Evaluation of Nerium oleander extracts against Pachycondyla sennaarensis (Hymenoptera, Formicidae) adults

Abstract

The Samsum (black) ant, Pachycondyla sennaarensis (Formicidae; Hymenoptera) is widely distributed throughout sub-Saharan Africa, and it is also the most common species of the family in southern Arabia. Samsum ant is very invasive and economically damaging and has become a big problem in Saudi Arabia and other distribution countries due to their aggressive nature, severe stings, and harm to agriculture, natural ecosystems, and human health. The physicochemical properties and varied effects against insect pests make plant extracts a potential alternative in the development of pesticides. In this study, the Nerium oleander leaves extract toxicity effects against P. sennaarensis adults. Exposure of P. sennaarensis adult to the oleander leaf extracts produced 96.7% mortality in the insecticidal bioassay, especially at 40% concentration. The mortality % ranged from 3.3-96.7% after 48hrs. The mortality percentage of the Samsum ant adults decreased by increasing exposure periods. The mortality % was highly negatively correlated with exposure times (R= - 0.80 to - 0.94; P = 0001) at 40 to 10% concentrations, respectively. The overall results of the current study suggest that the leaf extract of N. oleander may possess potential insecticidal properties, which could potentially be employed in pest management. The GC-MS investigation uncovered that N. oleander leaf extracts numerous bioactive compounds associated with plant secondary metabolites with their retention time (RT), and peak area %. We conclude that the N. oleander leaf extracts have the potential to be useful in managing insect pests, particularly Samsum ants, but that they must be handled and applied with extreme caution.