Scientists have decoded the DNA secrets of the notorious pathogen that caused the Irish potato famine, which led to the deaths of a million people.
The research, which involved the Scottish Crop Research Institute in Dundee, found the pathogen is highly adaptable and can change quickly.
The study will be used to try and curb the impact of the plant disease.
Scientists discovered that the organism boasts an unusually large genome size, more than twice that of closely related species, and an extraordinary genome structure.
Together, they enable the rapid evolution of genes, particularly those involved in plant infection.
Studies have revealed that the pathogen can outsmart its plant hosts because of its ability to change and can adapt to new plant hosts, including tomatoes or seemingly immune potato crops.
P. infestans thrives in cool, wet weather and can infect potatoes, tomatoes and other related plants, causing a "late blight" disease that can decimate entire fields in just a few days.
Long considered a fungus, it is now known to be a member of the oomycetes or "water molds," which are more closely related to brown algae than to fungi.
The study's findings, which involved researchers from all over the world, were published recently by Nature.