Genetic and clonal diversity for Myrica cerifera along a spatiotemporal island chronosequence
Genetic and clonal diversity for Myrica cerifera along a spatiotemporal island chronosequence
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DOI：
10.1038/sj.hdy.6800172
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发表时间：
2003-01-01
期刊：
影响因子：
3.8
通讯作者：
Hamrick, JL
中科院分区：
文献类型：
--
作者：
Erickson, DL;Hamrick, JL
以杨梅为研究对象，研究了其遗传多样性和克隆结构的时空岛型时序变化。在我们的研究地点，美国弗吉尼亚州的猪岛，岛屿运动产生了一系列沙丘脊和干预洼地，沿着岛屿的东西轴线，产生了年龄结构的地貌。这种基质介导的年龄结构，称为时间序列，叠加在M。在新生沙丘脊形成时在其后面定居的蜡树。这一时间序列允许比较不同年龄群体间的遗传多样性和克隆结构水平。蜡树属。我们观察到等位基因多样性沿着的时间序列变化不大，没有杂种优势的证据，虽然有适度的变化，基因型多样性。在10个地块内建立的个人的空间分布沿沿着三个横断面相交的岛屿时序确定了一个非随机的空间分布的个人在所有的队列，增加聚集的地上茎成多茎集群在较老的网站。个体的这种聚集并不对应于克隆生长随队列年龄的显著增加，也没有显着的空间遗传自相关内的任何图。
Changes in genetic diversity and clonal structure were investigated along a spatiotemporal island chronosequence for the shrub Myrica cerifera. On our study site, Hog Island, Virginia, USA, island movement creates a sequence of dune ridges and intervening swales along an east-west axis of the island that produces an age-structured geomorphology. This substrate-mediated age structure, called the chronosequence, superimposes itself upon cohorts of M. cerifera that colonize behind nascent dune ridges as they are formed. This chronosequence allowed comparisons of levels of genetic diversity and clonal structure among different aged cohorts of M. cerifera. We observed little change in allelic diversity along the chronosequence and no evidence for heterosis, although there was moderate change in genotypic diversity. The spatial distribution of individuals within 10 plots established along three transects intersecting the island chronosequence identified a nonrandom spatial distribution of individuals in all cohorts, with increasing aggregation of above-ground stems into multistemmed clusters in the older sites. This aggregation of individuals did not correspond to a significant increase in clonal growth with cohort age, nor was there significant spatial genetic autocorrelation within any of the plots.