[Chronology of embryonic development of the strain "Espiguette" with or without diapause in Locusta migratoria Linnaeus (Orthoptera: Acrididae)].
Examination of the eggs taken every 24 hours after laying enabled us to study the chronology of the embryonic development of the "Espiguette" strain of L. migratoria L. This strain is heterogeneous since the development at 27 degrees C is with or without diapause according to the eggs. The eggs that will later on enter diapause present a slower development than that of the other eggs. The slowdown of development becomes more pronounced until the entering into diapause. After the period of diapause, the development of univoltin eggs at 27 degrees C resumes very slowly since the katatrepsis is accomplished in three days, whereas the katatrepsis of the eggs without diapause lasts only 24 hours. As for the eggs which do not express diapause, the embryos complete both anatrepsis and katatrepsis at the same speed. Their morphology changes at the same speed as well until the stage VII. However, the end of development is accomplished slowly until the egg hatching. Thus two critical moments can be defined: the first one at the beginning of anatrepsis concerns the eggs that will enter diapause, and the second one which takes place at stage VII, i.e. after the dorsal closure of the embryo, and concerns the eggs that will avoid diapause. These critical moments must probably correspond to particular states of the embryonic metabolism, which would later on tend to become at a lower level.
Harrat
Abboud
A
Laboratoire de biosystématique et écologie des arthropodes, faculté des sciences de la nature et de la vie, département de biologie animale, Université Mentouri/Constantine, route d'Aïn-El-Bey, 25 000 Constantine, Algérie. abboud52@yahoo.fr
Petit
Daniel
D
D000818:Animals; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology / Q000502:physiology*; D047108:Embryonic Development / Q000502:physiology*; D048188:Locusta migratoria / Q000033:anatomy & histology / Q000254:growth & development* / Q000502:physiology; D008675:Metamorphosis, Biological / Q000502:physiology; D010063:Ovum / Q000254:growth & development; D013997:Time Factors