Mortality Assessment of Botanical Oils on Anastrepha fraterculus (Wiedemann, 1830) Applied in Fruits Under Laboratory Conditions

The objective of this study was to evaluate the effect of botanical oils on adult mortality and oviposition repellency of Anastrepha fraterculus in peach, apple and red cattley guava fruits. The fruits were treated by the dip method for 15 seconds with botanical oils of Ruta graveolens (0.05%), Cymbopogon citratus (1%), Cymbopogon winterianus (10%), Carapa guianensis (25%) and distilled water was used as a control. The experiments were carried out in a completely randomized design with twenty replicates. After being treated, the fruits were dried at room temperature, placed in separate plastic containers (750 mL) and transferred to a room at 25±2 °C. Each fruit was exposed to two fruit fly couples for 48 hours. After this period, the amount of dead insects was recorded. On apple fruits kept in containers with sterilized vermiculite, the effect of the treatments on A. fraterculus biology was evaluated for 36 days, and data were collected on the amount of pupae in the second generation. C. winterianus oil presented mortality rates of 100 and 80% of adults in peach and apple fruits, respectively. C. citratus oil caused a significantly different mortality rate compared to the control in peach fruits, whereas C. guianensis oil caused A. fraterculus mortality in red cattley guava and apple fruits. The mortality of A. fraterculus in fruits treated with R. graveolens oil did not differ from the control treatment. The botanical oils of C. winterianus and C. guianensis protected apple fruits by preventing A. fraterculus proliferation, and there was a significant reduction of the amount of pupae in the second generation. Botanic oils presented potential for suppression of fruit flies; however, further studies are necessary to test and make them feasible under field conditions.