Genome sequence and genetic diversity of European ash trees

Ash dieback (a fungal disease) and the beetle Agrilus planipennis (a herbivore) are crushing ash tree populations in the Northern Hemisphere. To shed light on the genetic basis of the trees’ susceptibility and to understand the genetic diversity of these trees, Sollars et al. have sequenced one individual from the UK and annotated its genome. Through a deep sequence analysis, they compared the genome structure with other species for which genomes are already available, revealing an interesting set of genes shared among them. They also investigated the genetic diversity between different ash tree populations from Europe with the goal of finding the underlying genetic bases of tree susceptibility to fungal disease and herbivory. The authors found a correlation between ash dieback susceptibility and glycosides production (which defends against herbivory), indicating that it may be difficult to generate trees resistance to both fungal and herbivore attack. (Summary by Gaby Auge) Nature 10.1038/nature20786