Root‐Applied Phyto‐Courier Loaded With Rutin Translocates to Aerial Tissues Inducing Molecular and Anatomical Changes in <i>Cannabis sativa</i> Under Salinity

ABSTRACT Nanotechnologies offer promising solutions for safeguarding crops in a sustainable and efficient manner, particularly under adverse conditions. This study investigates the effects of the phyto‐courier, a formulation comprising silicon‐stabilized hybrid nanoparticles (NPs) loaded with rutin, in the fiber‐type variety of Cannabis sativa Santhica 27 (with a tetrahydrocannabinol‐THC content&lt;0.2%) after confirming its translocation to aerial organs when applied to roots via soil drenching. In non‐stressed roots, the treatment enhances xylem and sclerenchyma development. Under salinity, the formulation preserves the palisade mesophyll structure in leaves. In both stressed and unstressed plants, the rutin‐loaded phyto‐courier stimulates bast fiber formation. Gene expression analysis conducted on plants under control conditions and salinity, alongside untargeted metabolomics focused on hemp under control conditions, reveals changes in both leaves and roots, highlighting the phyto‐courier's ability to exert effects on organs distant from the site of application. Stress‐related genes show a trend toward up‐regulation in the absence of salinity and in the presence of the rutin‐loaded phyto‐courier, denoting priming. Metabolomics confirmed priming via the control of ethylene levels and the jasmonic acid (JA)‐mediated stress response. This study demonstrates that the rutin‐loaded phyto‐courier enhances hemp resilience to salt stress and promotes bast fiber development, offering a promising approach for crop productivity improvements.