Wheat pot experiment bacteria microbiome Raw sequence reads

Rhizosphere microbial communities adapt in their structural and functional composition to water scarcity and have the potential to substantially mitigate drought stress of plants. Understanding the interplay between drought stress, soil type, farming system and plant genotype are central to benefit from this potential. We tested the hypothesis that drought modifies rhizosphere communities to stimulate plant growth under drought stress.Two wheat cultivars were planted in Haplic Chernozem and Albic Luvisol under conventional and organic farming, with and without drought stress. Rhizosphere microbiome and plant growth were investigated in the first year, and plant growth in the second year.Prokaryote community composition was strongly driven by soil type and farming system. An increase in Gram-positive phyla was most pronounced in Albic Luvisol and in organic farming under drought. Rhizosphere enzyme activities and functional gene abundances were strongly affected by soil type, farming system and drought, and further modified by wheat cultivar. Drought limited wheat biomass in the first year, but in the second year, drought conditioned organic farming soils increased plant growth under drought. We show that soil type, farming system and drought are strong drivers of rhizobacterial communities, which interact and modify the consequences of drought to soil-plant feedback.