Late Blight

Disease of potato and tomato plants that is caused by the fungus Phytophthora infestans. The disease occurs in humid regions with temperature ranges of between 40° and 80° F (4° and 29° C); hot, dry weather checks its spread. Potato or tomato vines that are infected may rot within two weeks. The Irish potato famines of the mid-19th century were caused by late blight. The disease destroyed