Xylella fastidiosa invasion of new countries in Europe, the Middle East and North Africa: Ranking the potential exposure scenarios

Abstract

After the recent high-impact European outbreaks of Xylella fastidiosa (Xf), a xylem-limited plant pathogenic bacterium native to the Americas, this research aims to rank the risks of potential entry, establishment and spread of Xf in new countries across Europe, the Middle East and North Africa. A novel risk-ranking technique is developed, based on combining entry risk drivers (imported plants, direct flights and ferry connections) with risk factors related to establishment and spread (presence of potential insect vectors, vulnerable economic crops, alternative hosts and climate suitability) of this pathogen. This reveals that western European countries have the highest risk for entry, but that the Mediterranean basin runs the highest risk for establishment and spread of Xf. Lebanon in particular has the highest level of risk for Xf dispersal within its suitable territory. Countries without current outbreaks combining high risks of Xf arrival and establishment are mainly in the Mediterranean basin: Turkey is at the highest level of risk, followed by Greece, Morocco and Tunisia, which are ranked at the high level. The ranking model also confirms the vulnerability, in terms of invasion by Xf, of southern European countries (Italy, Portugal and Spain) in which the pathogen has already been reported. High summer temperatures in these southern countries are likely to be the significant determinant for the overall invasion process, while northern European countries have a high level risk for the arrival of the pathogen, but relatively low summer temperatures may limit establishment and spread of major outbreaks. In general, our study provides a useful approach for mapping and comparing risks of invasive non-native species and emerging pathogens between countries, which could be useful for regional horizon scanning and phytosanitary and biosecurity management.

Semi-Automatic Method for Early Detection of Xylella fastidiosa in Olive Trees Using UAV Multispectral Imagery and Geostatistical-Discriminant Analysis

“…The pathogen is currently spreading, and a serious risk exists that the bacterium may affect the whole of Europe, particularly all of the countries of the Mediterranean Basin [2]. The attention of producers and consumers to the largest area of olive cultivation in the world is therefore understandable: more than 2.5 million hectares in the Mediterranean basin.…”

Landscape restoration due to Xylella fastidiosa invasion in Italy: Assessing the hypothetical public’s preferences

“…This bacterium (Sequence Type 53) originating on coffee plants in Costa Rica is driven by an insect-vector, Philaenus spumarius, which is widely distributed in Apulia region (Bosco 2014;European Food Safety Authority 2015;Martelli et al 2015). Further, Frem et al (2020) predicted that this bacterium may invade new European and Mediterranean countries. However, the bacterium was also detected in Neophilaenus campestris and Euscelis lineolatus indicating the potential vectoring roles of these insects for the spread of the bacterium in Apulian region (Elbeaino et al 2014) while the spittlebug P. spumarius was the most abundant species found in orchards on both weeds and olive trees in Italy (Cornara et al 2017).…”

The potential direct economic impact and private management costs of an invasive alien species: Xylella fastidiosa on Lebanese wine grapes

“…Therefore, there is a continual risk of spreading Xylella fastidiosa across the world, which has led to recent serious outbreaks. Consequently, countries classified in the high-risk zone should constantly perform specialized pest risk analysis (PRA), implement preventive phytosanitary measures, and focus on enhancing inspection systems, while raising awareness about Xylella fastidiosa in order to reduce its economic and ecological impacts (Castrignanò et al 2020;Frem et al 2020) and ensure its early detection in asymptomatic plants and vectors (Riefolo et al 2021).…”