halo blight vs halo spot

halo blight and halo spot both are nouns.

Word	Noun	Adjective	Verb	Adverb
halo blight	Yes	No	No	No
halo spot	Yes	No	No	No

As nouns, halo blight and halo spot are synonyms defined as:

Other synonyms of halo blight include bean blight.

halo blight (noun)	halo spot (noun)
a blight of bean plants	a blight of bean plants
a blight affecting the leaves of oats and other grasses