Genetic variability of alcohol dehydrogenase among Australian Drosophila species: correlation of ADH biochemical phenotype with ethanol resource utilization

Abstract

Alcohol dehydrogenase (ADH) activities, electrophoretic phenotypes, and the extent of ethanol resource utilization are compared for three groups of species distinguishable on ecological criteria: 1) the cosmopolitan species D. melanogaster, a frequent inhabitant of wineries; 2) fruit-baited species of the typically Australian subgenus Scaptodrosophila: D. lativittata, D. nitidithorax and D. howensis; and 3) Scaptodrosophila species not attracted to fermented-fruit baits being collected by sweeping in temperate rain forests (D. inornata, D. collessi) or from Hibiscus flowers (D. hibisci). D. melanogaster showed the highest levels of ADH activity and an electrophoretic polymorphism with two active allelic forms, while group 2) species showed intermediate ADH activities and polymorphisms, which were consistent with "high activity" and "low activity" allelic forms in natural populations of these species, and group 3) species showed only "low activity" forms. Ethanol resource utilization follows the same sequence, being 1 greater than 2 greater than 3 (D. howensis and D. collessi were not tested). Therefore the species considered show an association of ADH biochemical phenotype, laboratory ethanol utilization, and resources utilized.