RAPD variation in populations of Cardamine lilacina (Brassicaceae)

Abstract

Random amplified polymorphic DNA (RAPD) analysis of DNA samples clearly distinguished between Cardantine hirsuta L. and two variants of Cardamine lilacina Hook. found in Australia. Cardarnine hirsuta, a recent immigrant, was less variable than C. lilacina, robust alpine snow-patch variant (C. lilacina-RASPV), which is an endemic plant that grows in three distinct regions in the Kosciusko alpine area and C. lilacina, intermedia variant (C. lilacina-IV), which is an endemic plant that is widespread in the same area. Comparison of RAPDs showed that, in the populations of C. lilacina-RASPV, some plants found near each other were closely related, but there was no detectable largerscale population structure. It is most likely that the present populations of C. lilacina-RASPV are relics of a single larger heterogeneous population. Cardarnine lilacina-RASPV is the only known natural host of turnip yellow mosaic tymovirus in Australia. Although in this study RAPD analysis did not indicate whether the host plant variation is influencing the variability of populations of this virus it did provide an understanding of the genetic relationships in these populations of C. lilacina.