Phytopathology (2022) 112, 2296-2309

Noa Zecharia, Helena Krasnov, Miri Vanunu, Andreina Castillo Siri, Ami Haberman, Orit Dror, Lera Vakal, Rodrigo P.P. Almeida, Lior Blank, Dani Shtienberg and Ofir Bahar (2022)
Xylella fastidiosa outbreak in Israel: Population genetics, host range, and temporal and spatial distribution analysis
Phytopathology 112 (11), 2296-2309
Abstract: Diseases caused by the insect-transmitted bacterium Xylella fastidiosa have been reported in the Americas since the 19th century, causing diseases such as Pierce's disease of grapevine, almond leaf scorch (ALS), and citrus variegated chlorosis. In the last decade X. fastidiosa was reported from different parts of the world, most notably from southern Italy, infecting olives. In 2017, X. fastidiosa was reported to be associated with ALS symptoms in Israel. Here, we investigated the causal agent of ALS in Israel, its genetic diversity, and host range, and we characterized the temporal and spatial distribution of the disease. X. fastidiosa subsp. fastidiosa sequence type 1 was isolated from symptomatic almond trees and was used to infect almond and grapevine by mechanical inoculation. The pathogen, however, did not infect olive, peach, cherry, plum, nectarine, clementine, and grapefruit plants. Genomic analysis of local isolates revealed that the local population is derived from a single introduction and that they are closely related to X. fastidiosa strains from grapevines in California. Distribution analyses revealed that ALS did not expand from 2017 to 2019; however, since 2020, newly symptomatic trees appeared in the tested orchards. Symptomatic trees were located primarily in clusters, and symptoms tended to spread within rows. Our study confirms that X. fastidiosa is the causal agent of ALS in Israel and describes its genetic and host range characteristics. Although there is no clear evidence yet for the identity of the vectors in Israel, ALS spread continues to threat the almond and grapevine industries in Israel.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Rodrigo P.P. Almeida, Dani Shtienberg

Research topic(s) for pests/diseases/weeds:
surveys/sampling/distribution
population dynamics/ epidemiology

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Xylella fastidiosa	Almond (Prunus dulcis)	Israel