The active substance of new herbicide generation is N-(2-pirydyloamino) methylenobisphosphonic acid. Two strains Fusarium culmorum CB3 and Fusarium oxysporum XVI, isolated from soil treated with examined substance, were chosen to investigation of using it as a sole source of phosphorus, nitrogen or carbon in the concentrations at 1.0 mM. Interactions between the dominating strains of fungi and N-(2-pirydyloamino) methylenobisphosphonic acid, mycelium growth rate, the spore germinate index, the level chemical changes of N-(2-pirydyloamino) methylenobisphosphonic acid and pH were investigated after cultivation in mineral medium and its modifications. The results of growth kinetics of the studied Fusarium fungi in the presence of N-(2-pirydyloamino) methyle-nobisphosphonic acid, were expressed by dry weight [g·dm^-3]. Only Fusarium oxysporum XVI has been capa-ble to grow in acidic medium (pH 4.0) using N-(2-pirydylamino) methylene-bisphosphonic acid as an alterna-tive source of phosphorus. In these conditions the N-(2-pirydylamino) methylenebisphosphonic acid degrada-tion was carried out to utilize phosphorus compounds as a source of nutrient components for this strain. The presence of N-(2-pirydylamino) methylenebisphosphonic acid receded a growth rate of mycelium but did not have an effect on spores of tested fungi.