The invention relates to a dispersion comprising at least one emulsion of an organic phase in an aqueous phase, said aqueous phase comprising a soluble salt content of at least 0.5 mol/l. The invention is characterized in that the aqueous phase contains at least one amphiphilic block copolymer, comprising at least one hydrophilic block, selected from copolymers which: (i) do not display macroscopic separation of phases in solution at 1% weight, in a mixture of water and KBr, the concentration of KBr being identical to that of soluble salt in the dispersion, at 20° C.; (ii) have a hydrophilic block(s)/hydrophobic block(s) mass ratio of between 40/60 and 95/5. The invention also relates to a method of producing said dispersion and phytosanitary formulations.
