Semiochemical-based attract-and-kill techniques in Stegasta bosqueella (Lepidoptera: Gelechiidae) management

The rednecked peanutworm, Stegasta bosqueella (Lepidoptera: Gelechiidae), is a key pest of Brazilian peanut. Due to its larval cryptic behavior and widespread occurrence in peanut crop, the adult stage could be considered in new control strategies. In this context, attract-and-kill strategy could be applied once this method combines an attractive semiochemical with a mortality agent and can be used in a formulation for direct pulverization. Therefore, our study evaluated the commercial attractant food source ACTTRA NOCTUIDEO™ (Isca Technologies™) for sampling and control of S. bosqueella during two peanut crop growing seasons. Adult and larval population of S. bosqueella was evaluated and a spatiotemporal analysis was applied to estimate the range of attractiveness to adults. Also, a behavior study was conducted to establish the optimal spraying time. Treatment application was performed with a backpack sprayer after realizing an increase in the abundance of adults caught in the sampling traps. We noticed that baited-traps are effective to attract and capture S. bosqueella adults. Furthermore, the best time to apply the attractive compound is after 5 pm and two applications one row distanced 50 m apart optimizes the attractiveness and mortality efficiency. We concluded that attract-and-kill strategy caused reduction of adults, larvae and plant injury whenever it was carried out immediately after observing an increase in adult abundance in the traps and when the best time and application range were adopted.