The present invention relates to a composition comprising a first salt, which contains a first anionic pesticide (A1 ) and a cationic polyamine (B), and a second salt, which contains a second anionic pesticide (A2) and a cationic polyamine (B), wherein both salts contain the same cationic polyamine (B), and wherein the cationic polyamine comprises at least two amino groups. It further relates to a method for preparing said comprising the step of contacting the first salt and the second salt. In addition, the invention relates to a method of combating harmful insects and/or phytopathogenic fungi, which comprises contacting plants, seed, soil or habitat of plants in or on which the harmful insects and/or phytopathogenic fungi are growing or may grow, plants, seed or soil to be protected from attack or infestation by said harmful insects and/or phytopathogenic fungi with an effective amount of said composition. It also relates to a method of controlling undesired vegetation, which comprises allowing a herbicidal effective amount of said composition to act on plants, their habitat or on seed of said plants. Finally, the invention relates to seed comprising said composition.La presente invención se refiere a una composición que comprende una primera sal, que contiene un primer pesticida aniónico (A1) y una poliamina catiónica (B), y una segunda sal, que contiene un segundo pesticida aniónico (A2) y una poliamna catiónica (B), en donde ambas sales contienen la misma poliamina catiónica (B, y en donde la poliamina catiónica comprende al menos dos grupos amino. Además se refiere a un método para preparar dicha composicición, que comprende el paso de poner en contacto la primera sal y la segunda sal. Adicionalmente, la invención se refiere a un método para combatir insectos nocivos y/u hongos fitopatógens, que comprende poner en contacto las plantas, semillas, el suelo o hábitat de las plantas en y sobre las cuales los insectos nocivos y/u hongos fitopatógenos están creciend
