0000000000305806
AUTHOR
Mónica Ordax
Survival Strategy of Erwinia amylovora against Copper: Induction of the Viable-but-Nonculturable State
Copper compounds, widely used to control plant-pathogenic bacteria, have traditionally been employed against fire blight, caused by Erwinia amylovora. However, recent studies have shown that some phytopathogenic bacteria enter into the viable-but-nonculturable (VBNC) state in the presence of copper. To determine whether copper kills E. amylovora or induces the VBNC state, a mineral medium without copper or supplemented with 0.005, 0.01, or 0.05 mM Cu2+ was inoculated with 107 CFU/ml of this bacterium and monitored over 9 months. Total and viable cell counts were determined by epifluorescence microscopy using the LIVE/DEAD kit and by flow cytometry with 5-cyano-2,3-ditolyl tetrazolium chlori…
Survival of Erwinia amylovora in rain water at low temperatures
E.G. Biosca , R.D. Santander, M. Ordax, E. Marco-Noales, B. Aguila, A. Flores and M.M. Lopez 1 Universidad de Valencia, Departamento de Microbiologia y Ecologia, Avenida Dr. Moliner 50, 46100, Burjassot, Valencia, Spain. 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Proteccion Vegetal y Biotecnologia, Carretera Moncada – Naquera, km 4.5, 46113, Moncada,Valencia, Spain. 3 Universidad de Valencia, Servicio Central de Soporte a la Investigacion Experimental, Avenida Dr. Moliner 50, 46100, Burjassot, Valencia, Spain.
Exopolysaccharides favor the survival of Erwinia amylovora under copper stress through different strategies.
Erwinia amylovora causes fire blight, a destructive disease of rosaceous plants very difficult to control. We demonstrated that copper, employed to control plant diseases, induces the "viable-but-nonculturable" (VBNC) state in E. amylovora. Moreover, it was previously reported that copper increases production of its main exopolysaccharide (EPS), amylovoran. In this work, the copper-complexing ability of amylovoran and levan, other major EPS of E. amylovora, was demonstrated. Following this, EPS-deficient mutants were used to determine the role of these EPSs in survival of this bacterium in AB mineral medium with copper, compared to their wild type strain and AB without copper. Tot…
Medfly Ceratitis capitata as Potential Vector for Fire Blight Pathogen Erwinia amylovora: Survival and Transmission
Monitoring the ability of bacterial plant pathogens to survive in insects is required for elucidating unknown aspects of their epidemiology and for designing appropriate control strategies. Erwinia amylovora is a plant pathogenic bacterium that causes fire blight, a devastating disease in apple and pear commercial orchards. Studies on fire blight spread by insects have mainly focused on pollinating agents, such as honeybees. However, the Mediterranean fruit fly (medfly) Ceratitis capitata (Diptera: Tephritidae), one of the most damaging fruit pests worldwide, is also common in pome fruit orchards. The main objective of the study was to investigate whether E. amylovora can survive and be tra…