Ultra-Tiny Scale Topographical Cues Direct Root Growth and Development.

Plant growth involves intricate processes, including cell division, expansion, and tissue organization, necessitating innovative technologies that emulate native cell-microenvironment interactions. Herein, we introduce ultra-tiny topographical cues (e.g., patterned micro/nanoscale substrates) that mimic micronanofiber structures found in the plant cell wall. We cultured on unique cell wall-inspired ultra-tiny cues within specialized chambers that positively influenced various physiological aspects compared to a flat surface. Specifically, we observed bidirectional behavior, favoring maximum primary root growth and thickness on sparse features (e.g., 5 μm) and induced predominant anisotropic root alignment on dense features (e.g., 400-800 nm), with alignment decreasing monotonically as the feature size increased. Additionally, RNA sequencing revealed distinct molecular mechanisms underlying root growth dynamics in response to these ultra-tiny cues, demonstrating modulation of specific genes involved in root development. Collectively, our findings highlight the potential of ultra-tiny cues to modulate gene expression and plant growth dynamics, offering innovative approaches to enhance agricultural productivity sustainably through feature-size-dependent interactions.