Silica coated insect proof screens for effective insect control in greenhouses

Abstract

Insect proof screens were coated with silica (SiO2) nanoparticles using the plasma coating process. The work studied whether a screen coated by SiO2 nanoparticles could be more effective on insects' control than a non-coated screen. Thus, the insect control properties of 25- and 40-mesh screens were studied. Besides, a series of experiments were performed to investigate the mechanical, optical, and airflow properties of different (25, 40, and 50) mesh screens coated or not with SiO2 nanoparticles. The air permeability of the screens was affected, while the mechanical and optical properties of the screens were not significantly affected by the SiO2 coating. Compared to 40- and 50-mesh non-coated screens, a 25-mesh SiO2-coated screen had 54% and 66% higher air permeability values, respectively. The mean number of aphids infesting the leaves and stems of the crop grown under a 25- or a 40-mesh SiO2-coated screen was up to 93% and 81% lower than those grown under the non-coated screens, respectively. The number of aphids found on plants grown under a 25-mesh SiO2-coated screen were significantly lower (about 80%) than those recorded under a 40-mesh non-coated screen. Based on the differences observed on screen's air permeability and on greenhouse ventilation models available in the literature, it was estimated that a greenhouse with a 25-mesh SiO2-coated screen will have 11.5% and 23.1% higher ventilation rate than a greenhouse with a 40- or 50-mesh non-coated screen, respectively. © 2022 IAgrE