An object of the present invention is to provide a means for imparting resistance against pathogenic fungal, pathogenic bacterial, or pathogenic viral disease to agriculturally useful plants. The present invention relates to a bacterium belonging to the genus Azospirillum or the genus Herbaspirillum capable of imparting resistance against pathogenic fungal, pathogenic bacterial, or pathogenic viral disease to a host plant by living symbiotically within the plant, a method for controlling plant disease using the bacteria, and plants produced by such method.