The correct option is A Alternaria, Phytophthora
Early blight is caused by Alternaria
, while late blight is caused by Phytophthora
. Phytophthora infestans
is an oomycete, that causes the serious potato disease known as late blight or potato blight. The organism can also infect tomatoes and some other members of the Solanaceae. At first, the spots are gray-green and water-soaked, but they soon enlarge and turn dark brown and firm, with a rough surface. Alternaria solani
is a fungal pathogen, that produces a disease in tomato and potato plants called early blight. The pathogen produces distinctive "bullseye". Symptoms of early blight occur on fruit, stem and foliage of tomatoes and stem, foliage and tubers of potatoes.
Thus, the correct answer is option A.