Populations of Pilosella species in ruderal habitats in the city of Prague

František Krahulec, Anna Krahulcová, Tomáš Urfus, Jan Doležal
2020 Preslia (Praha)  
Populations of Pilosella species in ruderal habitats in the city of Prague: consequences of the spread of P. aurantiaca and P. rothiana Populace druhů rodu Pilosella na ruderálních stanovištích v Praze: následky expanze P. aurantiaca a P. rothiana Populations of Pilosella species in ruderal habitats in the city of Prague: consequences of the spread of P. aurantiaca and P. rothiana. -Preslia 92: 167-190. Consequences of Pilosella aurantiaca and P. rothiana (stabilized hybridogenous species P.
more » ... ioides > P. officinarum) spreading into three semi-ruderal localities in the city of Prague were studied. Numbers of chromosomes / DNA ploidy level and mode of reproduction are given for all the species and hybrids studied. Both P. aurantiaca and P. rothiana are apomictic and tetraploid with 2n = 4x = 36. Pilosella rothiana hybridizes with pentaploid P. piloselloides (P. ×heterodoxa, 2n = 6x = 53/54) and tetraploid P. officinarum (P. ×bifurca, 2n = 6x = 54). Pilosella aurantiaca hybridizes with tetraploid P. caespitosa (P. ×fuscoatra, 2n = 4x = 36), P. piloselloides (P. ×derubella, 2n = 5x = 45), P. officinarum (P. ×rubra, 2n = 6x) P. rothiana (2n = 6x = 54), P. ×bifurca (with 2n = 5x = 45) and P. visianii (tetraploid, 2n = 4x = 36). Hybrids of P. aurantiaca with tetraploid P. ×leptophyton were of two types, the tetraploid hybrid originating from parental reduced gametes and the hexaploid hybrid originating from a reduced and an unreduced parental gamete, respectively. Introgression from apomictic P. bauhini towards sexual P. officinarum was found in a hybrid swarm in one of the populations studied. Evolutionary potential of recent hybrids was evaluated with respect to their mode of reproduction; most of the recent hybrids were not apomictic. It seems impossible to predict the mode of reproduction from that of the parental species.
doi:10.23855/preslia.2020.167 fatcat:rag5wpxvwfb75lhxxgeuzrrk5q