Electrophoretic enzyme comparison of wild and laboratory tsetse fly populations of glossina pallidipes and G. Brevipalpis (diptera: glossinidae)
Abstract
An electrophoretic comparison of 11 randomly selected enzyme
systems was made between two laboratory colonies of Glossina pallidipes
and one of ~. brevipalpis with their corresponding ancestral wild
populations. The samples were compared with regard to the amount of
genetic variation within each population. The genetic variability in
each population was measured by calculating the proportion of
polymorphic loci(P), and the average heterozygosity per locus. Other
parameters considered for comparison were:- allele frequency data, the
number of alleles per locus and effective number of genotypes at each
locus. To quantify the extent to which the colony flies carried
electromorphs similar to those found in natural tsetse, the identity
statistics, (Nei, 1972) and the standard distance between field and
colony flies were calculated. As a partial test of the genetic
interpretation of the observed variations, the electrophoretic patterns
of the polymorphic loci were examined for their goodness of fit with
regard to expectations based on Hardy Weinberg equilibrium model.
Of the 11 enzyme systems, only nine were consistently scorable.
The important observations of these investigations are that the field
flies were genetically approximately the same as those of the laboratory
samples. There was no difference as regards the percentage of
polymorphic loci. The difference in allozyme frequencies were not
statistically significant. The identity values between field and
laboratory samples were high and genetic distances small, showing that
the laboratory stocks were still closely related to their ancestral wild
populations. It was concluded that colonization has had no significant
change on genetic variations within the colony flies.
Citation
DEGREE OF MASTER OF SCIENCE (ENTOMOLOGY)Publisher
University of Nairobi Faculty of Science. University of Nairobi