Plant community and soil properties drive arbuscular mycorrhizal fungal diversity: A case study in tropical forests

The mutual interdependence of plants and arbuscular mycorrhizal fungi (AMF) is important in.carbon and mineral nutrient exchange. However, an understanding of how AMF community.assemblies vary in different forests and the underlying factors regulating AMF diversity in.native tropical forests is largely unknown. We explored the AMF community assembly and the.underlying factors regulating AMF diversity in a young (YF) and an old-growth forest (OF) in.a tropical area. The results showed that a total of 53 AMF phylogroups (virtual taxa, VTs).were detected, 38±1 in the OF and 34±1 in the YF through high-throughput sequencing of.18S rDNA, and AMF community composition was significantly different between the two.forests. A structural equation model showed that the forest traits indirectly influenced AMF.diversity via the plant community, soil properties and microbes, which explained 44.2% of the.total observed variation in AMF diversity. Plant diversity and biomass were the strongest.predictors of AMF diversity, indicating that AMF diversity was dominantly regulated by biotic.factors at our study sites. Our study indicated that forest community traits have a predictable.effect on the AMF community; plant community traits and soil properties are particularly.important for determining AMF diversity in tropical forests.

植物与丛枝菌根真菌（AMF）之间的相互依存关系在碳和矿质养分交换中至关重要。然而，对于不同森林中AMF群落组成如何变化，以及调节原生热带森林中AMF多样性的潜在因素，我们知之甚少。我们探究了热带地区一片幼龄林（YF）和一片老龄林（OF）中AMF群落的组成，以及调节AMF多样性的潜在因素。结果显示，通过对18S rDNA进行高通量测序，共检测到53个AMF系统发育类群（虚拟分类单元，VTs），老龄林中为38±1个，幼龄林中为34±1个，且这两片森林中的AMF群落组成存在显著差异。结构方程模型表明，森林特征通过植物群落、土壤性质和微生物间接影响AMF多样性，这解释了所观测到的AMF多样性总变异的44.2%。植物多样性和生物量是AMF多样性最强的预测因子，这表明在我们的研究地点，AMF多样性主要受生物因素调控。我们的研究表明，森林群落特征对AMF群落具有可预测的影响；植物群落特征和土壤性质对于决定热带森林中的AMF多样性尤为重要。