Comparing different measures of heat resistance in selected lines of Drosophila melanogaster

Abstract

Lines of the fly Drosophila melanogaster were selected for increased knockdown resistance to heat (39°C) in a long tube. One set of lines was selected following prior heat hardening (1 h at 37°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 bad 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 t..