Diversification of almonds, peaches, plums and cherries - Molecular systematics and biogeographic history of Prunus (Rosaceae)
Diversification of almonds, peaches, plums and cherries - Molecular systematics and biogeographic history of Prunus (Rosaceae)
复制标题
DOI：
10.1016/j.ympev.2014.02.024
复制
发表时间：
2014-07-01
影响因子：
4.1
通讯作者：
Potter, Dan
中科院分区：
文献类型：
--
作者：
Chin, Siew-Wai;Shaw, Joey;Potter, Dan
大多数以前的分子系统发育研究主要是与作物物种及其近亲进行。由于该属植物的多样性中心在欧亚大陆，因此不可避免地推断其地理起源也在欧亚大陆。在以前的系统发育重建中，鲜为人知的热带李属物种没有得到很好的代表，因此，它们对李属的系统发育结构和地理起源的推断的影响是不确定的。在这项研究中，我们研究了李属植物，包括从东南亚和美洲的热带地区的物种的扩大采样，从四个质体标记和核核糖体ITS区的序列。一个惩罚似然法被用来估计李属的绝对年龄和属下分支事件的时间。利用贝叶斯-DIVA方法推断了李属植物的地理起源和分支发生的祖先地点。我们的研究结果表明，现代属出现类似于61万年在东亚和多样化的所有主要谱系可能已引发的全球变暖时期的始新世早期。此外，我们的分子测年估计表明，包括温带落叶作物物种的冠支比包括热带万年青物种的冠支更古老，而质体和核间的不一致性表明，后者的谱系起源于一个古老的杂交事件。温带作物物种的最近共同祖先（MRCA）是北方半球连续的温带森林的组成部分，而热带物种的MRCA代表了温带成分的最后遗迹，随后从低纬度的避难所地区辐射到整个旧大陆和新大陆热带地区。导致该属目前全球分布的复杂地理历史是由几个地质事件，气候振荡和在不同地质时期通过白令和北大西洋陆桥跨越大陆的独立传播所驱动的。(C)2014年爱思唯尔公司All rights reserved.
Most previous molecular phylogenetic studies of Prunus have been conducted primarily with crop species and their close relatives. As the center of crop diversity of the genus is in Eurasia, the geographic origin of Prunus has inevitably been inferred to be Eurasia as well. The lesser-known tropical Prunus species have not been well represented in previous phylogenetic reconstructions; therefore, their effects on inferences about the phylogenetic structure and geographic origin of Prunus are uncertain. In this study, we examined the phylogeny of Prunus, including an expanded sampling of species from tropical regions in Southeast Asia and the Americas, using sequences from four plastid markers and the nuclear ribosomal ITS region. A penalized likelihood method was used to estimate the absolute age of Prunus and the timing of infrageneric cladogenic events. The geographic origin of Prunus and ancestral sites of cladogenesis were inferred using the Bayes-DIVA approach. Our results indicate that the modern genus appeared similar to 61 Myr in eastern Asia and that diversification of all major lineages may have been triggered by the global warming period of the early Eocene. In addition, our molecular dating estimates suggest that the crown clade that includes the temperate deciduous crop species is older than the one that includes the tropical evergreen species, while incongruence between plastid and nuclear phylogenies suggests that the latter lineage originated via an ancient hybridization event. The most recent common ancestor (MRCA) of the temperate crop species was a component of the continuous boreotropical forests of the Northern Hemisphere, while the MRCA of the tropical species represented the last remains of the boreotropical elements and subsequently radiated throughout the Old and New World tropics from refugial areas at lower latitudes. Complex biogeographic histories leading to the present global distribution of the genus were driven by several geologic events, climatic oscillations, and independent dispersals across continents via the Bering and the North Atlantic Land Bridges during different geologic time periods. (C) 2014 Elsevier Inc. All rights reserved.