Gene flow between diploid and tetraploid junipers - two contrasting evolutionary pathways in two Juniperus populations

BMC Evolutionary Biology

Robert P. Adams¹  Perla Farhat²  Carlos Salazar-Mendias³  Joaquín Altarejos⁴  Nicolas Valentin⁵  Silvia Lopez-Udias⁶  Carlos Fabregat⁶  Sonja Siljak-Yakovlev⁷ 

[1] Biology Department, Baylor University, 76798, Waco, TX, USA;Biology Department, Baylor University, 76798, Waco, TX, USA;Present address: Key Laboratory of Bio-resources and Eco-environment, College of Life Sciences, Sichuan University, 610064, Chengdu, Sichuan, China;Departamento de Biología Animal, Biología Vegetal y Ecología. Universidad de Jaén, 23071, Jaén, Spain;Departamento de Química Inorgánica y Orgánica, Universidad de Jaén, 23071, Jaén, Spain;Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198, Gif-sur-Yvette, France;Jardí Botànic de la Universitat de València, 46008, València, Spain;Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique Evolution, 91405, Orsay, France;

关键词: Juniperus;    Gene flow;    Polyploidy;    Triploid bridge;    Hybridization;    Introgression;    Spain;    Conifer evolution;   

DOI  :  10.1186/s12862-020-01688-3

来源: Springer

【 摘 要 】

BackgroundGene flow and polyploidy have been found to be important in Juniperus evolution. However, little evidence has been published elucidating the association of both phenomena in juniper taxa in the wild. Two main areas were studied in Spain (Eastern Iberian Range and Sierra de Baza) with both diploid and tetraploid taxa present in sympatry. Gene flow and ploidy level were assessed for these taxa and the resulted offspring.ResultsTwenty-two allo-triploid hybrids between J. sabina var. sabina and J. thurifera were found in the Eastern Iberian Range population. However, in the Sierra de Baza population no triploids were found. Instead, 18 allo-tetraploid hybrids between two tetraploid taxa: J. sabina var. balkanensis and J. thurifera were discovered. High genetic diversity was exhibited among the tetraploid hybrids at Sierra de Baza, in contrast to the genetically identical triploid hybrids at the Eastern Iberian Range; this suggests meiotic difficulties within the triploid hybrids. In addition, unidirectional gene flow was observed in both studied areas.ConclusionPolyploidy and hybridization can be complementary partners in the evolution of Juniperus taxa in sympatric occurrences. Juniperus was shown to be an ideal coniferous model to study these two phenomena, independently or in concert.

【 授权许可】

CC BY