Abstract：
Life-history traits differ substantially among arbuscular mycorrhizal (AM) fungal families, potentially affecting hyphal nutrient acquisition efficiency, host nutrition, and thereby plant health and ecosystem function. Despite these implications, AM fungal community life-history strategies and community trait diversity effects on host nutrient acquisition are poorly understood. To address this knowledge gap, we grew sudangrass with AM fungal communities representing contrasting life-history traits and diversity: either (1) five species in the AM family Gigasporaceae, representing competitor traits, (2) five Glomerales species, representing ruderal traits, or (3) a mixed-trait community combining all ten AM fungal species. After 12 weeks, we measured above and belowground plant biomass and aboveground nutrient uptake and concentration. Overall, AM fungal colonization increased host nutrition, biomass, and foliar δ5nitrogen enrichment compared to the uncolonized control. Between the single-trait communities, the Glomeraceae community generally outperformed the Gigasporaceae community in host nutrition and plant growth, increasing plant phosphorus (P) uptake 1.5 times more than the Gigasporaceae community. We saw weak evidence for a synergistic effect of the mixed community, which was only higher for plant P concentration (1.26 times higher) and root colonization (1.26 times higher) compared to the single-trait communities. However, this higher P concentration did not translate to more P uptake or the highest plant biomass for the mixed community. These findings demonstrate that the AM symbiosis is affected by community differences at high taxonomic levels and provide insight into how different AM fungal communities and their associated traits affect host nutrition for fast-growing plant species.
摘要：
丛枝菌根（AM）真菌家族之间的生活史特征差异很大，可能影响菌丝营养的获取效率，宿主营养，从而影响植物健康和生态系统功能。尽管有这些影响,AM真菌群落生活史策略和群落性状多样性对宿主养分获取的影响知之甚少。为了解决这个知识差距，我们用AM真菌群落生长了sudangrass，这些真菌群落代表了不同的生活史特征和多样性：（1）AM家族的Gigasporaceae中的五个物种，代表竞争对手的特质，(2)5种Glomerales，代表ruderal特征，或（3）结合了所有10种AM真菌的混合性状群落。12周后,我们测量了地上和地下植物的生物量以及地上养分的吸收和浓度。总的来说,AM真菌定植增加宿主营养，生物量，与未定殖对照相比，叶面δ5氮富集。在单特征社区之间，在寄主营养和植物生长方面，Glomerae群落通常优于Gigasporaceae群落，增加植物对磷（P）的吸收是Gigasporaceae群落的1.5倍。我们看到了混合社区协同作用的微弱证据，与单性状群落相比，植物P浓度（高1.26倍）和根定植（高1.26倍）仅较高。然而,这种较高的P浓度并没有转化为更多的P吸收或混合群落的最高植物生物量。这些发现表明，AM共生受高分类学水平的群落差异的影响，并提供了不同的AM真菌群落及其相关性状如何影响快速生长植物物种的宿主营养的见解。
