Systematics and Evolution of Vascular Plants (UAB)-Associated Unit to CSIC, Unitat de Botànica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Sassari, Italy.
PLoS One. 2020 Feb 7;15(2):e0228776. doi: 10.1371/journal.pone.0228776. eCollection 2020.
The Mediterranean Basin is a biodiversity hotspot, where islands play a key role because of their high biological diversity, degree of endemicity and human pressure. One of these islands, Sardinia, is a good evolutionary laboratory, especially for the study of complex genera, such as Centaurea. In particular, endemic species of Centaurea sect. Centaurea from Sardinia provides an interesting case study of plant evolution on continental islands. We attempted to clarify the processes leading to the diversification of Centaurea species on Sardinia using bi-parentally inherited nuclear markers and maternally inherited plastid markers. Our plastid results revealed the presence of five lineages of sect. Centaurea on the island. Three of them were defined as three species: C. ferulacea, C. filiformis and C. horrida. The other two lineages highlighted the complex evolutionary history of the two polyploids C. corensis and C. magistrorum. Multiple colonization events from the mainland involving the C. deusta and C. paniculata lineages among others, have led to the diversity of sect. Centaurea on Sardinia. One colonization event likely followed a southern path via the land connection between the mainland, the Calabrian Plate and Sardinia. A second pathway likely followed a northern connection, probably through the Tuscan Archipelago. Implications of these findings on conservation efforts for Centaurea endemics on Sardinia are also discussed.
地中海盆地是一个生物多样性热点地区，岛屿在其中起着关键作用，因为它们具有高度的生物多样性、特有性程度和人类压力。这些岛屿之一的撒丁岛是一个很好的进化实验室，特别是对于研究复杂属，如矢车菊属。特别是，撒丁岛特有的矢车菊属节。Centaurae 为研究大陆岛屿上的植物进化提供了一个有趣的案例。我们试图用双亲遗传的核标记和母系遗传的质体标记来阐明导致撒丁岛矢车菊物种多样化的过程。我们的质体结果显示，该岛上存在五个节。Centaurae 谱系。其中三个被定义为三个物种：C. ferulacea、C. filiformis 和 C. horrida。另外两个谱系突出了两个多倍体 C. corensis 和 C. magistrorum 的复杂进化历史。来自大陆的多次殖民事件涉及 C. deusta 和 C. paniculata 等谱系，导致了撒丁岛节。Centaurae 的多样性。一次殖民事件可能沿着南部路径通过大陆、卡拉布里亚板块和撒丁岛之间的陆地连接进行。第二个途径可能沿着北部连接进行，可能通过托斯卡纳群岛。还讨论了这些发现对撒丁岛矢车菊特有种保护工作的影响。
