Morning Glories: 219 genes make the difference 2, 1 by dany12

dany12 wrote:
Ipomoea Nil Japonica is a multi-hybrid.
A cross between several natural climbers from three continents.
Asia, America, Africa.

Asia with : Ipomoea Nil Tokyo , Nil Beijing (China) and Nil Nepal all blue-purple.
America with : Ipomoea hederacea, as blue-purple.
Africa with : Ipomoea Nil Africa.

PURPLE is the basis colour.

ps: Nil Africa would be present early (1100 years ago)
My question: How a vine native of Guinea (West Africa) arrive in China? It is the enigma of the millennium!
Nil Africa