Potencial inseticida de extratos aquosos de Quassia amara L. (Simaroubaceae) no controle de Plutella xylostellaL. 1758 (Lepidoptera: Plutellidae)

Plutella xylostella, known as Diamondback moth, is aimportant pest for agricultural crops, especially plants in the Brassicaceae family. Due to the indiscriminate use of chemical insecticides, issues such as pest resistance and environmental contamination have increased. Seeking to find alternative controlmethods, this study evaluated the insecticidal potential of the aqueous extract of Quassia amara(EAQa), a plant from the Simaroubaceae family, on P. xylostella. The experiments were conducted under controlled conditions, using two extract concentrations (5% and 10%), where newly hatched P. xylostellalarvae were fed with organic cabbage discs treated with EAQa and distilled water. The individuals were monitored until the adult stage. The results showed that EAQa reduced the duration and viability of the larval stage, with a mortality rate of 60% at the 10% concentration. The extract also significantly reduced the longevity and fecundity of adults, as well as decreasing the survival of eggs. The study concluded that EAQa has promising insecticidal properties, interfering with the larval and reproductive stages of P. xylostella. This suggests that Q. amaramay be a sustainable alternative for controlling this pest, with less environmental impact compared to synthetic insecticides.