Abstract: The present invention discloses novel plant homologs of the Arabidopsis peptide atPEP1. atPEP peptides in Arabidopsis are involved in the amplification of defense pathways involved in innate immunity against microbial pathogens. Homologs to atPEP1 identified in soy, corn, rice, wheat, and canola sequence databases are potential sources for transgenes to enhance crop yield through resistance to biotic and/or abiotic stresses. Chimeric genes comprising sequences from mature and precursor plant defense response polypeptides from a given species, and from different species, as well as the encoded polypeptide sequences, are also described.