The invention relates to 5-alkyl-7-aminotriazolopyrimidines of the formula (I) and to the salts thereof. In said formula substituents have the following meanings: Rand Reach is a hydrogen atom or a group of alkyl, alcenyl, alcynyl, haloalkyl, cycloalkyl, phenyl or naphtyle, saturated, unsaturated or aromatic heterocycle having from five to six members which contain from one to four nitrogen atoms or one to three nitrogen atoms and one sulfur or oxygen atom, or Rand R can form together with a connecting them nitrogen atom a cycle of 5 to 6 members containing from one to four nitrogen atoms or from one to three nitrogen atoms and one sulfur or oxygen atom, R is a cycloalkyl or bicycloalkyl group, R, R and R can be substituted in conformity with a description, and X is an alkyl or alkyl halide group. The inventive methods and intermediary products necessary for producing said compounds, agents containing them and the use thereof for fighting against harmful mushrooms are also disclosed.