Approaches and Applications of Mentha Species in Sustainable Agriculture

The potential applications of the genus Mentha as natural pesticides and environmentally friendly postharvest treatments for agricultural products in sustainable agriculture are reviewed here. The non-commercialized Mentha species in Greece and the rest of the world are presented, and the possibility of their exploitation is discussed. Recent developments in successive methods of application-i.e., the formulation of Mentha extracts/oils in eco-friendly pesticides, fumigation, and the assessment of performance in field trials-are also reported. Several studies have shown that Mentha species in various forms (e.g., essential oil (EO), aqueous extract, fresh or dried plant material, compost, etc.), or in different cropping systems (e.g., crop rotation, intercropping system/cover crop, cultivation and incorporation as green manure) offer the potential to be used in agriculture, with the goal of managing plant pathogens (bacteria and fungi), animal pests (insects, acarines, and nematodes), weeds, and for the improvement of soil quality and productivity as well. Finally, several studies are presented concerning the enhancement of Mentha EOs effectiveness in agriculture, and to also overcome the limitations of their nature (being unstable when exposed to light and oxygen), by using a combination of EOs, or by developing novel formulations (microencapsulation). Taking into consideration all the abovementioned findings, it is evident that Mentha species could be used in sustainable agricultural systems for integrated pest management. This can be achieved utilizing them either directly as a crop, green manure, or compost, or indirectly by developing natural pesticides based on their EOs or extracts. Nonetheless, further field experiments must be conducted, to confirm the efficacy of various formulas on pests under crop conditions.