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Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh Original cung cấp cho các bạn kiến thức về sinh học đề tài:Phenotypic plasticity of body pigmentation in Drosophila: Resistance to heat and cold stress in Drosophila melanogaster: intra and inter population variation in relation to climate. | 497 Genet Sei Evol 1997 29 497-510 c Elsevier Inra Original article Resistance to heat and cold stress in Drosophila melanogaster intra and inter population variation in relation to climate D Guerra1 s Cavicchi1 RA Krebs2 V Loeschcke3 1 Dipartimento di Biologia evoluzionistica sperimentale Università di Bologna via Selmi 3 40126-Bologna Italy 2 Department of Organismal Biology and Anatomy The University of Chicago 1027 East 57th street Chicago IL 60637 USA 3 Department of Ecology and Genetics University of Aarhus Ny Munkegade Bldg 540 DK - 8000 Aarhus c Denmark Received 13 June 1996 accepted 9 June 1997 Summary - Genetic variation for resistance to high and low temperature stress and wing size was examined within and among four Drosophila melanogaster populations from temperate Denmark and Italy and subtropical areas Canary Islands and Mali . The temperature of induction of the heat shock response was examined by conditioning flies to different high temperatures in the range 34 to 40 c prior to exposing them to heat shock 41.5 c for 0.5 h . Stress resistance appeared to be related to climate populations from warm regions were the most heat tolerant and those from cold regions were the most cold tolerant. This trend suggests that natural selection in the wild at non-extreme temperature can lead to a correlated response in tolerance to extreme temperature. Wing size varied significantly and generally was larger for flies from more northerly populations. Populations varied genetically in all traits measured. Among traits a positive correlation was present between heat-shock resistance with conditioning and resistance to cold and the correlation was suggestive between heat-shock resistance with and without a conditioning treatment but no correlation was indicated between cold resistance and heat resistance of non-conditioned individuals. Wing size was not correlated with any stress type. The results suggest that different groups of genes are involved in the resistance
