The effect of sulfobetaine on the activity of strobilurins and benzimidazole fungicides

Surfactants (adjuvants) are the substances often added to the spray tank, besides the pesticide formulation, whose role is to improve the performance of the pesticide or the physical properties of the spray mixture, or both. Adjuvants are not often used as fungicides themselves, however it is interesting to investigate if they can improve the fungistatic activity of the system they are included in. Therefore the main aim of this work was to determine the effect of addition of a newly obtained, never investigated before, sulfobetaine type surfactant to the fungicides on their final properties. In the in vitro experiment fungistatic activity of the surfactant and the system of surfactant with strobilurins and benzimidazole fungicides were evaluated. The tested surfactants were added to the liquid medium of Potato Dextrose Agar (PDA) at concentrations: 1, 10, 50 and 100 ppm. The organisms of Fusarium culmorum, Rhizoctonia solani, Microdochium nivale and Alternaria brassicae were used as indicators. The experiments have shown that the addition of the new surfactant studied to the medium resulted in inhibition of mycelium growth of all the tested fungi. The system with the surfactant and the fungicide was much more effective against the tested fungi than individual fungicides.