title: Is modulating virus virulence by induced systemic resistance realistic?
abstract: Induction of plant resistance, either achieved by chemicals (systemic acquired resistance, SAR) or by rhizobacteria (induced systemic resistance, ISR) is a possible and/or complementary alternative to manage virus infections in crops. SAR mechanisms operating against viruses are diverse, depending on the pathosystem, and may inhibit virus replication as well as cell-to-cell and long-distance movement. Inhibition is often mediated by salicylic acid with the involvement of alternative oxidase and reactive oxygen species. However, salicylate may also stimulate a separate downstream pathway, leading to the induction of an additional mechanism, based on RNA-dependent RNA polymerase 1-mediated RNA silencing. Thus, SAR and RNA silencing would closely cooperate in the defence against virus infection. Despite tremendous recent progress in the knowledge of SAR mechanisms, only a few compounds, including benzothiadiazole and chitosan have been shown to reduce the severity of systemic virus disease in controlled environment and, more modestly, in open field. Finally, ISR induction, has proved to be a promising strategy to control virus disease, particularly by seed bacterization with a mixture of plant growth-promoting rhizobacteria. However, the use of any of these treatments should be integrated with cultivation practices that reduce vector pressure by the use of insecticides, or by Bt crops.
authors: Department of Agricultural and Environmental Sciences, University of Milan, Via Celoria 2, 20133 Milano, Italy; CNR, Institute for Sustainable Plant Protection, Strada delle Cacce 73, 10135 Turin, Italy. Electronic address: franco.faoro@unimi.it.
authors: Franco
authors: F
authors: Faoro
authors: Department of Food, Environmental and Nutritional Sciences, Section of Chemistry and Biomolecular Sciences, University of Milano, Via Celoria 2, 20133 Milano, Italy.
authors: Franco
authors: F
authors: Gozzo
mesh_terms: D000613:Aminobutyrates / Q000494:pharmacology; D048271:Chitosan / Q000494:pharmacology; D054884:Host-Pathogen Interactions; D024101:Mitochondrial Proteins / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D010937:Plant Growth Regulators / Q000494:pharmacology; D057865:Plant Immunity / Q000187:drug effects*; D010940:Plant Proteins / Q000378:metabolism; D010942:Plant Viruses / Q000472:pathogenicity*; D010944:Plants / Q000187:drug effects / Q000276:immunology* / Q000382:microbiology; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism; D020156:Salicylic Acid / Q000494:pharmacology; D013830:Thiadiazoles / Q000494:pharmacology; D014774:Virulence; D000099188:Alternative Oxidase
chemical_list: D000613:Aminobutyrates; D048271:Chitosan; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010937:Plant Growth Regulators; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D020156:Salicylic Acid; D013830:Thiadiazoles; D000099188:Alternative Oxidase; C015700:benzo-1,2,3-thiadiazole
keywords: Alternative oxidase; Hypersensitive response; Induced systemic resistance; Plant growth-promoting rhizobacteria; Systemic acquired resistance