Irish potato famine pathogen identified

Scientists have used plant samples collected in the mid-19th Century to identify the pathogen that caused the Irish potato famine.

A plant pest that causes potato blight spread to Ireland in 1845 triggering a famine that killed one million people.

[It is interesting to learn  from this article that,  "Phytophthora infestans - which causes potato blight - emerged in the US in 1844, and spread to Europe the following year."]