• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.6-9
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• 2003

This experiment was done to know developmental characteristics of Sericin jam. Incubation periods were 10 day 2 hr, and 10 day 1 hr. 11 day 1 hr for Nd-s jam, N $d^{H}$ jam, and Baegok jam, respectively. Hatching rates were 83.9, 83.3 and 96.0% for Nd-s jam, N $d^{H}$ jam, and Baegok jam. Larval periods were, 20 days 1 hr for Nd-s jam, 20 days 5 hrs for N $d^{H}$ jam, and 22 days 12 hrs for Baegok jam. Death rate of larvae was highest in N $d^{H}$ iam, followed by Nd-s jam and Baegok jam. Pupation rate was highest in Baegok Jam followed by Nd-s jam and that of N $d^{H}$ jam was the lowest among the three. Cocoon weight was 1.39, 1.08, and 2.01 g for Nd-s jam, N $d^{H}$ jam, and Baegok jam, respectively. Shell weight were 13, 3, and 48 cg for Nd-s jam, N $d^{H}$ jam, and Baegok jam. Cocoon shell ratios were 9.0% for Nd-s jam, 2.8% for N $d^{H}$ jam and 23.9% for Baegok jam. Cocoon sizes were 30.6${\times}$15.8 mm for Nd-s jam, 24.7${\times}$14.9 mm for N $d^{H}$ jam and 35.8 ${\times}$ 20.5 mm(1${\times}$w) for Baegok jam.w) for Baegok jam.

• Journal of Sericultural and Entomological Science
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• v.49 no.1
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• pp.24-27
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• 2007

Silkworm fed on the mulberry leaf mixed with silver nanoparticle to produce silver-nanoparticle embedded cocoon. Comparative analysis of silver content of cocoon shell, percentage of pupation and percentage of cocoon-shell weight showed that the optimum concentration and the feeding period of mulberry leaf mixed with silver nanoparticle were 500 ppm and the period from 3 day 5 instar to mounting of silkworm. The silver content of cocoon was observed variously by silkworm breedings. C212 variety makes pale yellow cocoon with the highest silver content(69%). Using the scanning electron microscope, we showed that the size of silver nanoparticles in silk was observed from 26.98 to 99.81nm. Silver-nanoparticle embedded silk is expected to use as high valuable application owing to the different functional properties including antibiotic characteristics and mechanical and electronic properties. The applicable fields expected is antistatic and/or electronic products with biological degradable natural materials.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.126-132
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• 2012

Two different feed(bran and swine feed) effect was tested on development of Tenebrio molitor at $25{\pm}5^{\circ}C$, $65{\pm}10%RH$. There was no significant feed effect on larval developmental periods(80.0 ~ 83.7 days), pupal length (18.1 ~ 18.7 mm) and fecundity(44.3 ~ 55.3 eggs) during first two days. However, fecundity was significantly affected by the pupal weight(P < 0.05), such that the number of eggs 172.3, 191.2, 215.0 gradually increased as pupal weight rose from 0.12 g, 0.15 g to 0.18 g, respectively. During the first two weeks of oviposition was 51.8%, which gradually decreased for further days. Longevity was $27.1{\pm}6.9$, $30.1{\pm}7.8$, $27.4{\pm}8.5$ days with increasing pupal weight of 0.12, 0.15, 0.18 g, respectively. Larval densities of 100, 300, 500 and 700 individuals reared in the container ($16{\times}21.5{\times}7cm$) resulted 67.9% of the T. molitor pupation during first three weeks. Pupal weight was decreased $146.9{\pm}6.5$, $142.1{\pm}8.3$, $122.0{\pm}9.6$, $118.5{\pm}5.2mg$ when it was reared at different larval densities of 100, 300, 500 and 700 individuals, respectively in size of($16{\times}21.5{\times}7cm$) rearing container.

• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.172-177
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• 2024

Many studies have reported that mealworms can ingest plastic during their larval stage. The purpose of this study was to investigate the effects of expanded polystyrene consumption on the growth and development of mealworms during their larval stage. We found that the growth rate is significantly different between mealworms consumed wheat bran and mealworms consumed expanded polystyrene (p < 0.001). The transformation into pupa occurred faster among the mealworms consumed expanded polystyrene than those consumed wheat bran (p < 0.001). However, the survival rate was not significantly different between the two groups of mealworms (p = 0.786). Based on the data, we conclude that mealworms consuming expanded polystyrene have a slower weight gain and a shorter development period than mealworms consuming wheat bran, but the expanded polystyrene does not affect the survival rate before the transformation into pupa. Practically, we anticipate that mealworms can be a resource for the sustainable and eco-friendly removal of expanded polystyrene waste.

• Journal of Sericultural and Entomological Science
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• v.53 no.1
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• pp.12-18
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• 2015

This study was conducted to consider practical use of F2 hybrid and intervariety crossing for the improvement of silkworm eggs export and silkworm eggs manufacture. Now Kumokjam and Baegokjam come into wide use to sericulture farmers but comparison test of F1, F2 hybrid and intervariety have not been done. We weighed against the productivity among economical character. While larval period of F2 among them is most long time, pupation percentage and cocoon yield per 10,000 3rd molted larvae are lower than intervariety. With comparing F2 and intervariety, single cocoon weight of F2 is lower 9 ~ 21% than intervariety, and cocoon shell weight of F2 was lower 10 ~ 18% than intervariety. By number of cocoons per liter, F2 hybrid was lower and more irregular size than intervariety. In coparison with number of egg laid, F2 hybrid Baegokjam was 655 ea (14%) and Kumokjam 625 ea (40%) more than F1 hybrid. Also, F2 hybrid for filament grade went down than F1 hybrid. The advantage of egg production in F2 hybrid can reduce costs because there is no necessity for sex discrimination and germination control. But besides increase of number of egg laid, the productivity including economical characters was greatly lowered. Except for being a lot of laying eggs, cocoon productivity of the F2 was greatly reduced by degeneration of practical traits. Therefore the further studies are needed in order to increase utilization value of the F2 hybrid silkworm.

• Journal of Sericultural and Entomological Science
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• v.17 no.2
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• pp.141-149
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• 1975

Silkworm is known to be damaged under the unfavorable environmental conditions. Recently, it has been often argued that nicotine is a main factor to affect the silkworm nutritional balance and to result in decrease of quantitative characters, and unbalance of larval nutrition. Especially in spring season, there is tendency to produce nicotine damage to silkworm fed with the mulberry leaf near to tobacco field early cultivated in mulching system. In these connections, the trial was made in the different pots placing by the different distance 10rn, 20m, 40m, and 60m in the direction of east-north from the tobacco field. Location of pot near to the tobacco fold is 40m below the tobacco Held and gradually higher than the tobacco field by 10 degree of slope. In addition, when the mulberry field is divided into two areas from the east-south to west-north, southern east zone is lowering down below 10 degree of slope and has 36％ of east-south wind, 21％ of south-east wind and 16％ of south wind, etc. Pots are left on the mulberry field from the completion of lower part leaf harvest to just before upper part leaf harvest is completed for 32 days. Then silkworm at 4th-5th stage was fed with the leaf grown during the period and larval characters are statistically analyzed. The results are summarized as follows： 1. 10-40m distant pot statistically at the same level has the longest larval duration and 60m distant pot is. not significant at 5％ level. Whole larval duration has same tendency as in the 5th larval duration. 2. Percentage of delayed molting larvae at the 5th stage is increased in 10m distant pot and there is no significance statistically in other pots, as compared with that of control. 3. It is not showed that there is no damage to mortality of the old larvae in 60m distant pot. 4. 10-20m distant pot produces a low pupation and others are at the same level statistically at 5％ significance, 5. It is showed that nicotine damage is occurred in single cocoon freight and cocoon shell weight up to 60m distant pot, rather higher damage in cocoon shell weight than in single cocoon weight. 6. It is showed that cocoon yield from 10, 000 molted larvae including double cocoon is decreased up to 40m distant pot far from the tobacco field in which 40％ of cocoon yield in 10m distant pot by 7kg, 26％ of cocoon yield in 20m distant pot by 3.9kg, 24％ of cocoon yield in 40m distant pot by 3.6kg, and 12％ of cocoon yield in 60m distant pot by 1.8kg, as compared with control. However, there is no significance statistically at 5％ level in 60m distant pot. With these above results, it is concluded that nicotine da mage could be occurred in cocoon yield and cocoon quality up to 60m distant far from the tobacco field.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.97-104
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• 2018

The larva of the white-spotted flower chafer, Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae), is known to have important medicinal properties, such as anti-cancer activity. However, the consumer market for the larvae is depressed because of its high production cost which needs to be reduced. This study was carried out to evaluate two spent mushroom substrates as food source for chafer larvae to improve the productivity and reduce production cost. The larvae were fed with spent substrates of king oyster mushroom (Pleurotus eryngii) (P-SMS) and shiitake mushroom (Lentinula edodes) (L-SMS), with a control of fermented oak sawdust. Effects of the diets on the development of P. brevitarsis seulensis and contents of minor nutrient components in the larvae produced were examined. In the P-SMS diet, the larval rearing period was shorter at 16.2 days, while the rate of larval weight gain and the cocoon weight were higher at 156.3% and 4.1 g, respectively, than that in the L-SMS diet. The pupation rate was 100% and the adult emergence was higher at 93.3% in the P-SMS diet than in the L-SMS diet with no difference to the control diet. In the P-SMS diet, the total nitrogen content during rearing was higher at 10.28% and the minor nutrient component, particularly Fe (145.8 mg/kg), was higher than that in other diets. The oviposition preference of adults showed no significant difference among the diets. Economic analysis showed that P-SMS costs approximately 667,960 Won less per 100 kg of larvae produced, compared to that of the control diet.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.77-82
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• 1997

This study was carried out to investigate the developmental characteristics and life cycle of sciarid fly (Lycoriella sp.), an important mushroom pest. The sciarid fly was reared ina growth chamber at 21$\pm$$1^{\circ}C$ and 55$\pm$5% of relative humidity with a 16h high, 8h dark cycle and Flammulina velutipes was used at diet. The egg was oval with 0.17 mm in diameter and 0.27 mm in length. Average egg period was 4 days. Body length of each instar from the 1st to 3rd was 0.7, 1.5, and 4.5, mm. respectively. Average weight of each instar was 1.9, 15.4 and 93.6 $\mu\textrm{g}$, respectively. In the 4th instar larvae, however, developmental characteristics of female and male became different by body length, weight and segment size. Body length and weight of the 4th instar female larvae were 5 mm and 162$\mu\textrm{g}$, and those of the male larvae were 3.5 mm and 90 $\mu\textrm{g}$, respectively. The larval periods of female and male were respectively 13.5 and13 days. Pupal length of female and male was 3.5 and 2.7 mm, and average weight was 136 $\mu\textrm{g}$ and 6.5$\mu\textrm{g}$, respectively. Adults were emerged from female and male pupae on 5.5 and on 5 days after pupation, respectively. Average longevity of male and female were 7 and 5 days, respectively. The weight of female was two-fold heavier than the male. After copulation, female laid approximately 130 to 150 eggs on/in the sporophore of mushroom. In conclusion, total lifespan of male and female were 29 and 28 days, respectively.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.135-140
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• 2000

Development and reproduction of the cotton caterpillar, Palpita indica, were investigatedunder different temperatures (15 .O, 17.5, 20.0, 22.5, 25 .O, 27.5, 30.0, 32.5, and 35 .O$^{\circ}$C). Duration fromegg to pre-adult of the cotton caterpillar were ranged from 68.6 days at 175$^{\circ}$C to 19.7 days at 35.0% (3.5times shorter growth period compared with that at 17S$^{\circ}$C). At 15.0$^{\circ}$C, cotton caterpillar eggs developedto the last larval instar but were not able to go through the pupal stage. The lower developmentalthreshold temperatures and degree-days of egg, larva, pupa, and complete development were 13.4, 10.6,11.6, and 11.5"C and 55.3,251.5, 138.3, and 479.8 degree days, respectively. The hatching, pupation andemergence rates were higher at 25.0eC and 27.5"C compared with other temperatures. The survival ratefrom the hatched larva to adult was the highest at 27.5"C. The preoviposition and the adult longevity were11.5 and 30.6 days at 17.5"C and 1.5 and 9.2 days at 35.0$^{\circ}$C, respectively. The mean fecundity perfemales was greater at 25.0$^{\circ}$C and 27.5"C compared with other temperatures. Mean generation time indays (T) was shorter on higher temperature. Net reproductive rate per generation (R,) was the lowest atthe highest temperature as well as at the lowest, and it was 199.1 which was the highest at 27.5"C. Theintrinsic rate of natural increase (r,) was highest at 30.0$^{\circ}$C as 0.148. As a result, optimum ranges oftemperature for P. indica growth were between 25.0-32.5"C .emperature for P. indica growth were between 25.0-32.5"C .t;C .

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.195-201
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• 1986

This study was conducted to investigate the life history of Compsidia populnea which is major species of the stem-borers on Populus alba{\times}glandulosa$. Peak emergence of the adult of Compsidia populnea L. was around 10th${\sim}$l2nd of May in Chuncheon vicinities, having one generation a year in Korea. There was a preovipositional period of 10.7 days and a ovipositional period of 14.3.days. Mean adult longevity was 11 days for male and 13.8 days for female. Individual eggs were long oval with somewhat narrowed tip at one side and soft, 2.6mm in length, 0.8mm in diameter, and were laid singly under the U-shaped scars which were made by female before oviposition. Total number of scars per female averaged 56.6 ($8{\sim}135$) and eggs were found in 67.9 percent of the total scars. Egg period was $8{\sim}11$ days at $25^{\circ}C$ constant temperature and $7{\sim}14$ days in the field condition. Early young larvae stayed for $2{\sim}3$ weeks under the scars and then boring into the xylem, forming galls at this time. Size of the gall was 1.8cm($1.3{\sim}2.5$) in length, 1.6cm($1.0{\sim}2.2$) in diameter and the length of mine was everage 3.1cm. Fully grown larvae were developed around the early October and overwintered in the mines of galls. Pupation was done around the early of April. Pupal developmental period averaged 11 days($9{\sim}13$ days) at $25^{\circ}C$ constant temperature condition.