Determination of the dose-response curve of the natural compound carvacrol for the control of the weeds Lolium rigidum and Sonchus oleraceus

Abstract

Synthetic herbicides have been the most widely used tool for weed control since their discovery and development in the mid-20th century. However, their continued use has led to the emergence of resistant weed biotypes, reducing their efficacy. They also provoked environmental problems, affecting non-target species, and causing crop stress. It is therefore necessary to look for new herbicides that could be effective in controlling weeds while also being environmentally friendly. The essential oils of some plants have compounds with phytotoxic properties, which can inhibit the germination and growth of weeds. Carvacrol is a monoterpene phenol found mainly in the essential oils of plants of the Lamiaceae family, with proven herbicidal activity. The aim of the present work was to obtain a dose-response curve of carvacrol on Lolium rigidum (monocotyledonous weed model) and Sonchus oleraceus (dicotyledonous weed model). The tests were carried out under greenhouse conditions, applying different doses of carvacrol on the weeds studied to obtain the dose-response curves. To assess the herbicidal activity of carvacrol, its efficacy on weeds were determined. S. oleraceus was more sensitive to carvacrol than L. rigidum. The dose-response curves obtained will be used in the future as a reference for field trials and for the study of synergistic interactions of carvacrol with other compounds.