Intraspecific Genetic Variation Among Populations Of Kenyan African Violet, Saintpaulia Rupicola B. L. Burtt: A Molecular Approach
Abstract
Saintpaulia rupicola B. L Burtt (Gesneriaceae) is one of the African Violet species
under high threat of extinction from its habitat. It is endemic to coastal Kenya where
it occurs in Kilifi and Kwale districts in four distinct populations. The Cha Simba and
Mwarakaya populations contain plants that correspond to the typical Saintpaulia
rupicola. However, the other two populations. Kacharoroni and Mwache consist of
plants which are morphologically different, and which may qualify to be treated as
separate species, Saintpaulia sp. nov.
In order to design a conservation plan for this species, an insight in the genetic
diversity among these populations is required. Furthermore, a study at the molecular
level could help to clarify the taxonomic position of Saintpaulia sp. nov. with regard
to S. rupicola and other taxa in the genus Saintpaulia.
The Internal Transcribed Spacer region (ITS) of the nuclear ribosomal DNA was
analyzed as a genetic marker to determine the genetic variation among these
populations. DNA sequencing of this region revealed its conserved nature, with only
four (0.63 % of the whole region) base substitutions among the four populations. Low
genetic distances (between 0.0000 to 0.0048) were. observed among these populations,
indicating that the four are closely related, the most closely related being Kacharoroni
and Mwache populations (0.0016).
Cladistic analysis using Geneworks Release 2.3 and PHYLIP analysis programs
generated a total of five phylogenetic trees which cluster Mwarakaya with Cha Simba
and Kacharoroni with Mwache.
Citation
Master of Science in BotanyPublisher
University of Nairobi School of Biological Sciences