Relacions entre diverses espècies de Saxifraga dels Pirineus i de les muntanyes Catalanídiques

Abstract

[EN]Our study concerns eight species of the section Pentadactyles, namely two (S. genesiana and S. vayredana) endemic of the Montseny-Guilleries massif, five (S. geranioides, S. moschata, S. intricata, S. pentadactylis and S. pubescens) growing in the Pyrenees, and one (S.fragilis) existing in both mountain ranges (Pyrenees and Catalanidic); as well as several natural hybrids between some of these taxa. In order to know the relationships among all them, we take in account vegetative and floral parameters, pollen and seed morphology and viability, nuclear DNA amount and chromosome numbers. The results show DNA content to be conclusive to differentiate all taxa and to detect hybrid populations. Pollen grains and seeds give also discriminative characters. As regards the distinction between S. geranioides and S. genesiana, the sole important character is the seed ornamentation, consisting of micropapillae in the first taxon, while of mixed micropapillae and macropapillae in S. genesiana. The chromosomal number is the same (2n = c. 44) in both taxa. Results suggest that S. genesiana derived from a S. geranioides population of Eastern Pyrenees.