Electrochemical Instability of Phosphonate-Derivatized, Ruthenium(III) Polypyridyl Complexes on Metal Oxide Surfaces

Plant parasitic nematodes are one of the worlds major agricultural pests, causing in excess of $157 billion in worldwide crop damage annually. Abamectin (Abm) is a biological pesticide with a strong activity against a wide variety of plant parasitic nematodes. However, Abms poor mobility in the soil compromises its nematicide performance because of the limited zone of protection surrounding the growing root system of the plant. In this study, we manipulated Abms soil physical chemistry by encapsulating Abm within the Red clover necrotic mosaic virus (RCNMV) to produce a plant virus nanoparticle (PVN) delivery system for Abm. The transmission electron microscopic and dynamic light scattering characterization of Abm-loaded PVN (PVNAbm) indicated the resultant viral capsid integrity and morphology comparable to native RCNMV. In addition, the PVNAbm significantly increased Abms soil mobility while enabling a controlled release strategy for Abms bioavailability to nematodes. As a result, PVNAbm enlarged the zone of protection from Meloidogyne hapla root knot nematodes in the soil as compared to treating with free Abm molecules. Tomato seedlings treated with PVNAbm had healthier root growth and a reduction in root galling demonstrating the success of this delivery system for the increased efficacy of Abm to control nematode damage in crops.