Effect of toxic baits on adult spotted-wing drosophila under laboratory conditions

Abstract

ABSTRACT Drosophila suzukii is an exotic pest identified in Brazil in 2013 that has the potential to cause quantitative and qualitative losses to small fruit crops. Its wide range of hosts and short life cycle combined with continuous fruit availability make its management challenging. Insecticide application is the main control strategy currently used; however, this control method is highly harmful to human health and the environment. The strategy of using toxic bait contributes to reductions in insecticide application in in terms of total area. Thus, this study aimed to assess the effect of toxic baits on adult Drosophila suzukii under laboratory conditions. Four bioassays with different treatments were conducted to test different ready-to-use toxic baits, as well as homemade and commercial bait formulations combined with insecticide. Twenty µL of each toxic bait were offered to 5 five-day-old pairs of D. suzukii for 2 hours. Adult mortality was assessed at 2, 4, 6, 8, 10, 12, 24, 48, 72, and 96 hours after exposure. All toxic baits caused mortality ranging from 10% to 65%. The toxic bait Droskidrink + 0.15% malathion + 0.3% sugar resulted in 65% adult mortality, denoting potential for evaluating the management of D. suzukii in semi-field and field studies.