BERRIGAN D, HERCUS M, DAGHER H, HOFFMANN A A.
School of Genetics and Human Variation, La Trobe University, Bundoora, Victoria 3083, Australia
J Insect Physiol. 1997 Apr;43(4):393-405. doi: 10.1016/s0022-1910(96)00108-4.
Lines of the fly Drosophila melanogaster were selected for increased knockdown resistance to heat (39 degrees C) in a long tube. One set of lines was selected following prior heat hardening (1 h at 37 degrees C) and another without hardening. Each set consisted of three replicate selection lines and three unselected controls. Lines were tested for correlated responses to selection, in order to define the nature of knockdown resistance. Selection had a large effect on knockdown resistance, but selected lines did not differ from controls for knockdown time in small vials, survival, or recovery time following exposure to heat. Selection with and without hardening influenced the hardening response in the long tube, but not in small vial assays of resistance. The hardened selection lines had decreased resistance to ethanol and a reduced dry weight, whereas the non-hardened lines did not show these changes. The same correlated responses were also evident in two generation experiments on unselected flies. Both sets of lines showed a reduction in activity when tested at 37 degrees C, but not at 25 degrees C. These results indicate that different measures of heat resistance are surprisingly unrelated, and suggest that subtle features of the selective environment influence responses and correlated responses to selection. Copyright 1997 Elsevier Science Ltd. All rights reserved
对黑腹果蝇品系进行了选择，以提高其在长管中对高温（39摄氏度）击倒抗性。一组品系是在预先热硬化（37摄氏度处理1小时）后进行选择的，另一组则没有进行硬化处理。每组包括三个重复的选择品系和三个未选择的对照。对品系进行了选择相关反应的测试，以确定击倒抗性的本质。选择对击倒抗性有很大影响，但在小瓶中，选择品系与对照在击倒时间、存活率或热暴露后的恢复时间方面没有差异。有硬化处理和没有硬化处理的选择对长管中的硬化反应有影响，但在小瓶抗性试验中没有影响。经过硬化处理的选择品系对乙醇的抗性降低，干重减少，而未硬化的品系没有出现这些变化。在对未选择果蝇进行的两代实验中，同样的相关反应也很明显。两组品系在37摄氏度测试时活性都降低，但在25摄氏度时没有。这些结果表明，不同的耐热性测量方法出人意料地不相关，并表明选择环境的细微特征会影响对选择的反应和相关反应。版权所有1997爱思唯尔科学有限公司。保留所有权利
