Data from: Characterization of microsatellite loci and reliable genotyping in a polyploid plant, Mercurialis perennis (Euphorbiaceae)

For many applications in population genetics, codominant simple sequence repeats (SSRs)
may have substantial advantages over dominant anonymous markers such as AFLPs. In high
polyploids, however, allele dosage of SSRs cannot easily be determined and alleles are not
easily attributable to potentially diploidized loci. Here, we argue that SSRs may nonetheless be
better than AFLPs for polyploid taxa if they are analyzed as effectively dominant markers,
because they are more reliable and more precise. We describe the transfer of SSRs developed
for diploid Mercurialis huetii to the clonal dioecious M. perennis. Primers were tested on a set of
54 male and female plants from natural decaploid populations. Eight of 65 tested loci produced
polymorphic fragments. Binary profiles from four different scoring routines were used to define multilocus lineages (MLLs). Allowing for fragment differences within one MLL, all analyses
revealed the same 14 MLLs, without conflicting with merigenet, sex or plot assignment. For semiautomatic scoring, a combination of as few as two of the four most polymorphic loci resulted in unambiguous discrimination of clones. Our study demonstrates that microsatellite fingerprinting of polyploid plants is a cost-efficient and reliable alternative to AFLPs, not least
because fewer loci are required than for diploids.

在种群遗传学的诸多应用场景中，共显性简单序列重复（Simple Sequence Repeats, SSRs）相较于扩增片段长度多态性（AFLPs）这类显性匿名标记，具备显著优势。然而在高倍体物种中，难以确定SSRs的等位基因剂量，也难以将等位基因归因于潜在的二倍化位点。本研究认为，若将SSRs作为有效显性标记进行分析，其仍可优于AFLPs应用于多倍体类群，原因在于SSRs具备更高的可靠性与精准度。我们将为二倍体休氏山靛（Mercurialis huetii）开发的SSRs标记转移应用于克隆繁殖且雌雄异株的多年生山靛（M. perennis）。以自然十倍体种群中的54株雌雄植株为材料，我们对引物开展了测试。65个检测位点中，有8个可扩增出多态性片段。采用四种不同评分方法得到的二元谱图，用于界定多位点谱系（Multilocus Lineages, MLLs）。若允许单个MLL内存在片段差异，所有分析均得到了14个一致的MLLs，且与基株、性别及样地划分均无冲突。对于半自动评分流程，仅需选取四个多态性最高的位点中的两个进行组合，即可实现对克隆株的明确区分。本研究证实，针对多倍体植物的微卫星指纹图谱技术，相较于AFLPs是一种经济高效且可靠的替代方案，尤其其所需的位点数较二倍体物种更少。