Release of multicomponent pheromones from porous fibres

Abstract

Surface engineering empowers a polymer exclusion net to serve dual functions: physical exclusion and pheromonal release, allowing for pest control in agricultural crops. In previous work, a net woven from porous fibres releasing simple, single-component alarm pheromones showed promising results in field tests. Here, this work is extended to release more complex pheromone mixtures, since many relevant insect reproduction pheromones are multicomponent mixtures. A novel in-situ method was developed to measure release of multicomponent pheromones using ultraviolet–visible spectroscopy (UV–Vis). Results demonstrate that all mixture components released at rates that are orders of magnitude greater than the minimum required pheromone dose of 0.05–0.09 mg · m⁻² · day⁻¹. The individual release rates vary between 11 and 189 mg · m⁻² · day⁻¹ at their maximum and depend primarily on component volatility. The release rates of certain components could also be increased or decreased slightly depending on interactions with other components. The observed shifts in evaporation rate were consistent with the theory of differential evaporation and previous work done on differential evaporation within porous media.