Nanostructured systems containing sexual pheromones aimed at controlling the brown stink bug Euschistus heros in soybean cultivation

Abstract

The brown stink bug (Euschistus heros) is an insect pest that has become increasingly important in soybean (Glycine max) production in Brazil. It can cause structural damage to seeds, leaf retention, tissue softening, protein dissolution and cell death, leading to an annual loss of more than 4.3 million tons of soybeans. Management with chemical insecticides has been the main alternative, however, pyrethroids, neonicotinoids and organophosphates have been used, that is, there are few tools available, in addition to the fact that these products can generate residues in food products, intoxication of end users, development of resistant insect populations and imbalance of beneficial insects. In the search for more sustainable forms of control, semiochemicals are an efficient and viable tool to be implemented in the integrated management of this pest. However, this method has limitations in terms of application, due to the ways in which they are delivered in the field, for example, in general, sexual pheromones are delivered in the field in static release systems such as rubber septa in traps, making their applicability difficult and with a short duration in the field, and requiring the collection of septa after use. It is at this point that this project has its importance, to minimize the limitations of application of semiochemicals in the field. The project focuses on exploring the use of nanosystems for the encapsulation of the sexual pheromone for the brown stink bug (the compounds 2,6,10 methyl trimethyltridecanoate and 2E, 4Z methyl decadienoate) developing systems for sustained release, focused on the use of natural matrices such as soy protein and nanostructured lipid transport systems with products such as soy lecithin and soy oil; as well as the use of 3D printing of prototypes, testing various polymer matrices with gum arabic and soy protein as support for the nanosystems. This proposal will be divided into three main stages: i) Preparation of the experimental design to evaluate and select the appropriate polymeric matrix to use as bioink in 3D printing; ii) preparation and characterization of the carrier nanosystems for the pheromones and iii) evaluation of the release profile and the influence of the nanosystems containing the pheromones on the attractiveness of the brown stink bug. From this proposal, it is expected to develop a system capable of being used within integrated pest management aimed at controlling the brown stink bug in soybeans and thus promoting more sustainable agricultural practices.