ASSESSMENT OF PLANT EXTRACTS TOXICITY IN GREENHOUSE AND FIELD EXPERIMENTS

Different native medicinal plants including lemon balm (Melissa officinalis), lavender (Lavandula angustifolia), and yarrow (Achillea millefollium) were extracted with ethanol. The plant extracts were assayed for their effects on different plant species (soybean, bean, rye, wheat and triticale) in greenhouse and field experiments. Seed germination by visual counting, ssedlings early growth by biometric measurements and resulted biomass (fresh and dried) by gravimetry were determined. All plant extracts at different concentrations inhibited seed germination, and seedling growth by comparison with the control. The degree of inhibition increased with increasing plant extracts concentration, suggesting that these extracts may contain allelochemicals which could interfere with seed germination and seedling growth of plants used in experiments.