• Journal of Sericultural and Entomological Science
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• v.14 no.2
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• pp.113-123
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• 1972

The authors studied on the effect of silkworm eggs collected from the whole silkworm egg producers in Korea to know the cocoon crops, and the results are as follows. There was no remarkable correlation on the effect of silkworm eggs quality for the cocoon crops but can be concluded as follows. 1) There was a weak correlation between the hatching ratio and economical hatching ratio but no correlation between economical hatching ratio and cocoon crops. In other word, hatching ratio couldn't be influenced for the silkworm health. 5) Non-hybrid ratio (miss-crossing ratio) influenced to the amount of reelable cocoons and pupation ratio but on this experiment, there was a little influence for the cocoon crops. The authors found that there is no difference between origin and its F$_1$crops under the more suitable conditions. Non-hybrid ratio can be determined the silkworm eggs quality, but notice that the ratio decrease only when used pure origin. 3) There is some correlation between harvesting amounts of reelable cocoon and pupation ratio. In general, the eggs which harvest small amounts of reelable cocoon are lower on the pupation ratio. 4) The influence of cocoon layer ratio is based on the variety absolutely but cocoon crops also has a little influence on the cocoon layer ratio.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.41-43
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• 2001

Persimmon fruit moth, Stathmopoda masinissa, collected from roadside persimmon trees planted as shade trees in yeongdong area was used to investigate their developmental ecology under laboratory conditions; $25\pm$ $1^{\circ}C$, 16L : 8D and 85% RH. Developmental periods for eggs, larvae, and pupae were 7.4, 34.8 and 15.5 days, respectively. The duration for each larval instar from the 1st to the 5th was 3.5, 4.2, 5.2, 6.5 and 15.4 days, respectively, and the head capsule width of corresponding stage was 0.20, 0.40, 0.65, 0.87 and 1.07 mm. Rates of pupation and emergence were 68.0 and 59.9%, respectively. Longevity of adult males was 6.2 days while that of females was 10.1 days. Average fecundity was 25.4 eggs.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.171-178
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• 2003

Four thermo-tolerant lines of silkworm, Bombyx mori, (L.) viz., A HT, B HT (Chinese type) and F HT, G HT (Japanese type) were evolved by utilizing the breeding resource material (identified from initial screening at a temperature of 31 ${\pm} 1^{\circ}C$ and relative humidity 85 ${\pm}$ 5%) through conventional breeding. These tolerant lines were crossed with productive breeds and forty four hybrids were evaluated on eight economic traits by the Multiple Trait Evaluation Index Method. Ten hybrids were short-listed based on the average evaluation index value larger than 50 for eight economic traits studied. The identified ten hybrids recorded higher index values (＞ 50) for most of the traits studied. Single hybrid G ${\times}$ CSR12 indicated average index value larger than 50 for six traits viz., pupation number (58), cocoon weight (67), shell weight (65), average filament length (74), raw silk % (69), reelability % (51) except for shell ratio % (41). The standard deviation of the cocoons in the above hybrid was 8.41 in the hybrid cocoon length and width measurement. However, two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 recorded average index value larger than 50 for all the traits viz., pupation number (57, 60), cocoon weight (50, 54), shell weight (56, 57), shell ratio percentage (59, 53), average filament length (55, 60), raw silk percentage (63, 67) and reelability percentage (53, 53). The standard deviation of the cocoons in the two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 was 8.41 and 8.06 respectively in the cocoon length and width measurement.

• Journal of Sericultural and Entomological Science
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• v.48 no.2
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• pp.61-67
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• 2006

We investigated fertilization rate, hatchability rate, pupation rate and cocoon quality etc to selecting good characteristics of the wild silkmoth, Antheraea yamamai using method of indoor-and outdoor-rearing. As results of indoor rearing, the healthiness of A. yamamai was better in light green colour strain than that of dark green colour strain, but cocoon quality was better in dark green colour strain. There was a little effect to selecting major characteristics in grade of A, B and C strain classified with cocoon weight. $F_1$ hybrid was lower in fertilization rate and hatchability rate than parent, but higher in pupation rate and cocoon quality. There was no effect of heterosis in $F_2$ hybrid. In case of outdoor rearing, mortality rate was lower than that of indoor rearing but missing larva was higher. In addition, outdoor rearing is higher that indoor rearing in cocoon weight, cocoon shell weight and cocoon shell rate.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.59-63
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• 2003

In the present study, hybrid vigour in terms of heterosis and over dominance of newly evolved bivoltine hybrids and their reciprocals raised from the promising newly evolved bivoltine breeds were calculated for the important parameters like pupation, cocoon yield, cocoon weight, shell weight, shell ratio, raw silk percentage, filament length and neatness. Through there was no significant difference among the hybrids for the characters pupation, cocoon yield and cocoon weight, the magnitude of heterosis and over dominance were varied significantly for these characters. However, significant differences were observed between new hybrids and control hybrid for the characters like cocoon shell weight, cocoon shell ratio, filament length and raw silk percentage. The results indicate that majority of new hybrids have shown higher heterosis and over dominance than control hybrid. The data also indicate that highest mean heterosis of all new hybrids was recorded for cocoon yield followed by filament length. Whereas highest mean over dominance was recorded for cocoon yield followed by cocoon weight. Negative mean heterosis and over dominance were recorded for the trait cocoon shell ratio. Based on the results, the importance of three hybrids viz., CSR2 ${\times}$ CSR4, CSR2 ${\times}$ CSR5 and CSR3 ${\times}$ CSR6 and their reciprocals (CSR4 ${\times}$ CSR2, CSR5 ${\times}$ CSR2 and CSR6 ${\times}$ CSR3) which exhibited significant heterosis and over dominance, for commercial exploitation was discussed.

• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1046-1052
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• 2007

Transferrin is a molecule carrying iron to store and maintain for iron homeostasis of living organisms. In this study, we have purified transferrin, as an iron-binding protein, from the last larval haemolymph of Papilio xuthus by KBr density gradient ultracentrifugation and gel filtration (superose 6 HR) using fast protein liquid chromatography (FPLC) and transferrin containing iron was identified by Ferene S staining. The purified haemolymph transferrin was shown to have molecular mass of 78 and 80 kDa and amino acid composition of transferrin was rich in aspartic acid, valine, leucine and glutamic acid. With immuno-diffusion assay, we confirmed the existence of the transferrin in the haemo-lymph and fat body by detection of visible and clear positive reaction. From the quantitative comparison by rocket immuno-electrophoresis process, the amount of transferrin were increased in the haemolymph of 3 days after pupation and the whole 5 days after pupation. Here, with biochemical and immunohistochemical analysis, we speculate the relationship of transferrin between the physical characteristics and distribution during metamorphosis of P. xuthus.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.193-197
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• 2000

Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

• Mycobiology
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• v.39 no.3
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• pp.158-163
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• 2011

This study was conducted to confirm the possible use of female Yangwonjam as a host for synnemata production of Isaria tenuipes in eight local areas in Korea. Silkworm pupation rate, infection rate and synnemata characteristics of I. tenuipes were examined. Normal silkworms had a higher pupation rate than silkworms inoculated with I. tenuipes. The pupae survival percentage of normal silkworm in cocoons was 92.5~97.6%, whereas it ranged from 91.1~95.6% in silkworms sprayed with I. tenuipes. Female Yangwonjam showed the highest survival percentage at 97.6% among the silkworm varieties tested. I. tenuipes infection rate of larvae of 5th instar newly-exuviated silkworms was 89.2~90.7% in the spring rearing season and 98.2~99.3% in the autumn rearing season. Synnemata production of I. tenuipes was excellent in female Yangwonjam with an incidence rate of 98.0% followed by male Yangwonjam (94.1%) and Baegokjam (93.3%) in the spring rearing season. Synnemata living weight ranged from 1.44~0.94 g in the spring rearing season. The female Yangwonjam had the heaviest synnemata weight (1.44 g) in the spring rearing season. The synnemata of I. tenuipes produced on pupae were white or milky-white in color, and were similar in shape and color to wild synnemata collected in Korea.

• Korean journal of applied entomology
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• v.32 no.4
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• pp.395-406
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• 1993

This experiment was carried out to develop an artificial diet and a mass rearing system, which is essentIal in the pheromone research for Ostrmia furnacalis. Component deletion and addit.ion methods were applied t.o define the nut.ritional Importance of some components, especially yeast, Wesson's salt mixture and vitamin complex. Secondly we have developed a proper rearmg syst.em for O. furnacalis. and also tried to find out the factors affecting rapid sclerotization (dark-canning) of pupae. AddItion of yeast raIsed the pupal weight. and pupation rate. However Wesson's salt mixture got the female pupae lighter. Vitamin complex as a substitue for yeast showed a good survivahty in an early larval stage buL pupal weight was lower than that of the individuals reared on the yeast dIet. Also corrugated cardboard was found to be very good for pupation. And the rate of dark~tannmg in pupae was higher as the period of larval development was shorter.

• Korean journal of applied entomology
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• v.27 no.4
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• pp.194-199
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• 1988

The seasonal movements of Holotrichia morosa and H. diomphalia in soil were investigated during the period from 1984 to 1986 in Suwon. Most cf the eggs, active larvae and adults of the two species could be found at the soil depth of I-IDem. The larvae began downward movement in late October and early November in order for overwintering when soil tempe¬rature at 5cm below ground reached about $10^{\circ}C$. The overwintering depths of the larvae were 10-40cm for H. morosa and 30-80cm for H. diomPhalia. After the overwintering, pupation and adult emergence of H. morosa occurred at the overwintered sites, \vhereas H. diomPhalia larvae returned to near soil surface next April, and resumed feeding. H.diomphalia larvae began to move downward again in late June for pupation and adult emergence, and overwintered thereafter as adults at the depth of 1O-40cm.