Development of an Unmanned Aerial System (UAS) integrated disperser for large-scale aerial deployment of Podisus maculiventris (Hemiptera: Pentatomidae) for biological control

The recent development of unmanned aerial systems (UAS) has provided new tools for the management of insect pests. This study was conducted to develop a system for real-time, safe, economical, and efficient aerial release of Podisus maculiventris (Hemiptera: Pentatomidae), a major natural enemy insect in various agroecosystems. The system was specifically designed for a large-scale aerial release of P. maculiventris where a visit-and-hand-release method is impractical. The objectives of this study were to (1) develop a mechanical system that could carry and release P. maculiventris aerially using a fixed-wing UAS that can cover a large area compared to rotary-wing UAS and (2) investigate the effect of aerial release on the performance of P. maculiventris. We developed an aerial release device which was externally mounted on the wings of fixed-wing UAS. The release system consisted of a holding chamber that was connected to a compressed air tank, which was triggered using a servo motor. After the deployment of three different stages of P. maculiventris, their mortality, body damage, survival, feeding, and oviposition were measured to determine the effect of aerial deployment.  The results showed no significant (P > 0.05) effects on survivorship, feeding, and oviposition on adult P. maculiventris but significantly (P < 0.05) high mortality was found in 3^rd and 5^th instars of P. maculiventris.  This study demonstrated that fixed-wing UAS equipped with a module for aerial release of P. maculiventris adults could be used for a large-scale deployment of natural enemy insects.