title: Chemical products induce resistance to Xanthomonas perforans in tomato.
abstract: The bacterial spot of tomato, caused by Xanthomonas spp., is a very important disease, especially in the hot and humid periods of the year. The chemical control of the disease has not been very effective for a number of reasons. This study aimed to evaluate, under greenhouse conditions, the efficacy of leaf-spraying chemicals (acibenzolar-S-methyl (ASM) (0.025 g.L(-1)), fluazinam (0.25 g.L(-1)), pyraclostrobin (0.08 g.L(-1)), pyraclostrobin + methiran (0.02 g.L(-1) + 2.2 g.L(-1)), copper oxychloride (1.50 g.L(-1)), mancozeb + copper oxychloride (0.88 g.L(-1) + 0.60 g.L(-1)), and oxytetracycline (0.40 g.L(-1))) on control of bacterial spot. Tomatoes Santa Clara and Gisele cultivars were pulverized 3 days before inoculation with Xanthomonas perforans. The production of enzymes associated with resistance induction (peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and protease) was quantified from leaf samples collected 24 hours before and 24 hours after chemical spraying and at 1, 2, 4, 6, and 8 days after bacterial inoculation. All products tested controlled bacterial spot, but only ASM, pyraclostrobin, and pyraclostrobin + metiram increased the production of peroxidase in the leaves of the two tomato cultivars, and increased the production of polyphenol oxidase and β-1,3-glucanase in the Santa Clara cultivar.
authors.affiliation: Universidade Federal de Santa Catarina, SC, Brazil .
authors.forename: Adriana Terumi
authors.initials: AT
authors.lastname: Itako
authors.affiliation: Universidade Federal de Santa Catarina, SC, Brazil .
authors.forename: João Batista
authors.initials: JB
authors.lastname: Tolentino Júnior
authors.affiliation: Departamento de Proteção Vegetal, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil .
authors.forename: Tadeu Antônio Fernandes da
authors.initials: TA
authors.lastname: Silva Júnior
authors.affiliation: Departamento de Proteção Vegetal, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil .
authors.forename: José Marcelo
authors.initials: JM
authors.lastname: Soman
authors.affiliation: Departamento de Proteção Vegetal, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil .
authors.forename: Antonio Carlos
authors.initials: AC
authors.lastname: Maringoni
mesh_terms: D004156:Catechol Oxidase / Q000378:metabolism; D060467:Disease Resistance / Q000187:drug effects*; D005659:Fungicides, Industrial / Q000494:pharmacology*; D043326:Glucan 1,3-beta-Glucosidase / Q000378:metabolism; D018551:Solanum lycopersicum / Q000201:enzymology / Q000276:immunology / Q000382:microbiology*; D010447:Peptide Hydrolases / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D010650:Phenylalanine Ammonia-Lyase / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology*; D014974:Xanthomonas / Q000187:drug effects / Q000254:growth & development*
chemical_list: D005659:Fungicides, Industrial; D004156:Catechol Oxidase; D009195:Peroxidase; D043326:Glucan 1,3-beta-Glucosidase; D010447:Peptide Hydrolases; D010650:Phenylalanine Ammonia-Lyase
keywords: Solanum lycopersicum; bacterial spot; control; enzymes