Effectiveness of tailocins produced by Pseudomonas fluorescens SF4c in controlling the bacterial-spot disease in tomatoes caused by Xanthomonas vesicatoria

GODINO, AGUSTINA; PRÍNCIPE, ANALÍA; TORASSO, MILENKA; TORASSO, MILENKA; FISCHER, SONIA; FERNANDEZ, MARICRUZ; FISCHER, SONIA; FERNANDEZ, MARICRUZ; GODINO, AGUSTINA; PRÍNCIPE, ANALÍA

MICROBIOLOGICAL RESEARCH

ELSEVIER GMBH

Año: 2018 vol. 212-213 p. 94 - 102

0944-5013

The development of alternatives for the use of chemical pesticides for plant disease control is the present-day andongoing challenge for achieving sustainable agriculture. Pseudomonas fluorescens SF4c, native strain from wheat,produces tailocins (phage-tail-like bacteriocins) with antimicrobial activity against several phytopathogenicstrains. We thus investigated the efficacy of foliar application of these bacteriocins to control the bacterial-spotdisease in tomato caused by Xanthomonas vesicatoria Xcv Bv5-4a. The disease severity and incidence index werereduced by 44 and 36%, respectively; while the number of viable cells of X. vesicatoria Xcv Bv5-4a decreasedafter bacteriocin treatment. Furthermore, bacteriocin was effective in reducing bacterial-spot-disease symptomson tomato fruits even when applied 12 h after infection. Tailocin activity was not affected by abiotic influencessuch as adjuvant, light and temperature and, biotic factors such as apoplastic-fluids. In contrast, no antibacterialactivity of these tailocins was observed when the bacteriocin was exposed to extremely dry conditions. Finally,that no cytotoxic effects on mammalian cells were observed with this representative tailocins is highly significantand demonstrates the safety of such compounds in humans. All these findings indicate that the SF4c tailocinsrepresent an attractive alternative to copper-containing bactericides for use in the control of bacterial spot.