Big thistle eats the little thistle : does unidirectional introgressive hybridization endanger the conservation of Onopordum hinojense?

© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 206(2015), 1 vom: 10. Apr., Seite 448-458
1. Verfasser: Balao, Francisco (VerfasserIn)
Weitere Verfasser: Casimiro-Soriguer, Ramón, García-Castaño, Juan Luis, Terrab, Anass, Talavera, Salvador
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2015
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Onopordum amplified fragment length polymorphism (AFLP) extinction genome scan hybridization morphology outlier loci unidirectional introgression Genetic Markers
Beschreibung
Zusammenfassung:© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.
Hybridization is known to have a creative role in plant evolution. However, it can also have negative effects on parental species. Onopordum is a large genus whose species frequently hybridize. In the Southwest Iberian Peninsula, the rare O. hinojense co-occurs with the widely distributed O. nervosum, and hybrids between these two taxa have been described as O. × onubense. In this study we determine the extinction risk in a hybrid zone, both for hybrids and parentals, using analyses of morphological and cytogenetic traits as well as genetic markers and demographic models. To investigate the introgression process we used amplified fragment length polymorphism (AFLP) markers, Bayesian analyses and genome scan methods. Morphology, genome size and molecular markers confirmed homoploid hybridization and also indicated unidirectional backcrossing of F₁ hybrids with O. nervosum, which is likely to swamp O. hinojense, the parental with lower pollen size and a very low fruit set (8%). Genome scan methods revealed several loci significantly deviating from neutrality. Finally, our demographic modeling indicated that the higher fitness of O. nervosum threats the survival of O. hinojense by demographic swamping. Our study provides strong new evidence for a scenario of rapid extinction by unidirectional introgression and demographic swamping. The multifaceted approach used here sheds new light on the role of introgression in plant extinctions
Beschreibung:Date Completed 11.02.2016
Date Revised 09.11.2020
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.13156