Abstract: Nucleotide sequences produced by mutation (also known as mutant nucleotide sequences) of C1 nucleotide sequences present in a pathogenic geminivirus genome in plants with one or more mutations capable of producing a dominant negative phenotype for the replication of the pathogenic virus, its diffusion in a plant, or its spread from one plant to another, especially through vectors such as insects, the mutant nucleotide sequences being capable of fully or partially inhibiting the replication and/or diffusion and/or spread of the pathogenic virus for producing phytopathogenic geminivirus resistant or tolerant transgenic plants.