• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.117-121
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• 2004

The patterns of diapause-associated proteins of silkworm eggs were analyzed by two-dimensional (2-D) gel electrophoresis. Among the hundreds of spots on the 2-D gels, at least two proteins were considered to be associated with diapause. A protein, spot 4, with an approximate molecular weight of 38 kDa and pI 6.1 was observed in the HCI-treated, cold-treated, and diapause eggs, respectively. Spot 4 was undetectable in unfertilized eggs and non-diapause eggs at two days after oviposition, suggesting that this protein may be associated with the entrance to diapause. A protein, spot 11, with an approximate molecular weight of 21 kDa and pI of 61 was detected in the unfertilized, HCl-treated, and cold-treated eggs, respectively, after oviposition by normal moths. In diapausing eggs, a protein corresponding to spot 11 was observed in 3-, 5-, and 30-day-old eggs, while the protein was not detected one-day-old eggs. The protein corresponding to spot 11 was not detected in unfertilized and non-diapause eggs obtained from subesophabeal ganglion (SG)-extirpated moths either. Spot 11 was also considered to be a diapause specific protein, which occurred at only early embryonic stage under the control of diapause-downregulated gene.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.95-96
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• 2003

We investigated the proteins that are associated with initiation, maintenance, and termination of diapause in silkworm eggs by means of 2D-gel electrophoresis. 1. Materials : Bombyx mori: unfertilized eggs, diapause eggs, non-diapause eggs, cold-treated egges. 2. Methods: isoelectric focusing, SDS-PAGE, silver staining. (omitted)

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.149-153
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• 2002

Induction of non-diapause eggs and manifestation of quantitative characters were studied in different seasons by low temperature incubation of eggs of a low yielding diapause with coloured cocoons silkworm breed, RDI of Bombyx mori. Hundred percent of nandiapause eggs were induced when the egg incubation was carried out at 15$^{\circ}C$ followed by incubation initially at $25^{\circ}C$ and then at $15^{\circ}C$. The diapause-nondia-pause relation was found to be reversible. Analysis of variance study demonstrated significant variation in all the quantitative characters whereas significant variation due to different incubation treatments was observed for larval span, fifth instar larval span, cocoon yield/10,000 larvae by weight, cocoon weight, cocoon shell weight, and cocoon shell ratio. study on hybrid vigour skewed significant heterosis over mid parent value for four economic characters viz., cocoon weight, cocoon shell weight, cocoon shell ratio and filament length in a Fl hybrid between RD1 with diapause eggs and Japanese type bivoltine $NB_{4} D_{2}$.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.24-30
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• 1985

The effect of some organic solvents on interrupting diapause of Bombyx mori eggs was examined to provide a clue to the mechanism of diapause initiation. Methyl alcohol and benzene proved to be efficient in developing the prospective diapause eggs upto the stage of hatching or body pigmentation of the embryos. On the other hand, most of the eggs soaked in chloroform and mixture solution of chloroform-methyl alcohol (2:1) died in the early embryonic developmental stage with yellow or red brown colours, and the egg weights decreased upto ca. 40% of the original weight 8 days after the treatments. Methyl alcohol treatment for 2, 5 and 10 min to the 5hr-old-eggs led to empergence of the larvae, with high incidence (70∼80%) in the race of Kumchu X Chonghwa and with low indidence (1∼4%) in Daezo. The effect of same treatment to 20hr old eggs decreased to ca. 10% in the emergence of larvae in Kumchn X Chonghwa and increased to 20∼30% in Daezo, while the effect disappeared shortly after the diapause initiation (48hr-old-eggs). Considering the high dependency upon the egg age of the sensitivity to solvents, it was supposed that initiation and termination of diapause may be controlled by different mechanism. It was also suspected that the solvents exert their effect on the permeability of the eggshell.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.73-76
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• 2004

The rate of oxygen consumption of the silkworm eggs was measured to set up the barometer for measuring the effect of egg chilling on diapause termination. In diapause eggs, $O_2$ uptake showed a maximum of 79.2 ${mu}ell$/mg eggs/hr, at one day after oviposition and then gradually decreased to 2.2${mu}ell$/mg eggs/hr at 9days. The rates of oxygen uptake of eggs raised immediately after HCl-treatment and reached to a maximal level of 484.5 ${mu}ell$/mg eggs/hr in 9-day-old eggs, which corresponds to 220 fold that of diapause eggs, and the hatching ability was also over 50％. In order to break diapause, eggs incubated at $25^{\circ}C$ for 30 days after oviposition had to be kept at least for 45 days at 5$^{\circ}C$, but chilled eggs for 90 days or longer hatched at 10 days as normal hatching periods. We also investigate periods which the value of $O_2$ uptake of eggs chilled during 15 to 120 days at 5$^{\circ}C$ reached at 200 ${mu}ell$/mg eggs/hr. As a result of that, $O_2$ uptake of eggs chilled during 15 to 45days were not reached at 200 ${mu}ell$/mg eggs/hr and longer the chilling durations are, the higher the rate of $O_2$ uptake is and the longer the chilling durations are, the shorter the periods up to hatching is. And also, hatch-ability increased rapidly as $O_2$ uptake reaches over 20/eggs/hr.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.258-264
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• 1991

Studies were carried out to investigate effects of temperature and photoperiod on diapause induction and of juvenile hormone III and 20-hydroxyecdysone treatment on diapausing adults of the alder leaf beetle, Agelastica coerulea Baly(Chrγsomelidae: Coleoptera). Its life cycle and ovarian development in adults were also observed. The beetle had one year life cycle with egg, larval, pupal and adult periods being 7-10, 19-21, 14-15 days and about 10 months, r respectively. All adults showed a diapause syndrome when the larvae were reared at $20^{\circ}C$ or $25^{\circ}C$ in combination of photoperiods of 16L/8D, 12L/12D, or 8L/16D. Their ovarioles did not s show any development of vitellogenesis before or during diapause and even when exposed at $15^{\circ}C$ after overwintering. When diapausing adults were treated with JH III they resumed feeding and laid several eggs and broke diapause condition temporally. But diapausing adults treated with 20-hydroxyecdysone did not show any response.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.159-162
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• 2012

The Chinese windmill butterfly, Atrophaneura alcinous, is an important butterfly for exhibition in butterfly garden. The objective of this study was to determine the effect of temperature on A. alcinous in the laboratory. Development of A. alcinous reared on leaves of Aristolochia contorta was investigated at five constant the laboratory condition (20, 22.5, 25, 27.5 and $30^{\circ}C$) and at relative humidity of 60% with a photoperiod of 14:10 (L:D). Temperatures have been suggested as an important determinant of developmental rate, lifespan and mortality in invertebrates. As the temperature increased, the length of the developmental period gradually decreased. The developmental time (pupation) from egg hatching to pupation was respectively 25.8, 23.6, 19.6, 15.5, and 12.9 days at the temperatures of 20, 22.5, 25, 27.5 and $30^{\circ}C$. And pupation was respectively 40.0, 30.0, 63.4, 50.0, 23.3% at the temperatures of 20, 22.5, 25, 27.5 and $30^{\circ}C$. The developmental threshold temperature estimated for egg-to-pupae was 10.8, with a thermal constant of 230.4 degree-days. Therefore, the optimal developmental temperature for A. alninous was determined to be $25^{\circ}C$. To compare the effects of the total duration of chilling on the termination of diapause, larvae were subjected to a temperature of $8^{\circ}C$ from 60 to 120 days. The rate of termination of diapause was significantly higher at 60 days compared to other incubation period.

• International Journal of Industrial Entomology and Biomaterials
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• v.24 no.2
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• pp.69-74
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• 2012

Tropical tasar silkworm Antheraea mylitta Drury experiences extreme temperature stress conditions during its life cycle particularly during diapauses and first crop. The present study witnessed the impact of high temperature on some biochemical profiles and egg production (fecundity) of semi-domesticated Daba and Shorea robusta (Sal) based wild ecorace Laria during seed cocoon (pupa) preservation. Cocoons of Daba and Laria were treated with high temperature at $40^{\circ}C$ for 10 days in a BOD incubator. The protein profile and carbohydrate content in the hemolymph and fat body and total haemocyte count (THC) in the hemolymph of pupa were investigated. Further, the fecundity and fertility of egg was assessed. Significant increase in the protein concentration was observed in the hemolymph with reduction in the fat body (p<0.05). The difference in protein concentration was highly significant between the semidomesticated Daba and wild ecorace Laria (p<0.05). High pupal mortality (20%) and reduced fecundity (10-15%) in Daba was noticed compared to wild Laria. Also an increased THC (>28000) was recorded in Laria. The study infers the potentials of wild ecoraces in sustaining the extreme temperature conditions and need of adopting suitable package of practices for the preservation of diapause seed cocoons during extreme summer conditions. There is possibility to introgression thermal stress resistant traits in the semi-domesticated races of tasar silkworm by resorting to conventional breeding plans with wild races and keeping the thermal stress induced response as markers.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.91-95
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• 2005

This study was conducted to investigate the morphological characteristics, overwintering sites and behavior for each stage of Oligota kashmirica benefica (Coleoptera: Sthphylinidae). Egg was oval type, yellow, 0.3 mm size. Larva exuviated 3 times and the last (3rd) instar, length 1.6 mm, wide 0.4 mm, became dermata pupa in soil. Adult was lightish dark-brown, and coriaceous forewing covered a half of abdomen. O. kashmirica benefca mainly overwinters with adult at Japanese cedar (Cryptomeria japonica) windbreaks of orchards, but it did not diapause in greenhouse during winter.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.274-281
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• 2020

This study aimed to investigate the autumn spawning by bitterling (A. rhombeus) inside mussel (Unio douglasiae) and the adaptation characteristics at the Bongseocheon Stream of Mankyeonggang River. The survey was carried out between August 2015 and July 2016. The spawning season was from September to November, and 17-75 (36.2 ± 16.44) eggs were found from mature females. During the survey period, 476 mussels were collected, 129 (27.1%) of spawned A. rhombeus. Mussels that spawned eggs, embryos, and larva of A. rhombeus (46.3 ± 4.55 mm, n = 129) were larger than than those that did not spawn (42.6 ± 8.51 mm, n = 347). The appearance frequency of A. rhombeus larva before and after the formation of lens was 99.8% (n = 597) vs. 0.2% (n = 1) from October 2015 to March 2016, 25.6% (n = 23) vs. 74.4% (n = 67) in April 2016, 0% (n = 0) vs. 100% (n = 40) on May 2016. The number of eggs, embryos, and larvae of A. rhombeus inside the mussels were 1-18 (5.6 ± 3.81). The number and appearance frequency of A. rhombeus eggs, embryos, and larvae inside the mussel according to mussel gill demibranchs position were 1 (0.01 ± 0.09, n = 1) and 0.78% in the left outer demibranch, 1-18 (2.33 ± 3.31, n = 63) and 48.84% in the left inner demibranch, 1-15 (2.97 ± 3.79, n = 76) and 58.91% in the right inner demibransh, and 1-12 (0.33 ± 1.71, n = 7) and 5.43% in the right outer demibransh. The highest frequency of the developmental position of eggs, embryos, and larvae occurred 71.8% (n = 445) in lower part 3 (L3) before formation lens and 94.4% (n = 102) in L3 after formation lens, indicating that L3 was dominating position for eggs, embryos, and larvae. More eggs, embryos, and larvae of A. rhombeus were found more often in the inner demibranshs than outer demibranchs. Since A. rhombeus is a species that spawn in the autumn and thus avoids the competition with interspecific and glochidia. However, they have to spend the winter in low water temperature. Consequently, we assume that A. rhombeus have evolved toward embryonic diapause under the low water temperature before the formation of lens and spawning inside the supracranchial cavity to save the transit energy from the water space to the suprabranchial cavity after the achieving movement ability with the formation of lens.