autophytic plant vs plant life

autophytic plant and plant life both are nouns.

Word	Noun	Adjective	Verb	Adverb
autophytic plant	Yes	No	No	No
plant life	Yes	No	No	No

As nouns, plant life is a hypernym of autophytic plant; that is, plant life is a word with a broader meaning than autophytic plant:

autophytic plant: plant capable of synthesizing its own food from simple organic substances
plant life: (botany) a living organism lacking the power of locomotion

Other hypernyms of autophytic plant include flora, plant.

autophytic plant (noun)	plant life (noun)
plant capable of synthesizing its own food from simple organic substances	(botany) a living organism lacking the power of locomotion