Medicago truncatula adjusts root proliferation, nodule formation, and partner choice in response to local N heterogeneity

AimsIncreases in anthropogenic nitrogen (N) deposition are expected to lead to an overall higher mean and lower variance of N in the soil, which may disproportionately affect leguminous plants that acquire N both symbiotically via rhizobia and abiotically from soil. Here, we investigate the effects of changing N-heterogeneity at a fine spatial scale on the legume-rhizobium symbiosis.MethodsWe used a split-root system to introduce local soil …