A large international research team has decoded the genome of the notorious organism that triggered the Irish potato famine in the mid-19th century and now threatens this season's tomato and potato crops across much of the US.

Published in the September 9 online issue of the journal Nature, the study reveals that the organism boasts an unusually large genome size more than twice that of closely related species and an extraordinary genome structure, which together appear to enable the rapid evolution of genes, particularly those involved in plant infection. These data expose an unusual mechanism that enables the pathogen to outsmart its plant hosts and may help researchers unlock new ways to control it.