Frequent occurrence of triploid hybrids Festuca pratensis × F. apennina in the Swiss Alps

0495303 - ÚEB 2019 RIV CH eng J - Journal Article
Kopecký, David - Felder, T. K. - Schubiger, F. X. - Mahelka, Václav - Bartoš, Jan - Doležel, Jaroslav - Boller, T.
Frequent occurrence of triploid hybrids Festuca pratensis × F. apennina in the Swiss Alps.
Alpine Botany. Roč. 128, č. 2 (2018), s. 121-132. ISSN 1664-2201. E-ISSN 1664-221X
R&D Projects: GA MŠMT(CZ) LO1204
Institutional support: RVO:61389030 ; RVO:67985939
Keywords : flow-cytometry * miscanthus-sacchariflorus * species composition * genetic diversity * chloroplast dna * southern japan * plants * polyploidy * angiosperms * population * Asexual reproduction * Triploid * Grass * Festuca * Hybrid * Clonality * Fescue
OECD category: Plant sciences, botany
Impact factor: 2.719, year: 2018

The occurrence of triploid hybrids in nature is scarce due to the so-called triploid block representing formation of nonviable progeny after mating diploid with tetraploid. Here we describe frequent presence of triploids originating from hybridization of diploid Festuca pratensis with tetraploid F. apennina in the Swiss Alps. F. pratensis is a forage grass grown in lowlands and up to 1800m a.s.l., while F. apennina is a mountain grass found in elevations from 1100 to 2000m a.s.l. In the overlapping zone these species often grow sympatrically and triploid hybrids have been observed. We show that elevation is the main factor in the distribution of plants with various ploidy levels. Diploids occupy lower elevations, while triploids predominate in the mid-elevation zones and tetraploids are the most frequent in higher elevations. Other factors, such as topography and soil composition probably have only marginal effects on the distribution of the plants with different ploidy levels. Triploids seem to be frequently formed in the Swiss Alps and crosses in both directions are involved in the formation of triploid hybrids. As shown by chloroplast DNA analysis, F. apennina more frequently serves as female. Our analysis suggests that in the mid-elevation zones, triploids have a higher level of competitiveness than both parents. Triploids can overgrow microhabitats to a much higher extent than tetraploids. Such frequent occurrence and local dominance of triploids can at least be partially explained by asexual reproduction. Using DNA markers, we show that triploids can disperse ramets of a single clone over a distance of at least 14.4m.
Permanent Link: http://hdl.handle.net/11104/0288301