P-315 - Decoding Plant-Microbiome Interactions Under Phosphate Starvation at Single-Cell and Spatial Resolutions

Plant-microbiome interactions are crucial for plant health, promoting growth and enhancing resilience under stress conditions such as nutrient deficiency. Although these interactions are highly spatially organized and heterogeneous, this complexity is often masked by traditional bulk tissue analyses. As a result, how individual root cells perceive environmental stress and microbial cues and coordinate responses across spatial contexts remains poorly understood. Here we use PHYTOMap, a multiplexed 3D spatial gene expression platform, to investigate plant-microbiome interactions under phosphate starvation. Using Arabidopsis and a synthetic microbial community, we visualize spatial patterns of plant gene expression alongside microbial colonization in intact root tissues. We further examine responses in phr1/phl1mutants, which are deficient in phosphate starvation signaling, to observe how altered phosphate responses impact microbiome colonization and plant gene expression patterns at single-cell and spatial resolution. As a future direction, we propose to complement this spatial framework with single-nucleus omics approaches to further uncover the regulatory mechanisms driving these interactions. Altogether, this research will significantly advance our understanding of how plants shape their microbiome under phosphate stress, providing a foundation for innovative strategies to enhance crop resilience and agricultural sustainability.