wheat rust vs Puccinia graminis

wheat rust and Puccinia graminis both are nouns.

Word	Noun	Adjective	Verb	Adverb
wheat rust	Yes	No	No	No
Puccinia graminis	Yes	No	No	No

As nouns, wheat rust and Puccinia graminis are synonyms defined as:

wheat rust (noun)	Puccinia graminis (noun)
rust fungus that attacks wheat	rust fungus that attacks wheat