Phytotoxic Effect of Invasive Essential Oil on Dicot and Monocot Species.

Spreading of the plant species in new areas is supported by the hypothesis in which chemicals produced by alien species are allopathic to native plants. A novel weapon hypothesis was tested by using essential oil of dangerous alien species in laboratory conditions. Aboveground plant material was collected in south-east part of Slovakia, dried and hydrodistilled for essential oil isolation. Dominant compounds as octyl acetate (62.6%), hexyl 2-metylbutyrate (10.7%), hexyl isobutyrate (7.5%) and hexyl butyrate (6.5%) were identified by GC-MS. Potential phytotoxic activity was tested on three dicot plant species garden cress ( L.), radish ( L.) and lettuce ( L.) and on one monocot plant species wheat L. Germination of the seeds of model plant species after influencing by different doses of essential oil of as well as the roots length was evaluated. L. and L. were generally not sensitive to applied doses of essential oil although a little stimulation effect at some concentrations prevailed over inhibition effect. Similarly, in monocot species L., stimulation was visible in both root length and root number at two or one highest doses, respectively.