The Potato Plague: A Terribly Interesting Subject

Using natural history collections and herbarium specimens, Dr Jean Ristaino has identified and tracked the spread of P. infestans over 140 years.

Phytophthora infestans, was the causal agent of the potato “plague” that killed the Irish potato crop. In 1835, the HMS Beagle traveled to the island of Chiloé where Darwin discovered and sent back to Cambridge, wild species of potato. Darwin's interest in the potato and potato late blight spanned four decades.

We have used natural history collections and herbarium specimens to identify and track the spread of P. infestans. We identified the famine lineage in historic specimens, reputing a previous incorrect strain identification done only with modern lineages. The FAM-1 lineage caused both US and European historic outbreaks, was present globally for over 140 years and shared allelic diversity with the oldest specimens collected in Colombia. Population genomics data from historic P. infestans also links the ancestral FAM-1 lineage to P. andina, a sister species found in the Andes. We have developed a surveillance and mapping system ( USAblight.org) to report modern disease outbreaks and are developing new technologies that combine sensors, bioinformatics and geospatial surveillance tools to observe, contain and limit outbreaks of this important plant disease.

Our speaker, Dr. Jean Ristaino, is a William Neal Reynolds Distinguished Professor in the Department of Entomology and Plant Pathology at North Carolina State University. She works on the population genetics of the pathogen that caused the Irish faminePhytophthora infestans and studies the population structure and epidemiology of modern day and historic late blight outbreaks. Her lab studies the impact of migration, recombination and hybridization on the evolution of Phytophthora species. She developed pioneering research techniques for use of 150-year-old herbarium specimens to track epidemics.

She currently directs the Emerging Plant Disease and Global Food Security cluster at NC State. In 2018, she was awarded a Fulbright Research Scholar Award in at the University of Catania in Sicily and in 2022 was awarded a second Fulbright Award to work on Phytophthora in Ireland.

This talk is online and Zoom login details will be sent out two hours before the event start time.