• 한국잠사곤충학회지
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• 제17권2호
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• pp.119-124
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• 1975

가잠의 휴면물질을 구명하기 위하여 비휴면성잠의 식도하신경구(SG)를 가각 적출, Grace씨 배양액을 사용하여 체외배양실험 하였다. 배양완료 후, 배양산물액에 대한 생물검정실험(Bioassay)결과, 휴면성잠의 SG 및 비휴면성잠의 SG는 화성에 각각 독립적으로 영향하는 질적으로 상이한 물질, 즉 휴면물질(Diapause Substance) 및 비휴면물질(Non-diapause Substance)을 분비하고 있음이 밝혀졌다. 잠난의 휴면성및 비휴면성의 결정은 이 양물질간의 질적인 차이에 기인하는 것으로 생각된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권2호
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• pp.107-111
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• 2005

Impact of microsporidian infection and season on reproductive potential of Bombyx mori L. was investigated in the laboratory. Microsporidian infection significantly (P<0.01) reduced fecundity and hatching and increased sterility and mortality of eggs. Among the microsporidia, Nosema sp. 2 infected silkworm produced eggs with least fecundity and hatching percent as well as highest dead and sterile eggs followed by Nosema sp. 1 and N. bombycis. Microsporidia, in general, significantly reduced fecundity and hatching percent of eggs and increased number of dead and sterile eggs in all the three seasons except N. bombycis in July - August (S3) and Nosema sp. 2 in January February (S1). Since, seed production is the anchor sheet of mulberry sericulture, coefficient of egg lying is considered as an important aspect and the industry quite often facing shortage of disease free layings. The present study indicates that B. mori is more susceptible to microsporidia during S2 followed by S3 and S1 and Nosema sp2. is most virulent followed by Nosema spl. and N. bombycis.

• 한국잠사곤충학회지
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• 제5권
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• pp.39-42
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• 1965

최청말기에 있어서 산란잠종을 인위적으로 진동을 일으켜 주면, 란내의 의잠은 란각을 벗어날 때, 두부를 내밀고 나와야 할 것인데, 진동으로 인하여 꺼꾸로 미부를 내밀고 나오게 된다. 이때 미부로 나오는 경우는 란각을 벗기지 못하고 의잠의 두뇌부를 씌워진채 있고 이 란각은 자기의 힘으로는 벗기지 못한다. 이러한 상태의 역출란의잠은 진동으로 인하여 나타나는 것인데 그 비율은 정상부화의 약 30％가 된다. 이 역출의잠을 사육하였드니 누에는 잘 자라지 못하고 죽는 누에도 많고 사육성적은 극히 불량하다. 따라서 결론적으로 산란잠종을 농가에 배부할 때는 최청초기에 하거나, 또는 최청말기에 있어서는 난을 진동시키기 않도록 하여야 한다.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.59-63
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• 2004

By using PAGE, a study was made on the nonspecific esterase spectra of female genital organs and eggs in Bombyx mori L. The expression of 11 esterase bands was detected during ontogenesis of races and inter-races hybrids kept in Bulgaria. The gene activity of 9 esterase loci was assumed. Esterases specific for the spectrum of diapausing eggs were observed. In two esterase zones, intra- and inter-breed polymorphism was found. Based on the same breed specific expression, the existence of correspondence between esterase bands from spectra of different silkworm tissues and organs was suggested. Stage-specific expression of esterases in female genital glands, indicative of differentiated gene activity during ontogenesis, was established.

• 한국잠사곤충학회지
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• 11호
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• pp.55-57
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• 1970

1. 교잡종의 냉장침산잠종 재냉장 적기는 침산 후 48∼72 시간 즉 2∼3일이다. 2. 원종의 냉장침산잠종 재냉장적기는 침산후 72시간 즉 3일이다. 3, 교잡종이나 원종을 막논하고 냉장침산잠종의 재냉장적기는 일언으르써 침산후 72시이라고 판단되며 입고방법은 중간온도 보호의 영향력이 있다고 판단된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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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.

• International Journal of Industrial Entomology and Biomaterials
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• 제5권2호
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• pp.205-211
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• 2002

Previously, genetic relationships among 321 silkworm races preserved in the Department of Sericulture and Entomology, NIAST, RDA were studied using six isozymes comprising 20 loci. As a part of additional studies, three additional isozymes with 7 loci [phos-phoglucomutase (PGM), glucose phosphate isomerase (GPI), malete dehydrogenase (MDH)] from hemolymphs, midgets, and eggs were employed to reevaluate the previous dendrogram (UPGMA method). Although the current study supported the recognition of the previously identified major groups, some minor changes were apparent among the selected 47 forms. The current study showed that the polymorphic loci of GPI from eggs and MDH from hemolymph appear to be responsible characters for generating a new major group in the genetic relationship. Interpreting the data with current additive isozymes may represent more robust genetic relatioships among 321 silkworm races preserved in Korea, until further evidence is available.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.73-78
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• 2004

The impact of low concentration fluoride on toxification was studied by treating $3^rd$ instar silkworm larvae of Qiufeng${\times}$Baiyu (Fluoride resistant strain) and Jinshong${\times}$Haoyue (Fluoride sensitive strain). The $5^th$ instar silkworm larvae of Zhenong-l, Shu-12, Qiufeng ${\times}$ Baiyu, Chunhua ${\times}$ Qhiushi, Jinshong and Haoyue were fed mulberry leaves treated with sodium fluoride at different concentrations to determine its effect on fecundity. Harmful effects of low concentration fluoride at early instars on growth, development and economic characters of Bombyx mori are related to its resistance. Harmful effect on resistant strain Qiufeng${\times}$Baiyu manifested on prolongation of instar duration of 15 and 6% in 70 ppm, where as the sensitive breed Jinshong${\times}$Haoyue manifested with 100% mortality in 50 ppm. The impact of low concentration fluoride on fecundity resulted in considerable increase in formed eggs (9%) and laid eggs (9%) in Zhenong-l and Shu-12 among treated population over control. The present observations emphasis that fluoride apart from exhibiting harmful effects on silkworm growth and development, however, its low concentration do playa vital role in inducing some positive effect on fecundity and cocoon traits.

• 한국잠사곤충학회지
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• 제14권2호
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• pp.113-123
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• 1972

춘추잠기를 통하여 잠기별로 성적이 좋은 항목과 여타항목 성적간의 관계를 보면 일정한 경향을 발견할 수가 없으므로 종합적인 고찰을 하기가 지극히 곤란하나 대략 다음과 같이 요약할 수 있겠다.(Table Omitted) (1) 월년잠종 냉장입고시의 배자 발육계제와 부화율 및 실용부화율간 에는 어떠한 경향을 발견할 수가 없다. 그러나 부화율이 좋지 못한 잠종은 부화율이 낮을 뿐만 아니라 상견수견량과 화용율도 낮다. 실용부화율이 좋지 못한 잠종은 부화율이 약간 낮은 경향이 있으나 상견수견량과 부화율은 평균치 이상이거나 평균치에 근사하다. 따라서 실용부화율은 누에의 건강과는 관계가 적다고 할 수 있겠다. (2) 오교율은 상견수견량과 화용율에 영향을 미치리라고 생각되며 오교율이 높아지면 원잠이나 원잠견의 혼입률이 높아지는 것이다. 그리고 오교율은 잠견제조에 속하는 문제이며 양잠의 양적 및 질적 생산에 영향을 미치는 요인이라고 하겠으나 여건에 따라서는 원종과 교잡종간에 현격한 차가 나타나지 않는 것이라고 생각된다. 또한 월년잠종과 불월년잠종간의 평균오교율차는 교잡원종의 순도에 기인한 것이라 생각된다. (3) 상견수견량이 적은 잠종은 화용율이 낮은 경향이 있으니 상견수견량과 화용율간에다 관계가 있다고 생각된다. (4) 견층비율이 낮은 잠종은 화용율이 낮아지는 경향이 있다고 하겠다. 따라서 견층비율은 잠품종적인 문제 이외에 잠작과도 유관하다고 생각된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제43권2호
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• pp.37-44
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• 2021

Mulberry silkworm is classified into uni, bi and multivoltine based on the frequency of diapause incidence. The variation in the incidence of diapause in bivoltine silkworm provides a unique opportunity to study the process of evolution of adaptive plasticity towards seasonal variations. The diapause expression in bivoltine silkworm is highly variable and is determined by environmental factors experienced by the maternal generation. Diapause in natural populations is functionally associated with the overwintering mechanism that facilitates survival in harsh winter conditions. In contrast, under standard commercial rearing conditions, the domesticated bivoltine silkworm is known to enter diapause in every generation. This paper presents a short review of the literature dealing with the role of temperature, photoperiod, diapause hormone and its receptor in diapause induction. Also, we briefly review the incidence of non-diapause eggs in bivoltine silkworm under controlled conditions.