1. Combinations of active substances comprising a synergistically effective combination of at least one compound of the general formula (I): in which R & lt 1 & gt is hydrogen, amino, hydroxy, or optionally, once or repeatedly, the same or differently substituted alkyl of 1-6 carbon atoms , alkenyl of 2 to 6 carbon atoms, alkynyl of 2 to 6 carbon atoms or cycloalkyl of 3 to 6 carbon atoms, the substituents independently of each other being selected from the group consisting of halogen, cyano, nitro, hydroxy, alkoxy with 1- 4 atoms yi alkylthio with 1 to 4 carbon atoms, alkylsulfinyl with 1 to 4 carbon atoms, alkylsulfonyl with 1 to 4 carbon atoms, alkoxycarbonyl of 1 to 4 carbon atoms in alkoxy, alkylamino with 1 to 4 carbon atoms, dialkylamino with 1 to 4 atoms carbon in the corresponding alkyls, cycloalkylamino with 3 to 6 carbon atoms or alkylcycloalkylamino with 1 to 4 carbon atoms in the alkyl and 3 to 6 carbon atoms in the cycloalkyl, R represents hydrogen, alkyl of 1 to 6 carbon atoms, alkenyl of 2 to 6 carbon atoms, alkynyl with 2 to 6 carbon atoms, carbon atoms, cycloalkyl of 3 to 6 carbon atoms, alkoxy of 1 to 4 carbon atoms, alkylamino of 1 to 4 carbon atoms, dialkylamino with 1 to 4 carbon atoms in the corresponding alkyls, cycloalkylamino of 3 to 6 carbon atoms, alkoxycarbonyl with 1- 6 carbon atoms or alkylcarbonyl of 1 to 6 carbon atoms, R is hydrogen or corresponding if necessary, singly or repeatedly, the same or differently substituted alkyl of 1-6 carbon atoms, alkoxy of 1-6 carbon atoms, alkenyl of 2-6 carbon atoms, alkynyl of 2-6 carbon atoms,
