Insights from Sequencing Fungal and Oomycete Genomes: What CanWe Learn about Plant Disease and the Evolution of Pathogenicity?

Fungi and oomycetes are the causal agents of many of the world's most serious plant diseases and are unique among the microbial pathogens in being able to breach the intact surfaces of host plants, rapidly establishing infections that can have disastrous consequences for large-scale agricultural production. The ability to cause plant disease is not a common trait among the many saprotrophic and mutualistic fungal species, but it is a very widespread one, occurring throughout the fungal kingdom (James et al., 2006). Recently, there have been a number of studies published describing the genome sequences of a diverse set of fungi and oomycetes (Table 1), including one published in this issue of The Plant Cell (Hane et al., 2007), and this provides an opportunity to review what we have learned so far from sequencing the genomes of pathogenic and free-living fungi and also to look forward to the mass of genome sequence information that is likely to be generated in the next few years. The deployment of low-cost, high-throughput DNA sequencing technologies and large-scale functional genomics to eukaryotic plant pathogens will provide new insight into their biology and into the evolution of pathogenicity.