Biostimulation effects of rosemary essential oil on growth and nutrient uptake of tomato seedlings

Plant essential oils represent natural compounds that have a wide range of biologically activities on life systems. Various effects of essential oils on plant growth have been shown; however, their effects on nutrient uptake have not been yet assayed. In this study, effects of two concentrations of rosemary essential oil was evaluated on growth characteristics and nutrient uptake of tomato seedlings in a relatively lime soil and under greenhouse conditions. Treatments were foliar spray of 500 or 1000 ppm oil, soil application of 500 μL oil.kg−1 soil, and a no application control. The seedling growth was changed under essential oil applications particularly by 1000 ppm foliar spray. Foliar application of 1000 ppm essential oil reduced plant height, whereas it increased leaf SPAD value, shoot and root fresh weights, leaf soluble carbohydrates and nutrient concentration of nitrogen, potassium, magnesium, iron and zinc of leaves than control plants. Root fresh weight (but not other traits) was also higher under foliar application of 500 ppm oil or soil application of oil than control plants. The results indicate that rosemary oil has beneficial effects on nutrient uptake of tomato seedlings toward a better growth quality.