Аннотация:Plant microbiome (treated as a sum of bacteria and fungi) associated with underground plant part is discussed from the plant nutrition perspective. The role of rhizosphere microorganisms and mycorrhizal fungi in plant uptake of phosphorus, nitrogen, potassium, sulphur and iron is considered with the focus on microbe potential in the sustainable agriculture. The mechanisms of microbial plant-beneficial action are provided when possible, the ambiguity and complexity of microorganisms’ effects in plant performance is emphasized and the future research avenues are outlined in the chapter.