The Cultigen reference article from the English Wikipedia on 24-Apr-2004
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Cultigen

Sponsorship the way you would do it
Cultigen is the name for organisms, especially cultivated plants like the edible banana, not known to have a wild or uncultivated counterpart in nature. It is a species that was domesticated (grown and selected by humankind) from so far back in antiquity, and has undergone such drastic transformation under prehistoric human selection, that the plant's ancestry is essentially unknown.

Etymology: culti(vation) + generated.