After the first confirmed outbreak of Xylella fastidiosa in the European Union (EU), associated with an olive disease denoted olive quick decline syndrome, mandatory surveys are now carried out in the member States and inspections increased at EU entry points such as ports. Such activities led to the interception of X. fastidiosa-infected coffee plants in consignments originating from Central America. Similarly, the geographic expansion of the olive decline epidemic area of the Apulia region (southern Italy) prompted investigations to identify new host plants. Here we report the interception of three novel bacterial sequence types in Italy, based on multi-locus sequence typing, that cluster with different X. fastidiosa subspecies, illustrating the risk of the introduction of additional pathogen genetic diversity into Europe. In the epidemic area of Apulia, new foci as well as host plant species positive with X. fastidiosa, including cherry, myrtleleaf and rosemary, were found to be all infected with the same sequence type of this bacterium (ST53, or CoDiRO strain). This work highlights the limited knowledge of X. fastidiosa phylogenetic and phenotypic diversity, the risk of novel X. fastidiosa introductions via contaminated plant material, and corroborates other studies indicating that the Apulia epidemic emerged from a single introduction of this pathogen into the region.
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Almeida, R.P.P., & Nunney, L. (2015). How do plant diseases caused by Xylella fastidiosa emerge? Plant Disease, http://dx.doi.org/10.1094/PDIS-02-15-0159-FE.
Almeida, R. P. P., & Purcell, A. H. (2003). Biological traits of Xylella fastidiosa strains from grapes and almonds. Applied and Environmental Microbiology, 69, 7447–7452.
Almeida, R. P. P., Pereira, E. F., Purcell, A. H., & Lopes, J. R. S. (2001). Multiplication and movement of a citrus strain of Xylella fastidiosa within sweet Orange. Plant Disease, 85, 382–386.
Almeida, R. P. P., Blua, M. J., Lopes, J. R. S., & Purcell, A. H. (2005). Vector transmission of Xylella fastidiosa: applying fundamental knowledge to generate disease management strategies. Annals of the Entomological Society of America, 98, 775–786.
Almeida, R. P. P., Nascimento, F. E., Chau, J., Prado, S. S., Tsai, C. W., Lopes, S. A., & Lopes, J. R. S. (2008). Genetic structure and biology of Xylella fastidiosa causing disease in citrus and coffee in Brazil. Applied and Environmental Microbiology, 74, 3690–3701.
Amanifar, N., Taghavi, M., Izadpanah, K., & Babaei, G. (2014). Isolation and pathogenicity of Xylella fastidiosa from grapevine and almond in Iran. Phytopathologia Mediterranea, 53, 318–327.
Bergsma-Vlami, M., van de Bilt, J. L. J., Tjou-Tam-Sin, N. N. A., van de Vossenberg, B. T. L. H., & Westenberg, M. (2015). Xylella fastidiosa in Coffea arabica ornamental plants imported from Costa Rica and Honduras in The Netherlands. Journal of Plant Pathology, 97, 395.
Berisha, B., Chen, Y. D., Zhang, G. Y., Xu, B. Y., & Chen, T. A. (1998). Isolation of Pierce’s disease bacteria from grapevines in Europe. European Journal of Plant Pathology, 104, 427–433.
Cariddi, C., Saponari, M., Boscia, D., De Stradis, A., Loconsole, G., Nigro, F., Porcelli, F., Potere, O., & Martelli, G. P. (2014). Isolation of a Xylella fastidiosa strain infecting olive and oleander in Apulia, Italy. Journal of Plant Pathology, 96, 1–5.
Daugherty, M. P., Lopes, J. R. S., & Almeida, R. P. P. (2010). Strain-specific alfalfa water stress induced by Xylella fastidiosa. European Journal of Plant Pathology, 127, 333–340.
Elbeaino, T., Valentini, F., Abou Kubaa, R., Moubarak, P., Yaseen, T., & Digiaro, M. (2014). Multilocus sequence typing of Xylella fastidiosa isolated from olive affected by “olive quick decline syndrome” in Italy. Phytopathologia Mediterranea, 53, 533–542.
European and Mediterranean Plant Protection Organization (2015). EPPO reporting service. No. 9, Paris, 2015–09, 21p.
European Food Safety Authority (2015a). Scientific Opinion on the risks to plant health posed by Xylella fastidiosa in the EU territory, with the identification and evaluation of risk reduction options. EFSA Journal, 13, 3989[262 pp]. doi:10.2903/j.efsa.2015.3989.
European Food Safety Authority (2015b). Categorisation of plants for planting, excluding seeds, according to the risk of introduction of Xylella fastidiosa. EFSA Journal, 13, 4061. doi:10.2903/j.efsa.2015.4061.
Hudson, D. H., & Bryant, D. (2006). Application of phylogenetic networks in evolutionary studies. Molecular Biology and Evolution, 23, 254–267.
Jolley, K. A., Chan, M. S., Martin, C. J., & Maiden, M. C. (2004). mlstdbNet – distributed multi-locus sequence typing (MLST) databases. BMC Bioinformatics, 5, 86.
Kung, S. H., & Almeida, R. P. P. (2011). Natural competence and recombination in the plant pathogen Xylella fastidiosa. Applied and Environmental Microbiology, 77, 5278–5284.
Legendre, B., Mississipi, S., Oliver, V., Morel, E., Crouzillat, D., Durand, K., Portier, P., Poliakoff, F., & Jacques, M. A. (2014). Identification and characterisation of Xylella fastidiosa isolated from coffee plants in France. Journal of Plant Pathology, 96, S4.100.
Leu, L. S., & Su, C. C. (1993). Isolation, cultivation and pathogenicity of Xylella fastidiosa, the causal bacterium of pear leaf scorch disease in Taiwan. Plant Disease, 77, 642–646.
Loconsole, G., Boscia, D., Palmisano, F., Savino, V., Potere, O., Martelli, G. P., & Saponari, M. (2014). A Xylella fastidiosa strain with unique biology and phylogeny is associated with a severe disease of olive in Southern Apulia. Journal of Plant Pathology, 96, S4.38.
Martelli, G. P., Boscia, D., Porcelli, F., & Saponari, M. (2015). The olive quick decline syndrome in south-East Italy: a threatening phytosanitary emergency. European Journal of Plant Pathology. doi:10.1007/s10658-015-0784-7.
Martin, D., & Rybicki, E. (2000). RDP: detection of recombination amongst aligned sequences. Bioinformatics, 16, 562–563.
McElrone, A. J., Sherald, J. L., & Forseth, I. N. (2003). Interactive effects of water stress and xylem-limited bacterial infection on the water relations of a host vine. Journal of Experimental Botany, 54, 419–430.
Nunes, L. R., Rosato, Y. B., Muto, N. H., Yanai, G. M., Da Silva, V. S., Leite, D. B., Gonçalves, E. R., De Souza, A. A., Coletta-Filho, H. D., Machado, M. A., Lopes, S. A., & De Oliveira, R. C. (2003). Microarray analyses of Xylella fastidiosa provide evidence of coordinated transcription control of laterally transferred elements. Genome Research, 13, 570–578.
Nunney, L., Yuan, X. L., Bromley, R., Hartung, J., Montero-Astua, 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, e15488. doi:10.1371/journal.pone.0015488.
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, 4702–4714.
Nunney, L., Vickerman, D. B., Bromley, R. E., Russell, S. A., Hartman, J. R., Morano, L. D., & Stouthamer, R. (2013). Recent evolutionary radiation and host plant specialization in the Xylella fastidiosa subspecies native to the United States. Applied and Environmental Microbiology, 79, 2189–2200.
Nunney, L., Ortiz, B., Russell, S. A., Ruiz Sa, R., & Stouthamer, R. (2014a). The complex biogeography of the plant pathogen Xylella fastidiosa: genetic evidence of introductions and subspecific introgression in Central America. PloS One, 9, e112463.
Nunney, L., Schuenzel, E. L., Scally, M., Bromley, R. E., & Stouthamer, R. (2014b). Large-scale intersubspecific recombination in the plant-pathogenic bacterium Xylella fastidiosa is associated with the host shift to mulberry. Applied and Environmental Microbiology, 80, 3025–3033.
Nunney, L., Hopkins, D. L., Morano, L. D., Russell, S. E., & Stouthamer, R. (2014c). 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, 1159–1169.
Posada, D. (2008). jModelTest: phylogenetic model averaging. Molecular Biology and Evolution, 25, 1253–1256.
Purcell, A. H. (1997). Xylella fastidiosa, a regional problem or global threat? Journal of Plant Pathology, 79, 99–105.
Purcell, A. H., & Saunders, S. R. (1999). Glassy-winged sharpshooters expected to increase plant disease. California Agriculture, 53, 26–27.
Rathé, A. A., Pilkington, L. J., Gurr, G. M., Hoddle, M. S., Daugherty, M. P., Constable, F. E., Luck, J. E., Powell, K. S., Fletcher, M. J., & Edwards, O. R. (2012). Incursion preparedness: anticipating the arrival of an economically important plant pathogne Xylella fastidiosa Wells (proteobacteria: xanthomonadaceae) and the insect vector Homalodisca vitripennis (germar) (hemiptera: cicadellidae) in Australia. Austral Entomology, 51, 209–220.
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., Loconsole, G., Palmisano, F., Savino, V., Potere, O., & Martelli, G. P. (2014). New hosts of Xylella fastidiosa strain CoDiRO in Apulia. Journal of Plant Pathology, 96, 603–611.
Su, C. C., Chang, C. J., Chang, C. M., Shih, H. T., Tzeng, K. C., Jan, F. J., Kao, C. W., & Deng, W. L. (2013). Pierce’s disease of grapevines in Taiwan: isolation, cultivation and pathogenicity of Xylella fastidiosa. Journal of Phytopathology, 161, 389–396.
Swofford, D. L. (2002). PAUP*, Phylogenetic Analysis Using Parsimony (*and Other Methods). Version 4. Sunderland: Sinauer Associates.
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, 601–611.
This research was supported by grants from the Regional Plant Health Service of Apulia. We thank Alessandra Calzolari (Plant health Service Emilia Romagna, Italy), Valeria Gualandri (Fondazione Edmund Mach, S. Michele all’Adige (TN), Italy) and Anna Zelger (Provincia Autonoma di Bolzano − Alto Adige, Italy) for providing the coffee isolates. We thank Len Nunney for working with us on the new MLST alleles and STs. Work by RPPA was supported by the California Agriculture Experiment Station.
Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the authors.
Conflict of interest
The authors declare no conflict of interest.
G. Loconsole and M. Saponari contributed equally to this work
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Loconsole, G., Saponari, M., Boscia, D. et al. Intercepted isolates of Xylella fastidiosa in Europe reveal novel genetic diversity. Eur J Plant Pathol 146, 85–94 (2016). https://doi.org/10.1007/s10658-016-0894-x
- Xylella fastidiosa
- Olive disease
- Pierce’s disease, vector-borne