autophyte vs plant life

autophyte and plant life both are nouns.

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

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

autophyte: 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 autophyte include flora, plant.

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