Phytophthora infestans

Culprit of the Irish Potato Famine

Many may be familiar with the devastating story of the Irish Potato Famine that occurred in the mid 1800’s, but relatively few may realize that the organism that caused the tragedy, Phytophthora infestans, has proved to be a problem in recent years. For instance, an adaptation for resistance against a widely used

fungicide caused major loses in potato crops.  Some may also find it interesting to know that P. infestans is the microorganism which helped make plant pathology a science today.  Indeed, late blight was the first plant pathogen linked to a microorganism as the causative agent (Schumann and D’Arcy 2000).  For these reasons, learning about this plant pathogen is not only interesting but essential for protecting and sustaining life in many parts of the world.  The information provided on this site should prove useful in gaining a basic understanding of P. infestans.

Jacob Benrud

University of Wisconsin-La Crosse

Published April 27, 2007

Sporangia on a sporangiophore of Phytophthora infestans (1).

Photo Credits

1.  Courtesy W. E. Fry. Reproduced with permission from Schumann, G. L. and C. J. D’Arcy. 2000. Late blight of potato and tomato. The Plant Health Instructor. DOI: 10.1094/PHI-I-2000-0724-01.