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 characterised 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 DEG 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 a dispersion consisting in preparing an aqueous solution of copolymer and soluble salt and adding the organic phase thereto which, optionally, comprises an active material. Moreover, said invention relates to the use of such dispersions in relation to phytosanitary formulations.
