Controlling Stored Products’ Pests with Plant Secondary Metabolites: A Review

Abstract

To date, only a handful of pesticides have been authorized by the European Council for the protection of stored grains. Resistance issues and ecotoxicity concerns necessitate the development of ecofriendly tools in that direction. In this review, we refer to the recent findings on plant extracts and pure plant-derived substances with promising biological activity and the potential to be used as biopesticides for stored products. The main aim of biopesticides is to be effective against target pests, without harming humans and the environment. Many plant species, among those reported herein, are part of the human diet, and are thus not harmful to humans. Edible plant extracts produced with inorganic solvents represent safe candidates for use as repellants, fumigants or contact pesticides. Cinnamon, rosemary, parsley, garlic, oregano and basil are found in products destined for human consumption but also display significant biological activities. Interestingly, cinnamon is one of the most widely tested botanical matrixes, exhibiting the best lethal effects on almost all insect and mite taxa reported herein (Acaroidea, Coleoptera and Lepidoptera), followed by basil and garlic. Prunus persica,Azadirachta indica A. Juss and Carum sp. seem to be very promising too as miticides and/or insecticides, with A. indica already being represented commercially by a plant-derived acaricidal formulation.