B. Papp szerk.: Studia Botanica Hungarica 39. 2008 (Budapest, 2008)

Bauer, N., Lőkös, L.; Papp, B.: Distribution and habitats of Cardaminopsis petraea in Hungary

species' distribution. The biogeographical factors shown by the latest studies evidently confirmed the relict character of the species. Molecular genetic evidences have proven that the species might have survived the last glaciation in steppe-tundra habitats of the periglacial areas and also in montane réfugia in Central Europe. On the basis of analysing the genetic structure of the remnant populations of Cardaminopsis petraea in Pleistocene periglacial areas of Central Europe, CLAUSS and MlTCHELL-OLDS (2006) concluded that there are low but significant differences between the isolated populations because of limited gene-flow. These Central European populations are characterised by widespread polymorphism and higher genetic diversity than the North European populations developing separately. The higher genetic diversity observed in Central Europe may be explained by the periglacial development. The genetic variation is high between the populations developed in different geographic areas (VAN TREUREN etal 1997, SCHIERUP 1998, SAVOLAINEN et al 2000, CLAUSS et al 2002, ANSELL et al. 2007). There are significant differences between certain morphological features, i.e. the trichomes (KÄRKKÄINEN et al. 2004), the blooming season and floral display (RIHIMÄKI and SAVOLAINEN 2004, SANDRIG et al 2007), the isoenzyme places (JONSELL et al 1995), the micro-satellite (VAN TREUREN et al 1997,GAUDEULe£^/. 2007), the sequence alternation (SAVOLAINEN etal 2000, WRIGHT etal 2003), and nuclear and chloroplast-DNA diversity (ANSELL et al. 2007). On the basis of the nuclear and chloroplast-DNA diversity analysis of the European populations ANSELL et al (2007) assumed the existence of two refuge areas during the glaciation (on an unknown location between the Scandinavian and the Alpine ice-fields, and on one Central European location), and see evidences of post-glacial recolonisation that has taken place in two waves. DAVEY et al. (2006) justified the cold tolerance of Cardaminopsis petraea through experiments as well. The differences among the geographically isolated populations were measured based on ecological and physiological data, but concerning the cold tolerance, eco-typical differences were not found within the species. The sexual reproduction of the species is characterised by outside pollen mediation of insects, its productive system being incompatible with itself. Dispersion by rhizomes was also revealed, but the contribution of such clone ramets to the population structure is geographically different (CLAUSS and MlTCHEL-OLDS 2006).