Elucidating the mechanism of action of copper heptagluconate on the plant immune system against Pseudomonas syringae in tomato (Solanum lycopersicum L)

• Published in: Pest management science 2018-11, Vol.74 (11), p.2601-2607
• Main Authors: González‐Hernández, Ana I, Llorens, Eugenio, Agustí‐Brisach, Carlos, Vicedo, Begonya, Yuste, Teresa, Cerveró, Antonio, Ledó, Carlos, García‐Agustín, Pilar, Lapeña, Leonor
• Format: Article
• Language: English
• Subjects: Accumulation; Acids; Antioxidants; Bacteria; Copper; Copper - pharmacology; copper heptagluconate; Flowers & plants; Formulations; Gluconates - pharmacology; Immune system; induced resistance; Industrial plants; Leaves; Lycopersicon esculentum - immunology; Lycopersicon esculentum - microbiology; Organic chemistry; Pesticides; Phenolic compounds; Phenols; Plant Diseases - immunology; Plant Diseases - microbiology; Plant Immunity; Plant resistance; Polyphenols; Pseudomonas; Pseudomonas syringae; Pseudomonas syringae - drug effects; Reactive oxygen species; Solanum lycopersicum; Sugar Acids - pharmacology; Tomatoes
• ISSN: 1526-498X; 1526-4998
• DOI: 10.1002/ps.5050

BACKGROUND Phytopathogenic problems caused by the bacterial pathogen Pseudomonas syringae in tomato are becoming more serious due to the emergence of strains resistant to classical pesticides. This has led to research into new formulations with lower environmental problems. One of the most promising alternatives to the use of classical pesticides is the induction of natural plant defences. New formulations based on Cu complexed with heptagluconic acid induce plant innate defences and could be an alternative to classical treatments based on inorganic Cu against bacterial speck. To study the efficacy of this compound in tomato against P. syringae, we tested its systemic effect Applying the treatments via radicular. RESULTS Treated plants showed less infection development and lower number of viable bacteria in leaves. We also observed better performance of parameters involved in plant resistance such as the antioxidant response and the accumulation of phenolic compounds. CONCLUSION Results showed that soil drench applications can be highly effective for the prevention and control of bacterial speck in tomato plants, showing a reduction in symptoms of ∼ 50%. Moreover, application of Cu heptagluconate induced accumulation of the plant polyphenols caffeic and chlorogenic acids, and reduced the amount of reactive oxygen species in infected plants. © 2018 Society of Chemical Industry This study evaluates the effect of a copper heptagluconate formulation for the control of Pseudomonas syringae in tomato as an alternative to the use of inorganic copper.