and 199.6 of numbers) of artificial fruiting bodies were harvested at 60 days after inoculation from one of egg. Commercial fruiting bodies of Paecilomyces japonica from silkworms was used for comparative nutriental contents. Cordycepin contents of fruit bodies of Paecilomyces japonica cultivated on eggs and silkworms were not significantly different. Crude fat contents of fruiting bodies of Paeilomyces japonica cultivated from eggs was significantly higher than from silkworms(P<0.05). Mn and Cu contents of fruiting bodies of Paecilomyces japonica cultivated from silkworms were significantly higher than from eggs(P<0.05), but Na, Mg, Fe and Zn contents were significantly higher from eggs(P<0.05). Glycine, Arginine and Proline contents in the fruiting bodies of Paecilomyces japonica cultivated from silkworms were tend to higher than from eggs, but Serine, cystein. methionine, isoleucine and phenylalanin were tend to higher from eggs. These results were made possible that possible mass production of artificial fruiting bodies of Paecilomyces Japonica cultivated on eggs.