长期以来,全基因组复制因其在驱动植物表型新颖性方面的作用而受到赞赏,经常改变生物与非生物环境的连接方式。只是最近,然而,我们已经开始研究多倍体如何影响植物与其他物种的相互作用,尽管生物生态位被预测为多倍体建立的主要决定因素之一。然而,我们缺乏关于多倍体如何影响定殖植物的微生物分类群的多样性和组成的信息,以及这是否依赖于基因型并且在自然环境中可重复。这些信息是了解微生物组是否有助于多倍体建立的第一步。我们,因此,使用四对二倍体和合成四倍体,测试了多倍体对水生植物Spirodelapolyrhiza细菌微生物组的多样性和组成的直接影响。在受控条件下,在广泛的环境梯度上,从10个田间地点收集的池塘水接种了无菌植物。自倍体的细菌分类学和系统发育多样性比其二倍体祖细胞高4%-11%。多倍体,以及它与接种物来源和遗传谱系的相互作用,共同解释了微生物组组成总变异的7%。此外,多倍体扩大了核心微生物组,与同源四倍体具有15个独特的细菌分类群,除了与二倍体共有的55个。我们的结果表明,全基因组复制直接导致植物微生物组的新颖性,重要的是,这种影响取决于多倍体的遗传祖先,并且可以在许多环境背景下推广。
Whole-genome duplication has long been appreciated for its role in driving phenotypic novelty in plants, often altering the way organisms interface with the abiotic environment. Only recently, however, have we begun to investigate how polyploidy influences interactions of plants with other species, despite the biotic niche being predicted as one of the main determinants of polyploid establishment. Nevertheless, we lack information about how polyploidy affects the diversity and composition of the microbial taxa that colonize plants, and whether this is genotype-dependent and repeatable across natural environments. This information is a first step towards understanding whether the microbiome contributes to polyploid establishment. We, thus, tested the immediate effect of polyploidy on the diversity and composition of the bacterial microbiome of the aquatic plant Spirodela polyrhiza using four pairs of diploids and synthetic autotetraploids. Under controlled conditions, axenic plants were inoculated with pond waters collected from 10 field sites across a broad environmental gradient. Autotetraploids hosted 4%-11% greater bacterial taxonomic and phylogenetic diversity than their diploid progenitors. Polyploidy, along with its interactions with the inoculum source and genetic lineage, collectively explained 7% of the total variation in microbiome composition. Furthermore, polyploidy broadened the core microbiome, with autotetraploids having 15 unique bacterial taxa in addition to the 55 they shared with diploids. Our results show that whole-genome duplication directly leads to novelty in the plant microbiome and importantly that the effect is dependent on the genetic ancestry of the polyploid and generalizable over many environmental contexts.