Attempted discrimination of Myzus persicae and Myzus nicotianae (Homoptera : Aphididae) by random amplified polymorphic DNA polymerase chain reaction technique

Random amplified polymorphic DNA (RAPD) analysis was applied to several clones of the Myzus persicae (Sulzer) group from Greece to assess genetic markers that could distinguish the tobacco feeding clones from those feeding on other host plants and to define the taxonomic status of Myzus nicotianae Blackman. Furthermore, 6 aphid species mere used as outgroups in the analysis. Using morphometric analysis; based on multivariable techniques and Blackman key, clones isolated from tobacco have been identified as M. nicotianae. Sixty-four decamer random primers were used to assay polymorphism between species and clones. Although the pl primers screened could discriminate species beyond the M persicae group. all clones belonging to the M persicae group had almost identical banding patterns. We failed to detect any consistent differences in RAPD Landing pattern between clones from tobacco and those from other plants collected from Greece, casting doubt on whether M. nicotianae should be regarded as a distinct species. However, a single-band difference, significantly associated with host plant. was revealed using primer OPA-18 and this supports is the idea that there is a host race adapted on tobacco. In addition, using primer BAM, a single band difference was observed between green and red clones feeding on tobacco