Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Allozyme frequency changes in two inverse sequences of environments in Drosophila melanogaster | Génét. Sél. Evol. 1985 17 1 59-72 Allozyme frequency changes in two inverse sequences of environments in Drosophila melanogaster H. MERỌOT Laboratoứe de Génétique des Populations tour 42 Université Paris 7 2 place Jussieu F 75005 Paris Summary Six replicates of a Drosophila melanogaster population were confronted with 2 sequences of 3 different environments to wit 3 replicates with the environmental sequence E1-E2-E3 characterizing the Hl history and 3 replicates with the inverse sequence E3-E2-E1 characterizing the H3 history. The 6 replicates maintained in population cages were exposed to each environment for 5 discrete generations. Changes in allozyme frequencies at 4 loci were analysed to detect whether the changes depended upon the order of succession of the 3 environments. This was only the case for one locus Adh but not for Est-6 and Pgm and can be related to the sensitivity of the Adh locus to environmental diversity. For the last locus a-Gpdh the substantial heterogeneity between replicates within each history seems to be due to a hitchhiking effect. The diversity of the observed evolutionary profiles more important between loci for a same history than between the 2 histories for a same locus seems to point to a set of genetic interactions peculiar to each locus. Key-words Environmental diversity enzyme polymorphism Drosophila melanogaster partition of X2- Résumé Variations de frequences allozymiques dans deux series inverses d environnements chez Drosophila melanogaster Trois répliques d une population de Drosophila melanogaster ont été confrontees à une sequence de 3 environnements differents caractérisant 1 histoire Hl. Simultanément 3 autres répliques de cette population ont été confrontees à la sequence inverse des 3 envi-ronnements caractérisant 1 histoire H3. Les 6 répliques ont été gardées en cage à population 5 generations discretes par environnement. A 1 aide de la methode de decomposition du X2 les variations de frequences allozymiques à 4 locus
