Studies on polymorphism of enzyme systems in populations of Apis florea F. (Hymenoptera: Apidae) from Chandigarh and foothills of Himachal Pradesh, North West India

Abstract

Biochemical characterization and enzyme polymorphism are useful tools in establishing intraspecific diversity in insect populations. The populations of Apis florea F. adult workers were selected from six varied topographic and climatic places of north western India including Chandigarh plain and foothills of Himachal Pradesh. These honey bees were analysed for proteome profile by SDS-Polyacrylamide gel electrophoresis (PAGE). Further four enzyme systems namely malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), esterase (EST) and hexokinase (HK) were analysed for enzyme polymorphism and isozymic variability in all the populations by running native PAGE and staining with specific substrate stains on the gels. Sixteen protein bands were reported in each population of A. florea using SDS PAGE and no difference was found in banding pattern of proteins of the populations studied. Enzymes stained on native PAGE from whole body homogenates revealed single isozymic form of ADH, two isozymic forms each of EST and MDH and three isozymic forms of HK in all the populations of A. florea collected from different study regions. There was significant difference in specific activity of enzymes from different regions but no polymorphism was found for the enzymes studied. Small changes in Rf values were found in the isozymes of the enzymes. The results suggest that none of these enzyme systems could be used as marker to differentiate the species at intraspecific level as the enzyme MDH, ADH, EST and HK did not exhibit polymorphism in A. florea from studied regions. In conclusion a single species of A. florea persisted throughout the area studied. However the slight changes in mobilities of individual bands and also changes in specific activity of enzymes reflect the adaptation ability of the bee according to climate variations.