A pesticide, fungicidal, bactericidal, anti-pathogen or biocidal composition includes at least one biologically inert carrier; and at least one ferrite or at least one doped component including at least one fixed copper compound doped with at least one compound selected from the group consisting of iron compounds, zinc compounds, magnesium compounds, calcium compounds, and combinations and/or mixtures thereof. In one embodiment, the doped component has a particle size of about 0.5 nm to about 30 microns. A method for the control of pests includes the step of applying to the pests or their growth habitat the aforementioned composition. The method also includes the control of disease in citrus plants caused by vectors such as Psyllid nymphs, by applying the aforementioned composition to their growth habitat in citrus groves.