potato mildew vs potato blight

potato mildew and potato blight both are nouns.

Word	Noun	Adjective	Verb	Adverb
potato mildew	Yes	No	No	No
potato blight	Yes	No	No	No

As nouns, potato mildew and potato blight are synonyms defined as:

Other synonyms of potato mildew include potato disease, potato mold, potato murrain.

potato mildew (noun)	potato blight (noun)
a blight of potatoes	a blight of potatoes