Potato blight (or potato late blight) is caused by a mildewlike fungus called Phytophthora infestans that can infect the potato foliage and its tubers. Although P. infestans is best known as a pathogen of the potato, this fungus also attacks the tomato and a number of other plants belonging to the family Solanaceae .

History

This disease first came to the attention of the world in the 1840s, when it suddenly appeared in Europe and caused the disastrous Irish potato famine. From Europe, the fungus spread all over the world. At first it was thought that the blight was simply due to rainy, cool weather, which caused the potato foliage to turn black and die. In 1863, a German scientist, Anton de Bary, proved that P. infestans was the cause of the disease, and through his pioneering work, deBary established the base for a new science: plant pathology...