An object of the present invention is to provide a means for impartingresistanceagainst pathogenic fungal, pathogenic bacterial, or pathogenic viral diseasetoagriculturally useful plants. The present invention relates to a bacteriumbelonging tothe genus Azospirillurn or the genus Herbaspirillum capable of impartingresistanceagainst pathogenic fungal, pathogenic bacterial, or pathogenic viral diseaseto a hostplant by living symbiotically within the plant, a method for controlling plantdiseaseusing the bacteria, and plants produced by such method.