Development of highly polymorphic genomic microsatellite markers and their application to gene flow in a natural population of <i>Abies firma</i>

The momi fir (<i>Abies firma</i>) has been targeted as a species for genetic resource conservation because of the recent decline in its natural populations. Additional molecular marker resources are needed to examine gene flow to understand the genetic dynamics of each population. We developed 15 genomic microsatellite (SSR) markers for <i>A. firma</i> and applied them to separate biparentage assignments of dispersed seeds in a natural population by assaying embryos and megagametophytes. The 15 markers were polymorphic, with the expected heterozygosity averaging greater than 0.74. Separate biparentage analysis, using the seven selected effective markers, was successful to assign paternal and maternal trees separately and thus estimate the paternal and maternal immigrant gene flow from nearby populations. The newly developed genomic SSR markers in the present study, by constructing a marker set together with previously developed markers, will provide higher discriminatory power for parentage analysis and should be useful for estimating gene flow for ongoing conservation genetics studies of <i>A. firma</i>.日本冷杉（Abies firma）因自然种群近期出现衰退，已被列为遗传资源保护的目标物种。为探究种群基因流以阐明各群体的遗传动态，亟需开发更多的分子标记资源。本研究为日本冷杉开发了15个基因组微卫星（Simple Sequence Repeat, SSR）标记，并通过对胚与大配子体进行基因分型，将该套标记应用于天然种群中散布种子的双亲溯源分析。该15个标记均具有多态性，平均预期杂合度超过0.74。通过筛选出的7个高效标记开展独立的双亲溯源分析，可成功分别确定父本与母本植株，进而估算来自邻近种群的父本与母本迁入基因流。本研究新开发的基因组SSR标记，若与已有的标记整合为一套标记体系，将为亲本溯源分析提供更高的识别效力，且可用于日本冷杉后续保护遗传学研究中的基因流估算，具备重要应用价值。