Provided a method for controlling undesired vegetation at a plant cultivation site the method comprising the steps of providing at said site a plant that comprises at least one nucleic acid comprising a nucleotide sequence encoding a wild type or a mutated protoporphyrinogen oxidase (PPO) which is resistant or tolerant to a PPO inhibiting herbicide by applying to said site an effective amount of said herbicide. Further provided plants comprising wild type or mutated PPO enzymes and methods of obtaining such plants.
