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

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

On the basis of karyological analyses of Cardaminopsis petraea populations the species is diploid (2n - 16) (HEDBERG and HEDBERG 1961, POLATSCHEK 1966, BÜRDET 1967), however, tetraploid populations were also documented (In - 4x = 32) (POLATSCHEK 1966, DART et al 2004). DART etal. (2004) mention the hybrid (allopolyploid) origin or the gene alternation following the poliploidisation, authors also demonstrate the dynamic feature of the polyploid genom. The allopolyploid origin of the Austrian tetraploid populations in the Alps (the closest populations to the species' occurrences in Hungary) can be explained by the hybridisation with Arabis arenosa (= Cardaminopsis arenosa) (MATSCHINGER and KOCH 2003, DART etal 2004). Mygind in LINNÉ (1774,1784), later HAYEK (1908) on the basis of occurrences in eastern Austria probably consider this species ("fol bispidis..,", "alsó szárlevelei lehetnek fogazottak..." [its lower stem-leaves may be dentate], etc.) as one broadly interpreted species (called Arabis bispida Myg. and/or Cardaminopsis bispida (Myg.) Hay.). So far, individuals of the Hungarian stands have not been analysed genetically, but morphologically they can be identified with these descriptions. Regarding the habitat preferences of Cardaminopsis petraea it is generally discussed that it occurs on habitats characterised by low competition, sometimes with moderate disturbances (ERICSON and MASCHER 1978, HEMP 1996, CERNY etal 2006), and it also grows as a pioneer-like primary phanerogam in coastal areas. It was reported from various bedrocks (limestone, dolomite, basalt, anorthosite, dolerite, granite, serpentine, gabbro, sandstone, sand) (MEUSEL 1939, HOHENESTER I960, HEGI I960, SPENCE 1970, ERICSON and MASCHER 1978). The Central European populations, however, are found on calcareous or basaltic bedrocks and outcrops (MEUSEL 1939, HOHENESTER I960, HEGI I960, SPENCE 1970, MlLBRANDT 1976, BORHIDI 1995, ELLENBERG 1996). Its Hungarian stands grow on dolomite in the Keszthely Mts, and on basalt on Csobánc Hill in the Balaton Uplands (FEKETE 1964). ZÓLYOMI (1942) lists Cardaminopsis petraea among the species of the Middle Danube flora boundary (confined to the southwestern part of Osmátra, Transdanubian Mts). Most references agree on the basic ecological requirements of Cardaminopsis petraea. BORHIDI (1995) mentions it as a drought-resistant species that thrives on places of low nutrition content. A number of references deal with its light requirements, and consider it a photophilous species yet