CONTROL OF FIRE BLIGHT INFECTIONS WITH SYNTHETIC PEPTIDES THAT ELICIT PLANT DEFENSE RESPONSES
E. Badosa, L. Montesinos, C. Camó, L. Ruz, J. Cabrefiga, J. Francés, B. Gascón, M. Planas, L. Feliu, L. Montesinos
Antimicrobial peptides (AMPs) are reliable compounds to develop strategies for integrated plant disease management. These peptides can act directly against the pathogens and/or induce plant defense responses. In this work, 33 sequences including linear and cyclic peptides, linear and cyclic peptidotriazoles, and cyclic lipopeptides were tested for induction of plant defense. A first screening was carried out with BY2 tobacco cell cultures by determining the alkalinization and production of hydrogen peroxide. Peptides BP13, BP100, BP143 and BPC200W were slightly positive in these assays and were tested by RT-qPCR for expression of 10 defense-related genes in tomato, which are representative of the jasmonic acid, salicylic acid and ethylene pathways. BP13 and BPC200W induced overexpression of several genes that are also overexpressed by reference plant defense peptide elicitors. Plant assays with potted pear plants in the greenhouse confirmed the effect of peptides BP13 and BPC200W in controlling Erwinia amylovora infections, putatively through plant defense induction.