Fuente: WIPO "essential oil or extracts" Some embodiments are directed to systems, methods, and formulations containing chitosan encapsulated nanoparticle pesticides. The nanoparticle solutions may contain one or more of tea tree oil, tea tree absolute, tea saponin oil, and tea saponin absolute, or other essential oils with concentrations ranging from 50 to 4000 ppm. The pesticides may be used to control Black Sigatoka and Yellow Sigatoka on banana plants and banana leaves. The nanoparticle formulations are encapsulated in a chitosan solution to create chitosan encapsulated slow-release pesticides. Some embodiments may include a filler, an extender, a wetting agent, a disintegrant, and a surfactant in the pesticide formulation.