Nanoregulators in Plants: Mechanisms of Uptake, Transport, and Stress Resistance

Nanomaterials (NMs), owing to their inherent redox-modulating and light-conversion properties, could mitigate diverse abiotic/biotic stresses in plants, thereby offering a novel nanotechnology-driven strategy for sustainable agriculture. Herein, the uptake and translocation pathways of NMs in plants were summarized, along with the influence of NM properties (size/surface charge/surface coating) on translocation efficiency. Notably, meta-analysis of published data revealed that NM dose (4.2 × 1002∼ 2 × 10–03 mg plant–1, rs = −0.437), size (6.5 ∼ 1000 nm, rs = −0.233), and surface charge (−47.6∼+30 mV, rs = −0.253) exhibit significant negative correlations with transport efficiency, serving as key determinants for phloem-based leaf-to-sink translocation. Furthermore, thanks to their optical properties, NMs enhance photosynthetic efficiency in plants, and their enzyme-mimicking functions serve to mitigate stress-induced oxidative stress. Moreover, owing to their capacity for translocation through vascular systems, even internalization to cellular levels, NMs induce transcriptional reprogramming that coordinately upregulate photosystem components and stress-responsive signaling pathways.