Chemical composition and herbicidal activity of Oregano (Origanum onites) essential oil on weeds and wheat

ABSTRACT Oregano essential oil (EO) is known as one of the EOs with the highest biological activity on target plant species. In this study, the inhibitory effects of different doses of oregano (Origanum onites L.) EO on the germination and seedling growth of some wheat cultivars and some problem weed species in wheat fields was investigated. For this purpose, both laboratory and pot experiments were carried out. Oregano EO obtained by steam distillation method and component analysis was made via GS/MS. Germination tests and pot experiments were carried out under controlled laboratory and greenhouse conditions. In the study, five wheat varieties, four for bread and one for durum, and five different weed species were used. The effects of different doses of oregano EO on the germination rate, viable plant rate, seedling length, and biomass of test plants were analyzed. According to the results, it was observed that oregano EO showed bioactivity on all species and cultivars included in the experiment. In terms of all parameters, it was concluded that wheat varieties showed higher resistance to oregano EO than weed species. These results show that oregano EO can be used to control some weed species that are a problem in wheat. GRAPHICAL ABSTRACT