Late Blight Tomato

"Leaf symptoms of late blight first appear as small, water-soaked areas that rapidly enlarge to form purple-brown, oily-appearing blotches. On the lower side of leaves, rings of grayish white mycelium and spore-forming structures may appear around the blotches. Entire leaves die and infections quickly spread to petioles and young stems. Infected fruit turn brown but remain firm unless infected by secondary decay organisms; symptoms usually begin on the shoulders of the fruit because spores land on fruit from above."

• Reference: http://www.ipm.ucdavis.edu/PMG/r783100211.html

Presence among species

Pathogen	Susceptible Host
Phytophthora infestans	Solanum bulbocastanum
Phytophthora infestans	Solanum demissum
Phytophthora infestans	Solanum tuberosum