Activation of Brassica napus immune response by non-plant antimicrobial peptides

Abstract: Antimicrobial peptides (AMP) are small molecules found in all organisms showing antibacterial as well as antifungal activity against a wide range of pest species. Plant AMPs constitute important component of plant´s defence machinery, and besides their direct antimicrobial effect, some of them function also as endogenous elicitors of plant defence mechanisms. We focused on non-plantsynthetic AMPs as possible resistance inducers in oilseed rape (Brassica napus).The animal peptide chrysophsin and an insect peptide anoplin induced expression of defence genes regulated by salicylic acid and ethyleneand reactive oxygen species accumulation in treated cotyledons. Both peptides displayed fungistatic effect to Leptosphaeria maculans in vitro, however, only anoplin retarded symptom development in inoculated cotyledons.