Impact of essential oils on the seed quality and the seed-borne pathogens of Althea officinalis

Abstract Background The production of medicinal plants depends on two major factors: the seed quality and the presence of seed-borne pathogens. The use of conventional plant protection products is not allowed in organic production, and therefore such production is highly risky. In an attempt to find an environmentally-safe solution and the equilibrium between the seed germination and the presence of fungal pathogens, the impact of essential oils of oregano, cinnamon, basil, caraway, mint, and lavender, at concentrations of 0.002 to 1% on Althea officinalis seeds aged one, two and three years, has been investigated. Results The treatment with lavender essential oil at the concentration of 0.02% was the most effective in three-year-old seeds. This treatment increased both seed germination and seedling growth by 13% and 24–35%, respectively. It also reduced the presence of seed-borne fungal pathogens in the range from 53 to 100%. Concuclusions The results indicate the benefits of certain essential oils in crop production. They may provide more sustainable and successful cultivation of marshmallow crops, especially in organic production.