POPULATION SUBSTRUCTURE IN ALKANNA-ORIENTALIS (BORAGINACEAE) IN THE SINAI DESERT, IN RELATION TO ITS POLLINATOR BEHAVIOR

Subpopulation genetic structure was studied in a population of the sho rt-lived perennial plant Alkanna orientalis from the Sinai Desert, Egy pt. The population investigated was subdivided for sampling into four subpopulations, which were located within three steep-sided wadis and a central plain area. Results from previous studies suggested that bee pollinator behaviour was Likely to cause Limited gene dispersal withi n the population and that subpopulations might have diverged from each other genetically. Seven RAPD primers were used to detect polymorphis ms in the population. Differences between subpopulations in fragment f requency were found for several of the 45 polymorphic RAPD fragments s cored. Population subdivision was evident from cluster analysis, and a n analysis of genetic distances showed that there was significant gene tic differentiation between all subpopulations. Nevertheless, more ext ensive gene flow appears to take place within the population than was expected, as demonstrated by a higher level of genetic similarity betw een subpopulations from two of the narrow wadis and the interconnectin g plain. It is suggested that seed transport mediated by periodic flas h floods is responsible for this pattern.