brown rot gummosis vs brown rot

brown rot gummosis and brown rot both are nouns.

Word	Noun	Adjective	Verb	Adverb
brown rot gummosis	Yes	No	No	No
brown rot	Yes	No	No	No

As nouns, brown rot is a hypernym of brown rot gummosis; that is, brown rot is a word with a broader meaning than brown rot gummosis:

brown rot gummosis: disease of citrus trees caused by the fungus Phytophthora citrophthora
brown rot: any of certain fungous diseases of plants characterized by browning and decay of tissues

brown rot gummosis (noun)	brown rot (noun)
disease of citrus trees caused by the fungus Phytophthora citrophthora	any of certain fungous diseases of plants characterized by browning and decay of tissues