Home 9 Publications 9 Parallel host shifts in a bacterial plant pathogen suggest independent genetic solutions

Parallel host shifts in a bacterial plant pathogen suggest independent genetic solutions

Authors: Monica A. Donegan, Helvécio D. Coletta-Filho, Rodrigo P. P. Almeida
Date Published: 29/03/2023

While there are documented host shifts in many bacterial plant pathogens, the genetic foundation of host shifts is largely unknown. Xylella fastidiosa is a bacterial pathogen found in over 600 host plant species. Two parallel host shifts occurred—in Brazil and Italy—in which X. fastidiosa adapted to infect olive trees, whereas related strains infected coffee. Using 10 novel whole-genome sequences from an olive-infecting population in Brazil, we investigated whether these olive-infecting strains diverged from closely related coffee-infecting strains. Several single-nucleotide polymorphisms, many derived from recombination events, and gene gain and loss events separated olive-infecting strains from coffee-infecting strains in this clade. The olive-specific variation suggests that this event was a host jump with genetic isolation between coffee- and olive-infecting X. fastidiosa populations. Next, we investigated the hypothesis of genetic convergence in the host shift from coffee to olive in both populations (Brazil and Italy). Each clade had multiple mutations and gene gain and loss events unique to olive, yet no overlap between clades. Using a genome-wide association study technique, we did not find any plausible candidates for convergence. Overall, this work suggests that the two populations adapted to infect olive trees through independent genetic solutions.

Complete Circularized Genome Resources of Seven Strains of Xylella fastidiosa subsp. fastidiosa Using Hybrid Assembly Reveals Unknown Plasmids

Authors: María Pilar Velasco-Amo, Luis F. Arias-Giraldo, Miguel Román-Écija, Leonardo De La Fuente, Ester Marco-Noales, Eduardo Moralejo, Juan A. Navas-Cortés, and Blanca B. Landa

Date: 01/08/23

Xylella fastidiosa is a vascular plant pathogenic bacterium native to the Americas that is causing significant epidemics and economic losses in olive and almonds in Europe, where it is a quarantine pathogen. Since its first detection in 2013 in Italy, mandatory...

Induction of Defense Responses and Protection of Almond Plants Against Xylella fastidiosa by Endotherapy with a Bifunctional Peptide

Authors: Luís Moll, Aina Baró, Laura Montesinos, Esther Badosa, Anna Bonaterra, and Emilio Montesinos

Date: 08/08/23

Xylella fastidiosa is a plant pathogenic bacterium that has been introduced in the European Union (EU), causing significant yield losses in economically important Mediterranean crops. Almond leaf scorch (ALS) is currently one of the most relevant diseases observed in...