The vector-borne bacterial pathogen Xylella fastidiosa is widely distributed in the Americas; in the last decade it has emerged as a serious threat for agricultural crops, natural environment and landscape in Europe. Following the first EU outbreak in 2013 in southern Italy, associated with a severe disease in olive trees, annual mandatory surveys are now in place in the Member States, leading to the discovery of bacterial outbreaks in different countries. Among the latest findings, an outbreak has been reported in the Italian region of Tuscany, with infections identified in seven different plant species. In this work, we report the isolation and the genetic characterization of isolates associated with this newly discovered outbreak. Multilocus sequence typing approach revealed the occurrence of isolates harbouring a new sequence type, denoted ST87, genetically related to strains of subsp. multiplex, but different from the genotypes of this subspecies previously characterized in Europe. Five cultured strains were successfully recovered from four of the seven host plants, an important achievement for advancing the studies on genomics and pathogenicity of these isolates and thus assess their potential threat for European agriculture.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Almeida, R. P., & Nunney, L. (2015). How do Plant diseases caused by Xylella fastidiosa emerge? Plant Disease, 99(11), 1457–1467.
Baldi, P., & La Porta, N. (2017). Xylella fastidiosa: Host range and advance in molecular identification techniques. Frontiers in Plant Science, 8, 944.
Bester, R., Jooste, A. E. C., Maree, H. J., & Burger, J. T. (2012). Real-time RT-PCR high-resolution melting curve analysis and multiplex RT-PCR to detect and differentiate grapevine leafroll-associated virus 3 variant groups I, II, III and VI. Virology Journal, 9, 219.
Chang, C. J., Garnier, M., Zreik, L., Rossetti, V., & Bové, J. M. (1993). Culture and serological detection of the xylem-limited bacterium causing citrus variegated chlorosis and its identification as a strain of Xylella fastidiosa. Current Microbiology, 27(3), 137–142.
Davis, M. J., Purcell, A. H., & Thomson, S. V. (1980). Isolation media for the Pierce's disease bacterium. Phytopathology, 70(5), 425–429.
Denancé, N., Legendre, B., Briand, M., Olivier, V., De Boisseson, C., Poliakoff, F., & Jacques, M. A. (2017). Several subspecies and sequence types are associated with the emergence of Xylella fastidiosa in natural settings in France. Plant Pathology, 66(7), 1054–1064.
EFSA (European Food Safety Authority). (2018). Scientific report on the update of the Xylella spp. host plant database. EFSA Journal, 16(9), 5408–5487. https://doi.org/10.2903/j.efsa.2018.5408.
EFSA PLH Panel (EFSA Panel on Plant Health), Jeger, M., Caffier, D., Candresse, T., Chatzivassiliou, E., Dehnen-Schmutz, K., Gilioli, G., Gregoire, J.-C., Jaques Miret, J. A., MacLeod, A., Navajas Navarro, M., Niere, B., Parnell, S., Potting, R., Rafoss, T., Rossi, V., Urek, G., Van Bruggen, A., Van der Werf, W., West, J., Winter, S., Almeida, R., Bosco, D., Jacques, M.-A., Landa, B., Purcell, A., Saponari, M., Czwienczek, E., Delbianco, A., Stancanelli, G., & Bragard, C. (2018). Scientific Opinion on the Updated pest categorisation of Xylella fastidiosa. EFSA Journal, 16(7), 5357–5361. https://doi.org/10.2903/j.efsa.2018.5357.
European Commission (2018). Commission database of host plants found to be susceptible to Xylella fastidiosa in the union territory. https://ec.europa.eu/food/ sites/food/files/ plant/docs/ph_biosec_legis _emergency_db-host-plants_update11.Pdf. Accessed 7 March 2019.
Francis, M., Lin, H., Cabrera-La Rosa, J., Doddapaneni, H., & Civerolo, E. L. (2006). Genome-based PCR primers for specific and sensitive detection and quantification of Xylella fastidiosa. European Journal of Plant Pathology, 115(2), 203–213.
Gori, A., Cerboneschi, M., & Tegli, S. (2012). High-resolution melting analysis as a powerful tool to discriminate and genotype Pseudomonas savastanoi pathovar and strains. PLoS One, 7(1), e30199.
Harper, S. J., Ward, L. I., & Clover, G. R. G. (2010). Development of LAMP and real-time PCR methods for the rapid detection of Xylella fastidiosa for quarantine and field applications. Phytopathology, 100(12), 1282–1288.
Hill, B. L., & Purcell, A. H. (1995). Acquisition and retention of Xylella fastidiosa by an efficient vector, Graphocephala atropunctata. Phytopathology, 85(2), 209–212.
Hopkins, D. L., & Purcell, A. H. (2002). Xylella fastidiosa: Cause of Pierce's disease of grapevine and other emergent diseases. Plant Disease, 86(10), 1056–1066.
Huson, D. H., & Bryant, D. (2005). Application of phylogenetic networks in evolutionary studies. Molecular Biology and Evolution, 23(2), 254–267.
Loconsole, G., Önelge, N., Yokomi, R. K., Abou Kubaa, R., Savino, V., & Saponari, M. (2013). Rapid differentiation of citrus hop stunt viroid variants by real-time RT-PCR and high resolution melting analysis. Molecular and Cellular Probes, 27, 221–229.
Marchi, G., Rizzo, D., Ranaldi, F., Ghelardini, L., Ricciolini, M., Scarpelli, I., Drosera, L., Goti, E., Capretti, P., & Surico, G. (2019). First detection of Xylella fastidiosa subsp. multiplex DNA in Tuscany (Italy). Phytopathologia Mediterranea, 57(3), 363–364.
Montes-Borrego, M., Loconsole, G., D’Attoma, G., De La Fuente, L., Saponari, M., & Landa, B. B. (2017). Rapid screening tests for the assignment of X. fastidiosa genotypes to a subspecies cluster. In Proceedings of the European conference on Xylella fastidiosa: Finding answers to a global problem, Palma de Mallorca, Spain, 13–15 November (Vol. 2017, p. 63).
Nunney, L., Yuan, X., Bromley, R., Hartung, J., Montero-Astúa, M., Moreira, L., Ortiz, B., & Stouthamer, R. (2010). Population genomic analysis of a bacterial plant pathogen: Novel insight into the origin of Pierce's disease of grapevine in the US. PLoS One, 5(11), e15488.
Nunney, L., Yuan, X., Bromley, R. E., & Stouthamer, R. (2012). Detecting genetic introgression: High levels of Intersubspecific recombination found in Xylella fastidiosa in Brazil. Applied and Environmental Microbiology, 78(13), 4702–4714.
Nunney, L., Hopkins, D. L., Morano, L. D., Russell, S. E., & Stouthamer, R. (2014). Intersubspecific recombination in Xylella fastidiosa strains native to the United States: Infection of novel hosts associated with an unsuccessful invasion. Applied and Environmental Microbiology, 80(3), 1159–1169.
Olmo, D., Nieto, A., Adrover, F., Urbano, A., Beidas, O., Juan, A., Marco-Noales, E., Lopez, M. M., Navarro, I., Monterde, A., Montes-Borrego, M., Navas-Cortés, J. A., & Landa, B. (2017). First detection of Xylella fastidiosa infecting cherry (Prunus avium) and Polygala myrtifolia plants, in Mallorca Island, Spain. Plant Disease, 101(10), 1820–1820.
Saponari, M., Boscia, D., Nigro, F., & Martelli, G. P. (2013). Identification of DNA sequences related to Xylella fastidiosa in oleander, almond and olive trees exhibiting leaf scorch symptoms in Apulia (southern Italy). Journal of Plant Pathology, 95, 668.
Saponari, M., Boscia, D., Altamura, G., Loconsole, G., Zicca, S., D’Attoma, G., Morelli, M., Palmisano, F., Saponari, A., Tavano, D., Savino, V. N., Dongiovanni, C., & Martelli, G. P. (2017). Isolation and pathogenicity of Xylella fastidiosa associated to the olive quick decline syndrome in southern Italy. Scientific Reports, 7(1), 17723.
Scally, M., Schuenzel, E. L., Stouthamer, R., & Nunney, L. (2005). Multilocus sequence type system for the plant pathogen Xylella fastidiosa and relative contributions of recombination and point mutation to clonal diversity. Applied and Environmental Microbiology, 71(12), 8491–8499.
Wells, J. M., Raju, B. C., Hung, H. Y., Weisburg, W. G., Mandelco-Paul, L., & Brenner, D. J. (1987). Xylella fastidiosa gen. Nov., sp. nov: Gram-negative, xylem-limited, fastidious plant bacteria related to Xanthomonas spp. International Journal of Systematic and Evolutionary Microbiology, 37(2), 136–143.
Wells, J. M., Raju, B. C., Nyland, G., & Lowe, S. K. (1981). Medium for isolation and growth of bacteria associated with plum leaf scald and phony peach diseases. Applied and Environmental Microbiology, 42(2), 357–363.
Yuan, X., Morano, L., Bromley, R., Spring-Pearson, S., Stouthamer, R., & Nunney, L. (2010). Multilocus sequence typing of Xylella fastidiosa causing Pierce's disease and oleander leaf scorch in the United States. Phytopathology, 100(6), 601–611.
The present work has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 727987 - XF-ACTORS “Xylella Fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategy”. The EU Funding Agency is not responsible for any use that may be made of the information it contains.
We gratefully acknowledge Leonardo De La Fuente for providing DNA from Temecula-1 strain and Françoise Poliakoff for providing DNA from CFBP 8416 strain.
We also wish to thank the curators of the PubMLST database and Dr. R. K. Yokomi for critically reading the manuscript.
The authors declare that ethical standards have been followed and that no human participants or animals were involved in this research.
The authors declare that they have no competing interests.
About this article
Cite this article
Saponari, M., D’Attoma, G., Abou Kubaa, R. et al. A new variant of Xylella fastidiosa subspecies multiplex detected in different host plants in the recently emerged outbreak in the region of Tuscany, Italy. Eur J Plant Pathol 154, 1195–1200 (2019). https://doi.org/10.1007/s10658-019-01736-9
- Xylella fastidiosa
- Sequence type
- Host plants