Nutrients as signals that spatially organize plant-microbe interactions.

Plant-microbe interactions are spatially organized processes. Increasing evidence suggests that nutrients play a critical role in this organization by not only acting as resources but also as spatial signals. In plants, nutrient perception and signaling are spatially patterned across tissues, while in microbes, local nutrient conditions guide colonization, metabolism, and function. These responses create heterogeneous interaction niches at the plant-microbe interface, but how they are coordinated across individual cells remains unclear. Recent advances in single-cell, spatial omics and nutrient mapping approaches now enable these processes to be resolved at cellular resolution. Here, we bring together current understanding of nutrient-guided plant and microbial responses and highlight emerging technologies that allow their integration. We then introduce a cell-state framework to interpret plant-microbe interactions as emergent properties of spatially coupled cellular responses linked through local chemical environments. This perspective provides a foundation for a more mechanistic and predictive understanding of plant-microbe interactions.