Auxin-Functionalized Nanocarriers Hijack Endogenous Transport for Systemic Crop Protection in Plants

Area of Science:

• Plant Science
• Nanotechnology
• Agricultural Science

Background:

• Targeted delivery of functional agents to specific plant organs is a significant challenge.
• Synthetic materials typically do not access endogenous long-distance transport pathways in plants.

Purpose of the Study:

• To develop a nanocarrier strategy for programmable systemic transport in plants by interfacing engineered materials with plant signaling networks.
• To enable efficient root-targeted delivery of agrochemicals via foliar application.

Main Methods:

• Engineered nanocarriers (∼55 nm) functionalized with auxin motifs on their surface to favor extracellular localization and limit endocytosis.
• Hijacking polar auxin transport pathways by interfacing nanocarriers with plant signaling networks, specifically enhancing PIN-mediated fluxes and PIN1 expression.
• Evaluating the systemic transport and accumulation of nanocarriers in plant tissues, particularly in roots.

Main Results:

• Achieved directional leaf-to-root transport over centimeter scales, with a 72.32-fold increase in root accumulation due to enhanced PIN-mediated fluxes and PIN1 upregulation.
• Demonstrated efficient root-targeted delivery of abamectin via foliar application, resulting in up to 79.71% control of root-knot nematodes.
• Reduced pesticide input by half, providing a 3.20-fold higher ecological safety margin and a 16.47% increase in crop production.

Conclusions:

• The auxin-functionalized nanocarrier strategy enables programmable systemic transport by interfacing with plant signaling pathways.
• This approach offers an effective method for root-targeted agrochemical delivery, enhancing crop protection and sustainability.
• Established a generalizable design principle for synthetic materials to navigate biological transport systems, opening new avenues for crop protection and bio-integrated material delivery.