Trends in molecular diagnosis and diversity studies for phytosanitary regulated Xanthomonas

30 Pág. Departamento de ​Protección Vegetal (INIA)
Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.
J.C. (Joana Costa) acknowledges R&D Unit Center for Functional Ecology-Science for People and the Planet (CFE), with reference UIDB/04004/2020, financed by FCT/MCTES through national funds (PIDDAC). V.C. acknowledges support of the University of Catania PIA.CE.RI. 2020–2022 Linea 2-Research Project MEDIT-ECO. J.C. acknowledges support from AEI by RTI2018-096018-R-C31 and FEDER. O.P. and I.R. acknowledge the European Union (ERDF, EAFRD) and Réunion regional council for support. J.F.P. acknowledges support from the Department of Life Sciences and Facility Management of the Zurich University of Applied Sciences (ZHAW) in Wädenswil. D.J.S. and J.G.V. also acknowledge joint funding by a grant from BBSRC, NERC, Defra, and the Scottish Government, under the Strategic Priorities Fund Plant Bacterial Diseases programme under the project ‘Xanthomonas plants diseases: mitigating existing, emerging and future threats to UK agriculture’ (BB/T010916/1 and BB/T010908/1). The APC was funded by COST (European Cooperation in Science and technology).