Protein HlpB gene capable of stimulating plant to perform allergic reaction

The invention relates to an hlpB gene which belongs to the technical field of biology, comes from plant pathogenic xanthomonas campestris and can stimulate the plant to perform allergic reaction. The sequence of the gene is shown in SEQ ID NO.1 and is 552bp in length; the hlpB gene is coded by 182 amino acids; the sequence of the amino acids is shown in SEQ ID NO.2; the hlpB protein does not contain cysteine and contains rich glycine, the isoelectric point is 5.28, the molecular weight is 19.5kDa, the protein has thermal instability, is sensitive to protease and can stimulate tobacco to perform allergic reaction. The hlpB gene obtained in the invention can be used as the gene resource for the breeding for disease resistance of plant and the hlpB protein can be used as the protein drug to stimulate the plant to have disease resistance.