ADAPTIVE SIGNIFICANCE OF AMYLASE POLYMORPHISM IN DROSOPHILA .8. EFFECT OF CARBOHYDRATE DIETARY-COMPONENTS ON ALPHA-AMYLASE ACTIVITY AND AMY-ELECTROMORPH FREQUENCY IN DROSOPHILA-BUSCKII

Laboratory populations of D. busckii flies were kept for one generatio n on media containing different carbohydrate sources (maltose and rice , potato or maize starch). The flies maintained on standard potato med ium served as a control. Progeny were analyzed for alpha-amylase activ ity and Amy-electromorph frequencies. Spectrophotometrically assayed a mylase activity was highest in the flies cultured on potato starch med ium and lowest in specimens kept on maltose. Carbohydrate source in so me substrates affected both frequencies of Amy-alleles and Amy-genotyp es. Phenotypic differences at a biochemical level, i.e. in alpha-amyla se activity, might be connected to Amy-structural gene polymorphism in the examined Drosophila species.