The root exudates of wild tomato as compared to a modern variety maintain elevated soluble soil phosphorous by interacting with its rhizosphere microbiota
Wild plants are periodically exposed to nutrient flushes, whereas modern cultivars are acclimated to regular nutrition from fertilizers. Phosphorus (P) fertilizers, however, convert into unavailable forms when applied to soil. Here, we assessed plant growth, rhizosphere microbiome, and root exudation of a wild and modern tomato in P sufficiency to determine how a wild crop relative deals with a flush of P fertilization. We initially found that the modern tomato relatively lacked P-mineralizing microbes and grew quickly, thus depleting soil P. Conversely, wild tomato continued growth and promoted a diverse array of beneficial soil bacteria, which resulted in higher pools of bioavailable soil P across development. This microbial strategy was driven by its root exudates, which subsequently found to be enriched in trehalose and glycerol compounds. In vitro testing showed that these compounds promoted microbial P solubilization. Finally, we grew modern tomato in P-fertilized soils following a previous planting of either wild or modern tomato. Modern tomato grown in wild tomato-conditioned soils increased biomass compared to those grown in modern tomato-conditioned soils. The increased biomass may be principally associated with residual soil P as the wild-induced microbial community changes diminished. The root exudate driven strategy of wild tomato helps maintain soluble soil P and may be utilized in agriculture to help prevent fertilizer loss. These data contain the ONT 16S rRNA sequences corresponding to this research project.