The objective of our studies was to develop effective, chemical methods of protecting narrow-leaved lavender (Lavandula angustifolia) against Phytophthora citrophthora with regard to their application. Under the laboratory conditions, activity of the tested agents was assessed on the basis of growth of P. citrophthora on a medium containing fungicides and the size of necrosis on the inoculated lavender shoots. In greenhouse tests growth of plants in the infested medium was evaluated. Laboratory research conducted indicated the highest effectiveness in limitation of P. citrophthora growth of Acrobat MZ 69 WG and Infinito 687,5 SC. In greenhouse tests, an evaluation of growth of lavender sprayed with Luna Senasation 500 SC and Python Consento 450 SC, carried out 3 weeks of cultivation, showed a significantly higher number of shoots in comparison with plants growing in the infested as well as non – infested control. All tested chemicals caused faster growth of the lavender. Change of the application method, i.e., foliar application of these products, substantially improved the growth results.

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