Duguetia lanceolata A. St.-Hil. (Annonaceae) essential oil: toxicity against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) and selectivity for the parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae)

Abstract

The fall armyworm (FAW) Spodoptera frugiperda is a polyphagous pest that is difficult to control due to populations resistant to various active ingredients. Thus, the objective of this study was to evaluate the toxicity of essential oils (EOs) from the organs of Annona neolaurifolia, Duguetia lanceolata, and Xylopia brasiliensis, against the FAW and its natural enemy, Trichogramma pretiosum. The most active EOs were those from the leaves and stem bark of D. lanceolata, which presented LD90 to S. frugiperda equal to 70.76 and 127.14 µg of EO/larvae, respectively. The major compounds in the EO of D. lanceolata (leaves) were β-caryophyllene and caryophyllene oxide. Although individually inactive against the FAW, when combined, those compounds reduced the insect’s probability of survival. However, the mortality was lower than that caused by EO. This result suggests that other components of EO contribute to the activity against FAW. Furthermore, the EO of the leaves from D. lanceolata presented low toxicity to the egg-larva stage of T. pretiosum, but was toxic to other phases. Thus, EO from D. lanceolata is potentially useful for developing new products to control S. frugiperda.