Assessing tank mixtures of pest behavior modulators and conventional insecticides in the management of soybean stink bugs

The utilization of pest behavior modulators in conjunction with conventional synthetic insecticides has emerged as a novel approach to enhance the efficacy of these applications. This integration involves the promotion of insect movement or the attraction of insects to treated areas, thereby optimizing the performance of the entire mixture. The present study aims to assess the effect of nine pest behavior modulators on the walking behavior of Euschistus heros (3rd instar nymphs and adults) using the automated computational tracking system (Ethovision^®). The findings revealed that Quimifol S450^® increased the total distance covered and sodium chloride (kitchen salt) reduced the walking speed of E. heros adults. Furthermore, physicochemical compatibility assessments employing the dynamic technique (with agitation) indicated that binary mixtures of all insecticides tested with Quimifol S450^® considerably increased the pH of the spray solution. Conversely, binary mixtures of insecticides with Atraksii^® exhibited a substantial increase in electrical conductivity. Moreover, laboratory tests (tarsal contact) and field trials (for two consecutive crop seasons), employing two conventional synthetic insecticides and four pre-selected pest behavior modulators, as well as their respective binary mixtures, demonstrated that the performance of stink bug control was diminished when sulfur-based dislodger Quimifol S450^® was mixed with acephate. Furthermore, the pest behavior modulators exhibited low activity after 15 min of insect exposure to treated surfaces. Our findings imply that the integration of homemade and commercial pest behavior modulators and conventional synthetic insecticides should be approached with caution, as potential antagonistic effects may be observed.