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Potential Use of Essential oils from Four Tunisian Species of Lamiaceae: Biological Alternative for Fungal and Weed Control

Mohsen Hanana, Manel Ben Mansour, Methaq Algabr, Ismail Amri, Samia Gargouri, Abderrahmane Romane, Bassem Jamoussi and Lamia Hamrouni

Extremophile Plants Laboratory, Center of Biotechnology of Borj-Cedria, BP 901, 2050 Hammam-Lif, Tunisia.

Biological Department, Polytechnic Central School of Tunis, Tunisia

Department of Chemistry, Faculty of Applied Sciences, University of Hajjah, P.O.Box 80004, Yemen

National Center of Nuclear Sciences and Technologies, Pôle Technologique - 2020 Sidi Thabet BP 72. Tunisia

Plant Protection Laboratory, National Institute of Agronomical Research of Tunisia, Rue Hédi Karray, 2049, Tunisia

Laboratory of Applied Organic Chemistry, Semlalia, Cadi Ayyad University, Marrakech, Morocco

Laboratory of Chemistry, High Institute of Continue Education and Formation, 43 Rue de la Liberté, 2019 Le Bardo, Tunisie. Université Virtuelle de Tunis, Tunisia.

Laboratory of Forestry Resources Management and Valorization , National Institute of Rural Engineering, Water and Forest Researches, P.B. 10, 2080, Ariana, Tunisia

Abstract: The chemical composition of the essential oils (EOs) of four Lamiaceae (Thymus capitatus Hoff. et Link. , Rosmarinus officinalis L., Origanum vulgare L. and Mentha pulegium L.) growing wild in Tunisia was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Obtained results showed significant variations among the different species. The major constituents identified for each species were respectively carvacrol (69%) and δ-terpinene (17%) for T. capitatus, 1,8-cineole (41%) and α-pinene (24%) for R. officinalis, menthol (39%) and 1.8-cineole (17%) for M. pulegium , thymol (30%), p-cymene (30%) and δ-terpinene (27%) for O. vulgare . EO herbicidal effects were evaluated against three invasive weed species in most cultivated crops: Sinapis arvensis L., Phalaris paradoxa L. and Lolium rigidum Gaud. The study of herbicidal activity was carried out on seed germination and seedling vigor and growth. All tested EOs significantly inhibited the germination and growth of weeds in a dose dependent manner and their herbicidal activity could be attributed mainly to their high content in oxygenated monoterpenes. The antifungal ability of EOs was assessed by using disc agar diffusion against ten plant pathogenic fungi affecting crops and stored foods. The EOs displayed strong inhibitory effect on all tested fungi. Our results on EOs chemical composition and biological activities showed properties that could be valorized in managing biocontrol of weeds and plant fungi.