Enhancement of the antifungal activity of thyme and dill essential oils against Colletotrichum nymphaeae by nano-encapsulation with copper NPs

Nanotechnology is a quickly growing field and have been actually used in a varied assortment of marketable products worldwide. Nanoencapsulation demonstrations the advantage of more efficient and targeted use of pesticides in an environmentally friendly way. Research and development in post-harvest nanotechnology can help to preserve food freshness and quality and prevent diseases in a relatively safer way. In this regard, essential oils (EOs) represent promising agents for reducing food decay and development of pathogen microorganisms. The overall aim of the present study was to encapsulate Iranian thyme (Thymus daenensis L) and dill (Anethum graveolens L.) EOs in copper nanoparticles (NPs) and to evaluate their antifungal activity against the phytopathogen Colletotrichum nymphaeae. Encapsulation of thyme and dill EOs with copper NPs resulted effective in reducing the mycelium growth even by 90% after 9 days treatment. Furthermore a strong inhibitory effect on conidia germination of C. nymphaeae was observed. SEM observations indicated that C. nymphaeae treated with EOs, copper NPs and encapsulated EOs, showed deformation in mycelial growth and hyphae twisting. In summary, these results showed that nano-encapsulation of EOs with NPs, using safe materials, increased the perspective of their effectiveness as new plant disease management strategies.