Strong associations exist between microbial communities and soil functions in natural ecosystems at large spatial scales; however, it is unclear whether these linkages are maintained in intensively managed croplands and whether these associations influence plant productivity. We collected bulk and rhizosphere soils from wheat fields –one of the most functionally and economically important crops worldwide –across the North China Plain (~300,000 km2), and examined the relationship between species-level multitrophic taxa, functional genes and wheat productivity. Our work identified significant and positive correlations of wheat productivity to the relative abundance of multitrophic clusters (co-occurring groups of soil biota including bacteria, fungi, arbuscular mycorrhizal fungi, and nematodes), and absolute abundance of functional genes associated with carbon, nitrogen, phosphorus, and sulfur cycles. We observed significant, biologically meaningful correlations between plant productivity and the abundance of specific root-associated microbial taxa and functional genes. These important linkages were robust when considered in combination with spatial, climate, and edaphic variables. Our findings highlight the importance of soil multitrophic communities in regulating soil functional potential and plant productivity, and provide a list of key-stone functional genes, which could be targeted to promote food security and production.
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