Life-history traits differ substantially among arbuscular mycorrhizal (AM) fungal families, potentially affecting hyphal nutrient acquisition e ciency, 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 Sudan grass (Sorghum sudanense) with AM fungal communities representing contrasting lifehistory traits and trait diversity: either 1) ve species in the AM family Gigasporaceae, representing competitor traits, 2) ve species in the family Glomeraceae, representing ruderal traits, or 3) a mixedfamily community combining all ten AM species. After 12 weeks, we measured above and below ground plant biomass and the uptake and concentration of 12 nutrients in aboveground biomass. Overall, AM fungal colonization increased host nutrition, biomass, and foliar 15 nitrogen enrichment compared to the uncolonized control. We observed the largest effects between the mixed-family community and the single-family communities for plant tissue quality, especially plant phosphorus (P), and in colonization rates. The mixed community increased plant P 1.2 and 1.3 times more than Glomeraceae and Gigasporaceae communities. However, this higher P did not translate to the greatest gains in plant biomass. Between the single-family communities, the Glomeraceae community generally outperformed the Gigasporaceae community in host nutrition and plant growth, increasing plant P concentrations 1.1 times more than the Gigasporaceae community. These ndings demonstrate that AM fungal community trait composition established at the family level affects plant nutrition and that AM family diversity increases colonization and plant tissue quality.

Fungi are crucial for soil organic carbon (SOC) formation, especially for the more persistent mineral-associated organic C (MAOC) pool. Yet, evidence for this often overlooks arbuscular mycorrhizal fungi (AMF) communities and how their composition and traits impact SOC accumulation.We grew sudangrass with AMF communities representing different traits conserved at the family level: competitors, from the Gigasporaceae family; ruderals, from the Glomeraceae family; or both families combined. We labeled sudangrass with 13 C-CO 2 to assess AMF contributions to SOC, impacts on SOC priming, and fungal biomass persistence in MAOC.Single-family AMF communities decreased total SOC by 13.8%, likely due to fungal priming. Despite net SOC losses, all AMF communities contributed fungal C to soil but only the Glomeraceae community initially contributed to MAOC. After a month of decomposition, both the Glomeraceae and mixed-family communities contributed to MAOC formation. Plant phosphorus uptake, but not hyphal chemistry, was positively related to AMF soil C and MAOC accumulation.Arbuscular mycorrhizal fungi contribution to MAOC is dependent on the specific traits of the AMF community and related to phosphorus uptake. These findings provide insight into how variations in AMF community composition and traits, and thus processes like environmental filtering of AMF, may impact SOC accumulation.

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 Sudan grass (Sorghum sudanense) with AM fungal communities representing contrasting life-history traits and trait diversity: either 1) five species in the AM family Gigasporaceae, representing competitor traits, 2) five species in the family Glomeraceae, representing ruderal traits, or 3) a mixed-family community combining all ten AM species. After 12 weeks, we measured above and below ground plant biomass and the uptake and concentration of 12 nutrients in aboveground biomass. Overall, AM fungal colonization increased host nutrition, biomass, and foliar 15nitrogen enrichment compared to the uncolonized control. We observed the largest effects between the mixed-family community and the single-family communities for plant tissue quality, especially plant phosphorus (P), and in colonization rates. The mixed community increased plant P 1.2 and 1.3 times more than Glomeraceae and Gigasporaceae communities. However, this higher P did not translate to the greatest gains in plant biomass. Between the single-family communities, the Glomeraceae community generally outperformed the Gigasporaceae community in host nutrition and plant growth, increasing plant P concentrations 1.1 times more than the Gigasporaceae community. These findings demonstrate that AM fungal community trait composition established at the family level affects plant nutrition and that AM family diversity increases colonization and plant tissue quality.