Biological activity of essential oils of Myrtus communis (Myrtaceae, Family) and Foeniculum vulgare (Apiaceae, Family) on open fields conditions against corn aphids Rhopalosiphum maidis (Fitch, 1856) in western Algeria

Abstract

Within the framework of the development of the Algerian flora and considering the damage caused by Rhopalosiphum maidis, alternative solutions more respectful of the environment are necessary. Considering the important role of biopesticides of plant origin, this paper focuses on two plants, Myrtus communis L, belonging to the Myrtaceae family, and Foeniculum vulgare of the Apiaceae family. The aim is to deepen the knowledge on their chemical constituents and evaluate their insecticidal activity on heterogeneous natural populations of Rhopalosiphum maidis in cornfields. The essential oils (EOs) yields are 1.02% and 0.9% for Foeniculum vulgare and Myrtus communis. The chemical compounds identified by GC–MS are mainly monoterpenes and oxygenated monoterpenes. Anethole is the main component (84.60%) of F. vulgare, and α- -pinene (55.47%) and 1,8-cineole (28%) for M. communis. The toxicity tests performed in the field show that the EOs are toxic on heterogeneous populations of Rhopalosiphum maidis, with corrected mortality rates ranging from 70.24% to 88.13% after 4 and 5 days of treatment for each EO at concentrations of 5 mL/L and 6 mL/L.