Ana García-Villaraco1, Lamia Boukerma1,2,3, Jose Antonio Lucas1, Francisco Javier Gutierrez-Mañero1, Beatriz Ramos-Solano1. 1. Facultad de Farmacia, Universidad San Pablo-CEU Universities, P.O. Box 67, Boadilla del Monte, 28668 Madrid, Spain. 2. Laboratoire National de Recherche en Ressources Génétiques et Biotechnologies, ENSA (ES1603), Al Harrach 16131, Algeria. 3. Laboratoire de Protection et de Valorisation de Ressources Agro-Biologiques, Faculté SNV, Université Saad Dahleb Blida 1, Blida 09000, Algeria.
Abstract
AIMS: to discover the interrelationship between growth, protection and photosynthesis induced by Pseudomonas fluorescens N21.4 in tomato (Lycopersicum sculentum) challenged with the leaf pathogen Xanthomonas campestris, and to define its priming fingerprint. METHODS: Photosynthesis was determined by fluorescence; plant protection was evaluated by relative disease incidence, enzyme activities by specific colorimetric assays and gene expression by qPCR. Changes in Reactive Oxygen Species (ROS) scavenging cycle enzymes and pathogenesis related protein activity and expression were determined as metabolic and genetic markers of induction of systemic resistance. RESULTS: N21.4 significantly protected plants and increased dry weight. Growth increase is supported by significant increases in photochemical quenching together with significant decreases in energy dissipation (Non-Photochemical Quenching, NPQ). Protection was associated with changes in ROS scavenging cycle enzymes, which were significantly increased on N21.4 + pathogen challenged plants, supporting the priming effect. Superoxide Dismutase (SOD) was a good indicator of biotic stress, showing similar levels in pathogen- and N21.4-treated plants. Similarly, the activity of defense-related enzymes, ß-1,3-glucanase and chitinase significantly increased in post-pathogen challenge state; changes in gene expression were not coupled to activity. CONCLUSIONS: protection does not compromise plant growth; N21.4 priming fingerprint is defined by enhanced photochemical quenching and decreased energy dissipation, enhanced chlorophylls, primed ROS scavenging cycle enzyme activity, and glucanase and chitinase activity.
AIMS: to discover the interrelationship between growth, protection and photosynthesis induced by Pseudomonas fluorescens N21.4 in tomato (Lycopersicum sculentum) challenged with the leaf pathogen Xanthomonas campestris, and to define its priming fingerprint. METHODS: Photosynthesis was determined by fluorescence; plant protection was evaluated by relative disease incidence, enzyme activities by specific colorimetric assays and gene expression by qPCR. Changes in Reactive Oxygen Species (ROS) scavenging cycle enzymes and pathogenesis related protein activity and expression were determined as metabolic and genetic markers of induction of systemic resistance. RESULTS: N21.4 significantly protected plants and increased dry weight. Growth increase is supported by significant increases in photochemical quenching together with significant decreases in energy dissipation (Non-Photochemical Quenching, NPQ). Protection was associated with changes in ROS scavenging cycle enzymes, which were significantly increased on N21.4 + pathogen challenged plants, supporting the priming effect. Superoxide Dismutase (SOD) was a good indicator of biotic stress, showing similar levels in pathogen- and N21.4-treated plants. Similarly, the activity of defense-related enzymes, ß-1,3-glucanase and chitinase significantly increased in post-pathogen challenge state; changes in gene expression were not coupled to activity. CONCLUSIONS: protection does not compromise plant growth; N21.4 priming fingerprint is defined by enhanced photochemical quenching and decreased energy dissipation, enhanced chlorophylls, primed ROS scavenging cycle enzyme activity, and glucanase and chitinase activity.
Authors: Helena Martin-Rivilla; Ana Garcia-Villaraco; Beatriz Ramos-Solano; Francisco Javier Gutierrez-Mañero; Jose Antonio Lucas Journal: Plants (Basel) Date: 2020-12-08
Authors: José A Lucas; Ana García-Villaraco; Beatriz Ramos-Solano; Khalid Akdi; Francisco Javier Gutierrez-Mañero Journal: Plants (Basel) Date: 2022-05-05