Engineering Porous Nano-Organic Silicon for Enhanced Pesticide Performance in Drone Spraying

Area of Science:

• Materials Science
• Nanotechnology
• Agricultural Chemistry

Background:

• Toosendanin (TSN) is a natural pesticide with potential for crop protection.
• Improving the stability, efficacy, and application methods of TSN is crucial for sustainable agriculture.

Purpose of the Study:

• To synthesize a novel porous nano-organic silicon (PNOS) polymer for encapsulating TSN.
• To evaluate the physicochemical properties, stability, and efficacy of TSN-loaded PNOS nanoparticles.
• To develop and assess a TSN nanosuspension for drone-based aerial application in crop protection.

Main Methods:

• Synthesis of PNOS using template-assisted polymerization and acid etching with nano-CuO.
• Characterization of PNOS particle size, surface area (BET), and pore adsorption via XPS and molecular docking.
• Encapsulation of TSN within PNOS, followed by stability and photostability assessments.
• Formulation of a TSN nanosuspension with optimized adjuvants.
• Evaluation of nanosuspension properties (suspension rate, stability, wetting).
• Assessment of aerial application suitability (droplet density, coverage).
• Toxicity assays (LC50) against aphids and field efficacy trials.

Main Results:

• PNOS particles (50-150 nm) showed a high BET surface area (426.0 m²/g).
• PNOS achieved 31.5% TSN loading capacity, supported by hydrogen-bond interactions.
• Nanoencapsulation increased TSN half-life from 2.7 to 8.6 days, enhancing photostability.
• The developed TSN nanosuspension exhibited favorable suspension, stability, and wetting properties.
• Aerial application demonstrated high droplet density and canopy coverage.
• TSN nanosuspension showed significantly lower LC50 values against aphids compared to emulsifiable concentrate.
• Field trials confirmed desirable control efficacy and long persistence against aphids via aerial spraying.

Conclusions:

• Novel PNOS polymer is effective for TSN nanoencapsulation, improving its stability and efficacy.
• The developed TSN nanosuspension is suitable for sustainable aerial crop protection using drones.
• PNOS-based TSN formulations offer a promising alternative for integrated pest management.