Saxifraga paniculata Mill. is an amphi‐atlantic species that is widely distributed in the Alps but also occurs with disjunct populations in central Europe. These isolated populations are considered to be glacial relicts. In the study presented here, we analysed the genetic variation within and between populations of Saxifraga paniculata in central Europe to test whether the molecular data give evidence for the supposed relict endemism. We used RAPD analysis and the analysis of molecular variance (AMOVA) technique to investigate 30 populations of Saxifraga paniculata from different locations in central Europe and adjacent geographical areas. In the RAPD analysis, 319 fragments could be amplified of which 91.2% were polymorphic. The percentage of polymorphic bands within populations correlated significantly with population size, indicating a higher level of inbreeding in small populations. AMOVA revealed 43.60% of the variation within populations, only 15.45% between populations within locations, and 40.95% between locations. Genetic distance between locations (ΦST) correlated significantly with the geographical distance between locations, giving evidence for geographical isolation. In an UPGMA cluster analysis, based on RAPD data, the populations were grouped together according to their location. The results exhibit a strong genetic differentiation which is obviously due to genetic drift in the isolated populations. Our study therefore gives evidence for glacial relict endemism of Saxifraga paniculata in central Europe. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 80, 11–21.

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Management practices like mowing or grazing have a large impact on grassland species. Due to its evolutionary significance, the interaction between the flowering time of plants and land use is of special interest. Asynchronous flowering restricts gene flow between populations and promotes, as a consequence, their differentiation. We selected 12 populations across southern central Europe to study the impact of mowing and grazing on seasonal and genetic differentiation in the grassland species Scabiosa columbaria. We conducted a common garden experiment to analyse floral display between populations and applied molecular markers to assess genetic diversity and genetic differentiation between populations. We demonstrated explicitly that flowering time and genetic differentiation are linked with the type of land use. Populations from mown habitats flowered significantly earlier than populations from grazed sites. Furthermore, genetic differentiation was stronger between populations from sites of different land use than between populations from far away geographic regions. The results of this study indicate that populations of S. columbaria are seasonally adapted to mowing and grazing. Land use is, therefore, an important factor for evolution in grassland species, which promotes the development of seasonal ecotypes and clearly affects intraspecific variation.

Areas of abandoned agricultural fields are globally increasing and are also common features in the Cape Lowlands of South Africa. Previous restoration attempts in degraded West Coast renosterveld, a Mediterranean-climate shrubland, have attained limited success and therefore novel approaches are needed for this area. The study reports on two restoration experiments, designed to re-introduce key plant functional types back into this critically endangered habitat. The first experiment concentrated on a common pioneer species in renosterveld vegetation, Otholobium hirtum. Although in vitro experiments showed a significantly elevated germination response after scarification, in vivo experiments failed to produce establishment in an abandoned field. The second restoration experiment focused on bush clumps, a sub-type of renosterveld vegetation that is characterized by broad-leaved shrubs with fleshy birddispersed diaspores. The effect of artificial bird perches and their potential to enhance diaspore dispersal by frugivorous birds in two abandoned field communities was tested. Results showed a significant increase in seed dispersal at artificial perch sites. However, in the next fruiting season, and after perch removal, seed germination and establishment in abandoned fields was not successful. The experiments revealed that restoration using earlysuccession species and natural dispersal vectors appear not to produce demonstrable benefits, despite their promising potential and pre-testing of effectiveness. Before launching large-scale restoration programs in abandoned fields of renosterveld, preliminary studies in-field are strongly recommended.

The spatial genetic structure as well as the occurrence of single genotypes revealed in this study suggests both clonal and sexual propagation and repeated seedling recruitment in established populations of S. herbacea and is thus suggestive of a relaxed phalanx strategy.

The molecular biogeography of the disjunctly distributed and morphologically highly variable species Saxifraga paniculata Mill. was analysed using amplified fragment length polymorphism (AFLP) and chloroplast microsatellites. The study comprised 77 samples from mountain regions in Europe and North America throughout the complete range of distribution. AFLP data revealed clear genetic differentiation between samples from the Arctic, the Caucasus, and the eastern European mountains. Samples from the Alps were divided into two groups. One group clustered with the samples from central Europe and the Pyrenees, whereas another group with individuals from southern Norway. AFLP diversity was lowest in the Arctic and highest in the Alps. Chloroplast microsatellite analysis revealed eight haplotypes but no unequivocal phylogeographical pattern. However, haplotype diversity was highest in the Alps and central Europe whereas, in the Arctic, only few widespread haplotypes could be found. The results indicate in situ survival of S. paniculata in the Caucasus, the eastern European mountains, and the Alps. The Arctic has presumably been colonized postglacially from North American refugia south of the ice shield. Southern Norway and the Pyrenees have most likely been colonized from two phylogeographically different groups in the Alps. The origin of the central European samples remains ambiguous. In situ survival seems to be as possible as several postglacial recolonization events from the Alps. The obtained molecular data clearly support the subdivision of S. paniculata into three subspecies: ssp. cartilaginea from the Caucasus, ssp. laestadii from northern Norway, Iceland, and North America, and ssp. paniculata from the other geographical regions. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 385–398.

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