title: Constitutive expression of pathogenesis-related proteins and antioxydant enzyme activities triggers maize resistance towards Fusarium verticillioides.
abstract: Fusarium verticillioides is a fungal pathogen of maize that causes ear rot and contaminates the grains with fumonisin mycotoxins. Breeding for resistance to Fusarium emerged as the most economic and environmentally safe strategy; therefore the discovery of resistant sources and effective molecular markers are a priority. Ears of resistant (CO441 and CO433) and susceptible (CO354 and CO389) maize lines were inoculated with F. verticillioides and the expression of pathogenesis-related (PR) genes (PR1, PR5, PRm3, PRm6) and genes that protect from oxidative stress (peroxidase, catalase, superoxide dismutase and ascorbate peroxidase) were evaluated in the kernels at 72h post inoculation. In addition, the oxidation level and the enzymatic activity of ascorbate-glutathione cycle, catalase, superoxide dismutase and cytosolic and wall peroxidases were investigated. The uninoculated kernels of the resistant lines showed higher gene expression and enzymatic activities, highlighting the key role of constitutive resistance in limiting pathogen attack. In contrast, the susceptible lines activated defensive genes only after pathogen inoculation, resulting in increased levels of H2O2 and lipid peroxidation, as well as lower enzymatic activities. The constitutive defenses observed in this study from seed could be profitably exploited to develop markers to speed up conventional breeding programs in the selection of resistant genotypes.
authors.affiliation: Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, Piacenza 29122, Italy. Electronic address: valentina.maschietto@unicatt.it.
authors.forename: Valentina
authors.initials: V
authors.lastname: Maschietto
authors.affiliation: Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, Piacenza 29122, Italy. Electronic address: alessandra.lanubile@unicatt.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lanubile
authors.affiliation: Dipartimento di Biologia, Università di Bari "Aldo Moro", via E. Orabona 4, Bari 70125, Italy. Electronic address: silvana.deleonardis@uniba.it.
authors.forename: Silvana De
authors.initials: SD
authors.lastname: Leonardis
authors.affiliation: Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, Piacenza 29122, Italy. Electronic address: adriano.marocco@unicatt.it.
authors.forename: Adriano
authors.initials: A
authors.lastname: Marocco
authors.affiliation: Dipartimento di Biologia, Università di Bari "Aldo Moro", via E. Orabona 4, Bari 70125, Italy. Electronic address: costantino.paciolla@uniba.it.
authors.forename: Costantino
authors.initials: C
authors.lastname: Paciolla
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D060467:Disease Resistance / Q000235:genetics; D005670:Fusarium / Q000254:growth & development / Q000502:physiology*; D018628:Gene Dosage; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005838:Genotype; D006861:Hydrogen Peroxide / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000235:genetics; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology*; D010940:Plant Proteins / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000382:microbiology*
chemical_list: D000975:Antioxidants; D010940:Plant Proteins; D012333:RNA, Messenger; D008315:Malondialdehyde; D006861:Hydrogen Peroxide
keywords: Defense systems; Fusarium verticillioides; Oxidative stress; Resistance; Zea mays