Can obligate apomixis and more stable reproductive assurance explain the distributional successes of asexual triploids in Hieracium alpinum (Asteraceae)?

0510445 - BÚ 2020 RIV DE eng J - Journal Article
Mráz, P. - Zdvořák, P. - Hartmann, M. - Štefánek, M. - Chrtek, Jindřich
Can obligate apomixis and more stable reproductive assurance explain the distributional successes of asexual triploids in Hieracium alpinum (Asteraceae)?
Plant Biology. Roč. 21, č. 2 (2019), s. 227-236. ISSN 1435-8603. E-ISSN 1438-8677
Institutional support: RVO:67985939
Keywords : apomixis * breeding system * FCSS * flow cytometry * fruit set * geographic parthenogenesis * polyploidy
OECD category: Plant sciences, botany
Impact factor: 2.167, year: 2019
Method of publishing: Limited access

Flow cytometric screening of embryos and endosperms of more than 4,100 seeds of Hieracium alpinum (Asteraceae) showed that diploids produced solely diploid progeny sexually, while triploids produced triploid progeny by obligate apomixis. Potential fruit set was much the same in diploids and triploids from the field and the greenhouse experiment. While in the pollination-limited environment in the greenhouse apomictic triploids had considerably higher realized fruit set than sexual diploids, there was no significant difference between cytotypes under natural conditions. In addition, sexuals varied to a significantly larger extent in realized fruit set than asexuals under both natural and greenhouse conditions. Our results indicate that triploid plants reproduce by obligate apomixis, assuring more stable and predictable fruit reproduction when compared to sexual diploids. This advantage could provide apomictic triploids with a superior colonisation ability, mirrored in a strong geographic parthenogenesis pattern observed in this species.
Permanent Link: http://hdl.handle.net/11104/0302695