Fig trees at the northern limit of their range: the distributions of cryptic pollinators indicate multiple glacial refugia
Fig trees at the northern limit of their range: the distributions of cryptic pollinators indicate multiple glacial refugia
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无花果树位于其分布范围的北端：神秘传粉媒介的分布表明存在多个冰川保护区
DOI：
10.1111/j.1365-294x.2012.05491.x
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发表时间：
2012-04-01
影响因子：
4.9
通讯作者：
Chen, Xiao-Yong
中科院分区：
文献类型：
--
作者：
Chen, Yan;Compton, Stephen G.;Chen, Xiao-Yong
过去几百万年的气候振荡对温带动植物的分布和基因组的影响有据可查，但对其对热带和亚热带物种的影响知之甚少。与欧洲和北美相比，中国冰川时期的冰盖并不覆盖大部分地区，冰川周期的影响也不那么戏剧性。无花果树是一个主要由寄主特有的无花果黄蜂授粉的热带类群。我们利用线粒体COI(918bp)和核ITS2(462bp)的部分基因序列研究了为亚洲热带榕树授粉的黄蜂的遗传结构和种群历史。位于中国东南部的普米拉。线粒体基因(7.211.6%)和核基因(1.62.9%)存在较大的遗传差异，表明存在3种传粉者，它们的遗传差异约为4.72和6.00 Myr。这早于第四纪冰期，但与台湾海峡的形成和武夷仙峡山脉的抬升相对应。这三种传粉者在中国具有基本的异地分布格局，并显示出不同的冰后人口史。维贝西亚(Wiebesia spp.)1和2分别占据了大陆寄主范围的北部和南部地区。它们的种群都经历了显著的冰川后空间扩张，但时间和速度不同。Wiebesia sp.3主要局限于北部岛屿，显示出较少的近期人口扩张的证据。它们的主要异地分布和不同的人口历史与寄主植物在三个不同避难所的冰后扩张相一致，并暗示了无花果树获得多个传粉者的一种机制。
Climatic oscillations during the last few million years had well-documented effects on the distributions and genomes of temperate plants and animals, but much less is known of their impacts on tropical and subtropical species. In contrast to Europe and North America, ice-sheets did not cover most of China during glacial periods, and the effects of glacial cycles were less dramatic. Fig trees are a predominantly tropical group pollinated by host-specific fig wasps. We employed partial mitochondrial COI (918 bp) and nuclear ITS2 (462 bp) gene sequences to investigate the genetic structure and demographic histories of the wasps that pollinate the subtropical Ficus pumila var. pumila in Southeastern China. Deep genetic divergence in both mitochondrial (7.211.6%) and nuclear genes (1.62.9%) indicates that three pollinator species are present and that they diverged about 4.72 and 6.00 Myr bp. This predates the Quaternary ice ages, but corresponds with the formation of the Taiwan Strait and uplifting of the WuyiXianxia Mountains. The three pollinators have largely allopatric distribution patterns in China and display different postglacial demographic histories. Wiebesia spp. 1 and 2 occupy, respectively, the northern and southern regions of the mainland host range. Their populations both underwent significant postglacial spatial expansions, but at different times and at different rates. Wiebesia sp. 3 is largely restricted to northern islands and shows less evidence of recent population expansion. Their mainly allopatric distributions and different demographic histories are consistent with host plant postglacial expansion from three distinct refugia and suggest one mechanism whereby fig trees gain multiple pollinators.