Ash dieback epidemic in Europe: How can molecular technologies help?

• Published in: PLoS pathogens Vol. 13; no. 7; p. e1006381
• Main Author: Downie, J Allan
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.07.2017; Public Library of Science (PLoS)
• Subjects: Abundance; Ascomycota - genetics; Ascomycota - pathogenicity; Ascomycota - physiology; Ascospores; Ash; Ash dieback; Ashes; Biodiversity; Biology and Life Sciences; Computer and Information Sciences; Dieback; Disease susceptibility; Divergence; Environmental conditions; Epidemics; Europe; Fertilization; Fraxinus - microbiology; Fruit bodies; Fungi; Gems; Gene expression; Gene sequencing; Genetic diversity; Genetic markers; Genomes; Infections; Leaves; Life cycle engineering; Life cycles; Markers; Microsatellites; Mycoses - epidemiology; Mycoses - genetics; Mycoses - transmission; Pathogens; Pearls; People and Places; Plant diseases; Plant Diseases - genetics; Plant Diseases - microbiology; Plant pathology; Plants; Population; Research parks; Ribonucleic acid; RNA; Single-nucleotide polymorphism; Spermatia; Subgroups; Summer; Trees; Europe
• ISSN: 1553-7374; 1553-7366; 1553-7374
• DOI: 10.1371/journal.ppat.1006381

Fertilization of these, probably by conidiosore spermatia, promotes the formation of mature fruiting bodies (F) that fire ascospores up into the air where they are carried to ash leaves to complete the life cycle. https://doi.org/10.1371/journal.ppat.1006381.g001 A life cycle that leads to pathogen diversity Unlike many fungal and oomycete plant pathogens that have caused major disease epidemics [6, 7], there is no evidence of clonal spread of H. fraxineus. Identification of genetic markers for low susceptibility using associative transcriptomics in ash Studies with a historical set of grafted clones of different lines of F. excelsior demonstrated that a few trees had low disease susceptibility over a wide range of environmental conditions, demonstrating a genetic basis for low susceptibility [25]. Two types of marker can be generated by RNA sequencing: single nucleotide polymorphisms (SNPs) and gene expression markers (GEMs) based on the abundance of different mRNA species. Based on genome sequencing [28] and microsatellite markers [29], most of the UK population of F. excelsior is genetically distinct from the Scandinavian population and this could explain why rates of susceptibility may be different. Since there is genetic divergence among different subgroups of ash within Europe [28, 29], it is possible that different subgroups of F. fraxineus within Europe could respond differently to this disease.