Pesticides and Methods For Treating Cercospora Leaf Spot Disease

Cercospora leaf spot (CLS), caused by Cercospora beticola, is the most widespread and destructive foliar disease in sugar beet crops, often leading to yield losses of up to 50%. Traditional control methods rely on fungicide sprays and resistant cultivars. However, fungicide-resistant fungal strains, environmental wash-off due to rain, and frequent reapplication needs compromise their effectiveness and increase costs. There is a critical need for a more sustainable, effective, and durable method to deliver fungicidal agents to plant leaves.

Invention Summary

This technology introduces a novel class of pesticide formulations that utilize modified cellulose nanofibers (CNFs) as a delivery system for antifungal agents, particularly copper nanoparticles (Cu NPs), to treat Cercospora leaf spot and potentially other plant diseases. The CNFs are chemically modified to graft active compounds—such as trimethylethylenediamine (TMEDA), aminobenzimidazole (ABZI), or humic acid (HA)—which serve as ligands for copper, resulting in CNFs-TMEDA-Cu, CNFs-ABZI-Cu, or CNFs-HA-Cu complexes. These modified nanofibers effectively bind to the plant leaf surface and provide a slow, controlled release of antifungal agents, enabling prolonged protection against pathogens.

Laboratory studies demonstrated that both CNFs-TMEDA-Cu and CNFs-ABZI-Cu significantly inhibit the growth of Cercospora beticola, with ABZI-enhanced nanofibers offering stronger performance even at lower copper concentrations due to their synergistic antifungal activity. Greenhouse tests showed successful disease suppression in inoculated sugar beet plants, and field trials confirmed that a single spray of CNFs-ABZI-Cu outperformed traditional multiple-spray chemical fungicide treatments. The CNF platform also allows for the incorporation of additional antifungal agents and supports environmentally responsible synthesis processes using water-based, solvent-free methods.

This delivery platform offers enhanced rain resistance, reduced fungicide runoff, and fewer required applications, marking a significant advancement in crop disease management through nanotechnology.

Benefits

• Rain-resistant: CNF matrices anchor fungicides on leaf surfaces, minimizing wash-off.
• Long-lasting protection: Controlled release of copper ions prolongs antifungal effectiveness.
• Synergistic efficacy: ABZI conjugation enhances antifungal activity, reducing required copper concentrations.
• Lower phytotoxicity: Demonstrated minimal plant damage at effective concentrations.
• Environmentally sustainable: Water-based synthesis reduces chemical waste and exposure.
• Scalable: Compatible with existing spray infrastructure and adaptable to other crops and pathogens.

Applications

• Treatment of Cercospora leaf spot in sugar beets
• Broad-spectrum fungicide delivery for other crops (e.g., soybeans, peanuts)
• Nano-enabled crop protection platforms
• Rainfast pesticide formulations for humid and wet climates
• Sustainable agriculture and integrated pest management (IPM) systems

Patent

This technology has a U.S. Patent Pending and is available for licensing/partnering opportunities.