Fire blight: applied genomic insights of the pathogen and host

The enterobacterial phytopathogen Erwinia amylovora causes fire blight, an invasive disease threat to a wide-range of commercial and ornamental Rosaceae host plants. The response elicited by E. amylovora in its host during disease development is similar to the hypersensitive reaction typically leading to resistance in an incompatible host-pathogen interaction, yet no gene-for-gene resistance has been described for this host-pathogen system. Comparative genomic analysis has found an unprecedented degree of genetic uniformity among strains of E. amylovora suggesting that the pathogen has undergone a recent genetic bottleneck. The genome of apple, an important host of E. amylovora, has been sequenced creating new opportunities for the study of interactions between host and pathogen during fire blight development and for the identification of resistance genes. This review will include recent advances in genomics of both host and pathoge