The lipopeptide surfactin triggers induced systemic resistance and priming state responses in Arachis hypogaea L.

RODRÍGUEZ, J.; TONELLI, M. L.; FIGUEREDO, M. S.; IBÁÑEZ, F.; FABRA, A.

EUROPEAN JOURNAL OF PLANT PATHOLOGY

SPRINGER

Año: 2018

0929-1873

Bioactive metabolites produced by multiplestrains of Bacillus spp. stimulate plant defense responses.Among these, the cyclic lipopeptide surfactinwas identified as an Induced Systemic Resistance (ISR)elicitor in different plant species. However, the underlyingmechanisms involved in the ISR elicitation and thepriming state costs in peanut plants (Arachis hypogaeaL.) remain unknown. In this work, we demonstrated theability of surfactin from B. subtilis to induce systemicresistance against Sclerotium rolfsii in peanut plants, andshowed that this response involves key characteristics ofpriming-mediated resistance defense. Application ofsurfactin significantly reduced S. rolfsii disease incidenceand severity on peanut plants, and an increasedshoot and root dry weight was observed in surfactin pretreatedand pathogen challenged plants compared tonon-treated challenged plants. In addition, peroxidaseactivity and phenolic compounds deposition underneaththe fungal infection zone were significantly higher insurfactin pre-treated and challenged plants than in nonsurfactintreated challenged plants. Collectively, resultsfrom this work indicate that ISR activity elicited by surfactin involves a priming defense state with lowfitness-related costs, providing an enhanced protectionagainst S. rolfsii in peanut plants.