Impact of Fungus on Egg Shell of Tropical Tasar Silk Worm, Antheraea mylitta: An Ultra-structural Approach

  • Published : 2009.06.30

Abstract

The egg shell of the tropical tasar silkworm, Antheraea mylitta is formed from the substances secreted by the follicular epithelium during the late vitellogenic stage. TEM study reveals the inner travecular and outer lamellar layer of chorion. The travecular layer is composed of the innermost wax layer, inner and outer chorionic layer. The inner and outer chorionic layers are connected to each other by vertical pillers forming of cavities. The lamellar layer is perforated by the aeropyles. SEM study reveals the differentiation of an anterior surface of the egg shell into four zones-micropylar, edge, aeropyles crown and disc zone. In the mycosis infected eggs the aeropyles and egg-shell surface are fully packed with the hyphae of the fungus, Aspergillus sydowi blocking of plastron respiration and causing the death of developing embryo so that mycosis infected eggs become sterile.

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References

  1. Andrew RJ, Tembhare DB (1995) Ultrastructral post-oviposition changes in the egg chorion of the dragonfly Zyxomma petiolatum Rambur (Odonata: Libellulidae) Int. J Inseet Morphol & Embryol 24, 235-238 https://doi.org/10.1016/0020-7322(94)00019-M
  2. Andrew RJ, Tembhare DB (1996) Surface ultrastructure of the egg chorion of Bradinopyga geminata (Rambur) and Rhyothemis variegata (Linn.) (Anisoptera: Libellulidae). Fraseria (N.S) 3, 1-5
  3. Bells XP, Cassier SC, Pascual N, Andrew M, Rosso Y, Piulachs MD (1993) Induction of choriogenesis by 20-hydroxyecdysone in the German cockroach. Tissue cell 25, 195-206 https://doi.org/10.1016/0040-8166(93)90019-H
  4. Blau HM, Kafatos FC (1978) Secretory kinetics in the follicular cell of silk moths during egg shell formation. J Cell Biol 78, 131-151 https://doi.org/10.1083/jcb.78.1.131
  5. Jolly MS, Sen SK, Sonwalkar TN, Prasad GK (1979) Non mulberry silk F.A.O. Aqric Service Bull 29, 1-179
  6. Hinton HE (1969) Respiratory system of the insect egg shells, Ann Rev Ent 14, 343-368 https://doi.org/10.1146/annurev.en.14.010169.002015
  7. Kafatos FC, Regier JC, Mazur GD, Nadel MR, Blau HM, Petri WH, Gelinas RE, Moore PB, Paul M, Fstratiadis, Vournakis AEJ, Goldsmith MR, Hun-sley JB Baker N, Nardi J, Koehler AM (1977) The eggshell of insects: differentiation specific proteins and the control of their synthesis and accumulation during development; in Results and problems in Cell Differentiation. Beerman,W. (ed.), pp. 8, 45-145, Sprinqer Verlag, Berlin
  8. Margaritis LH (1985) Structure and Physiology of the eggshell;in comprehensive insect physiology, biochemistry and pharmacology. Kerkut, GA and Gilbert L (eds.) pp. 1, 154-230
  9. Mazur GD, Regier JC, Kafatos FC (1980) The silkmoth chorion:morphogenesis of surface structures and it's relation to synthesis of specific proteins. Devel Biol 76, 305-321 https://doi.org/10.1016/0012-1606(80)90381-4
  10. Mazur GD, Regier JC, Kafatos FC (1982) Order and defects in the silkmoth chorion. A biological analogue of a cholesteric liquid crystals. in insect ultrastructure. Akai, H. and King R (eds.), Plenum Press, New York
  11. Moschonas N (1982) Evolutionary comparison of structural and regulatory chorion genes in two wild-type silkmoth species, Ph. D. Thesis Athens University
  12. Pascual N, Cerda X, Benito B, Tomas T, Divlachs MD, Belles X (1990) Ovarian ecdysteroid levels and basal oocyte development during maturation in the cockroach Blattella germanica (L) J Insect Physiol 38, 339-346 https://doi.org/10.1016/0022-1910(92)90058-L
  13. Paul M, Kafatos FC (1975) Specific protein synthesis in cellular differentiation II. The program of protein synthetic changes during chorion formation by silkmoth follicles and its implementation in organ culture. Dev Biol 42, 141-159 https://doi.org/10.1016/0012-1606(75)90320-6
  14. Regier JC, Kafatos FC (1985) Molecular aspects of chorion formation; in comprehensive insect physiology, biochemistry and pharmacology. Kerkut GA, and Gilbert L (eds.), pp. 1, 113-151 Pergamon Press, Oxford
  15. Regier JC, Mazur GD, Kafatos FC, Paul M (1982) Morphogenesis of silkmoth chorion: Initial frame-work formation and it's relation to synthesis of specific proteins. Dev Biol 92, 159-174 https://doi.org/10.1016/0012-1606(82)90160-9