• Current Research on Agriculture and Life Sciences
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• v.18
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• pp.43-51
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• 2000

Eleven inbred lines of silkworm, Bombyx mori L. were exposed to two main different temperature (23C and 25C) during the larval period in order to elucidate the effect of the temperature differences on their main characters under the, prevailing in Egyptial agro-climactic conditions. The results show that the temperature differences did not affect significantly the pupation ratio and cocoon shell ratio. However, they affected their larval duration to become shorter with the high temperature treatment ($27^{\circ}C$) and their cocoon shell weight and cocoon yield per box of silkworm eggs to be higher in the lower temperature($23^{\circ}C$). It was recommended that some inbred lines should be bred at the 23C throughout the whole larval period, particularly in being reared with high nutritional leaves in order to maximize the hybridization of cocoon yields.

• Korean journal of applied entomology
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• v.12 no.1
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• pp.41-46
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• 1973

1) The optimum temperature for mass rearing of stable fly was $26^{\circ}C$ centigrade. Number of days required for stage of development at $26^{\circ}C$ were 6.8 days for larval stage, 5.3 days for pupla stage, 10.4 days for preovipositionla stage, and 30 days for adult stage respectively. 3) The pupation rate, emergence rate and sex ratio were $80.7\%,\;84.3\%$ and 1 : 1, respectively. 3) The average weight of pupae was 14.5mg, and the standard medium showed better result in larvae rearing than wheat bran medium. 4) The optimum number of eggs for inoculation on 125gr medium was approximately 310. 5) Optimum size of resting place was determined as $2inch^2/adult$ when it reared in a rectangular cage.

• Journal of Sericultural and Entomological Science
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• v.9
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• pp.35-38
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• 1969

This study was carried ont to investigate the effect of feeding amount on the metric characters of silkworm at each day of 5 th instar. The results obtained from the study are summarized as follows: 1. The increased amount of feeding did not affect on the metric characters except the character, number of cocoon per litre, by each day of 5 th instar. 2. The decreased amount of feeding did affect the weight of cocoon, weight of cocoon layer and did not affect the pupation, best cocoon rate, cocoon layer rate and number of cocoon per litre by each day of 5 th instar. Namely, the weight of cocoon or weight of cocoon layer was decreased by 12 to 17 per cent in decreasing amount of feeding through 5 th instar. Weight of cocoon or cocoon layer decreased by 5 per cent in the decreasing amount of feeding at just 7 th day of 5 th instar.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.97-101
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• 1965

This work was carried out to investigate the relation between the fat content and the metamorphosis as the silkworms grew. The results obtained are as follows: 1. The content, of which the dry matter had been 24% at the stage of newly hatched silkworms, were gradually decreased by feeding on, but suddenly increased to the 28.5% at the mature stage. Those decreased slightly from pupation to just before the moths, and again increased to the 32% of the dry matter when became the moths. 2. The content, of which the fat had been 16.2%, however, decreased as the silkworms grew. The fat content increased little by little from the first feeding to the vigorous eating, but the matured worm contained only 15.7% of the fat. 3. The fat content of both male and female showed an increase to 23.5% and 35.7%, respectively. After that, the contents of it decreased to 12% and suddenly increased to 26% just before the moth in female. In male the content of fat showed a slight increase till before the moth, and after moth became, it were 42.5%.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.1
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• pp.7-14
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• 2006

A breeding programme was initiated during 2001 to introduce sex-limited larval markings to a productive multivoltine breed - BL67 from an inbred sex-limited line, MY1 (SL) maintained at Central Sericultural Research and Training Institute, Mysore. Introgressive hybridization, recurrent backcrossing for six generations followed by sib-mating resulted in synthesis of a new multivoltine silkworm breed BL67 (SL) with sex-limited larval markings. The new breed was studied for combining ability by crossing with eight bivoltine breeds viz., $NB_4D_2,\;CSR_2,\;CSR_2 (SL),\;CSR_2,\;CSR_4,\;CSR_8,\;CSR_{18}\;and\;CSR_{19}$. General combining ability effects of the new breed showed its superiority over the popular Pure Mysore by expressing significant GCA effects for six out of twelve characters whereas the results are on par with the original multivoltine breed. The hybrid $BL67(SL){\times}CSR2(SL)$ excelled in several quantitative characters such as pupation rate (90.2%), cocoon weight (1.97 g), cocoon shell weight (40 cg), cocoon shell ratio (20.3%), filament length (918 m), denier (2.96), raw silk percentage (14.96%) and neatness (90 p). Studies on cocoon size variability revealed that the cocoons of $BL67(SL){\times}CSR2(SL)$ were found comparatively uniform showing less standard deviation of 6.55 and co-efficient of variation of 3.91 %. The suitability of newly developed breed for easy grain age operation and commercial exploitation with promising hybrid have been discussed.

• International Journal of Industrial Entomology and Biomaterials
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• v.18 no.2
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• pp.63-67
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• 2009

To increase utilities as functional materials, 173 strains of silkworm genetic resources in the form of silkworm powder were evaluated for antioxidative capacity, with minilum L-100 device and ARAW-KIT (anti-radical ability of water soluble substance). Silkworm powder was prepared with freezing method from silkworms at 5th instar 3rd day larvae. All strains of silkworm powder were prepared with 80% methanol extraction. The data of pupation rate, longevity of silkmoth with origin and voltinism were used for data base of silkworm genetic resources. The weight of a silkworm larva with freezing method at 5th instar 3rd day was measured. The average of antioxidative capacity of 173 silkworm strains was 429.68 nmol. The analysis of correlation among variables was significant, showing negative correlation of the antioxidative capacity with longevity of silk moth and weight of 5th instar silkworm larva. The strains from the tropic, Europe and some other origins were comparatively high. In conclusion, short longevity and low weight of 5th instar silkworm larvae showed comparatively effective antioxidative capacity.

• The Korean Journal of Zoology
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• v.29 no.1
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• pp.1-12
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• 1986

Electrophoretic, immunological, and column chromatography methods were used to determine the appearance and distribution of storage proteins in various organs during the metamorphosis of Bombyx mori L. Two storage proteins start to appear in haemolymph in early 5th instar stage and show the identical mobility with fat body proteins. These proteins show the high concentration in haemolymph in last instar stage but accumulate in fat body after pupation. Storage protein-2 shows the distinct pattern for general storage proteins in both male and females. This protein is involved with the formation of cuticle protein in late last instar stage and appears to be temperally deposited in midgut during the pupal stage. Also SP-2 shows the identity with vitellogenin electrophoretically and immunologically and especially the positive reaction with antibody against yolk protein during the pupal stage, demonstrating that the storage protein is closely related to the formation of yolk protein.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.180-185
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• 1996

Biosynthesis tracing of the silk fibroin in Bombyx mori silkworm was examined in vivo with isotopic [1-13C] Gly. labeling by nuclear magnetic resonance method. The [1-13C] Gly. labeled silk fibroin yielded very sharp 13C NMR signal in the posterior silk gland as well as in aqueous solution and the amound of [1-13C] Gly. labeled signal in the silkworm increased gradually and rapidly to 5-th day of fifth instar. However, the decomposition or decrease of the [1-13C] Gly. labeled signal occured from 5-th to 9-th day of fifth instar unexpectedly. These findings suggest that a relative amount of ${\alpha}$-helical portion or amorphous silk II portion was formed without any further signal from 6-th day of fifth instar to pupation. Through peak separation of orientation spectrum, between the fiber axis and the molecular bond direction, N-H bond in Bombyx mori silk fiber as well as the orientation distribution around the silk fibroin axis were determined and two kinds of peaks were also obtained from this orientation spectrum.

• Korean journal of applied entomology
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• v.45 no.1 s.142
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• pp.91-95
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• 2006

This paper reports a simple rearing system for Cnaphalocrocis medinalis based on corn seedlings diet. C. medinalis population under this system has been maintained by four stages (egg, young larva-1st to 3rd instar, old larva-4th to prepupa, 3nd adult) at $25{\pm}2^{\circ}C,\;40{\pm}10%$ RH, 3nd 16L:8D photoperiod in a laboratory. We have elaborated a new egg collection method using a polystyrene container $(top\;{\phi}11.3\;{\times}\;bottom\;{\phi}\;{\times}\;H8cm)$ which has made a great contribution in easy collection of eggs and storage of them for long period. Under this system, pupation and adult emergence rate, and pupal weight of C. medinalis population were close to the other reports by com seedling diet, and superior to those by artificial diets. Therefore, this rearing system would be useful in obtaining C. medinalsis population suitable to each specific needs.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.286-293
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• 1990

Studies were carried out to investigate the change in protiens and carbohydrates from diapausing pupae of the Oriental tobacco budworm, Heliothis assulta Guenee. The oxygen consumption rate of non-diapausing pupae through the whole pupal period showed an U-shaped curve, while that of diapausing pupae decreased to a mean level of 20$\mu$1/g/hr. But the rate of oxygen consumption increased in diapausing pupae before their emergence. The body weight of diapausing pupae showed almost no change during 12 days after pupation. The total contents of major carbohydrates and soluble proteins were higher in diapausing pupae than those in non-diapausing pupae and the change in carbohydrate and protein contents was more dynamic in non-diapausing pupae than that of diapausing pupae. the electrophoretic band patterns of proteins were similar in both of diapausing and non-diapausing pupae. Diapausing pupae increased their haemolmph osmolarity further when they were exposed to low temperatures.