Their most widespread common name is morning glory, but some species in related genera bear that same common name and some Ipomoea species are known by different common names. Those formerly separated in Calonyction[6] (
Greekκαλόςkalós "good" and νύξ, νυκτόςnúx, nuktós, "night") are called moonflowers.[5] The name Ipomoea is derived from the Greek ἴψ, ἰπός (íps, ipós), meaning "
woodworm", and ὅμοιος (hómoios), meaning "resembling". It refers to their twining habit.[7]
The genus includes
food crops; the
tubers of
sweet potatoes (I. batatas) and the leaves of
water spinach (I. aquatica) are commercially important food items, and have been for millennia. The sweet potato is one of the
Polynesian "
canoe plants", transplanted by settlers on islands throughout the
Pacific. Water spinach is used all over eastern Asia and the warmer regions of the Americas as a key component of well-known dishes, such as canh chua rau muống (Mekong sour soup) or
callaloo; its numerous local names attest to its popularity. Other species are used on a smaller scale, e.g. the whitestar potato (I. lacunosa) traditionally eaten by some
Native Americans, such as the
ChiricahuaApaches, or the Australian bush potato (I. costata). The peduncles or seed pods of
Ipomoea muricata are consumed as a delicacy in the
Indian state of
Kerala.
Moon vine (I. alba) sap was used for
vulcanization of the
latex of Castilla elastica (Panama rubber tree,
Nahuatl: olicuáhuitl) to
rubber; as it happens, the rubber tree seems well-suited for the vine to twine upon, and the two species are often found together. As early as 1600 BCE, the
Olmecs produced the balls used in the
Mesoamerican ballgame.[10]
The root called
John the Conqueror in
hoodoo and used in lucky and/or sexual
charms (though apparently not as a component of
love potions, because it is a strong
laxative if ingested) usually seems to be from I. jalapa. The
testicle-like dried tubers are carried as
amulets and rubbed by the users to gain good luck in
gambling or
flirting. As
Willie Dixon wrote, somewhat tongue-in-cheek, in his song "Rub My Root" (a
Muddy Waters version is titled "My John the Conquer Root"):
My pistol may snap, my mojo is frail
But I rub my root, my luck will never fail
When I rub my root, my John the Conquer root
Aww, you know there ain't nothin' she can do, Lord,
Humans use Ipomoea spp. for their content of medical and
psychoactive compounds, mainly
alkaloids. Some species are renowned for their properties in
folk medicine and
herbalism; for example, Vera Cruz jalap (I. jalapa) and Tampico jalap (I. simulans) are used to produce
jalap, a
cathartic preparation accelerating the passage of
stool. Kiribadu ala (giant potato, I. mauritiana) is one of the many ingredients of chyawanprash, the ancient
Ayurvedic tonic called "the elixir of life" for its wide-ranging properties.
The leaves of I. batatas are eaten as a vegetable, and have been shown to slow oxygenation of LDLs, with some similar potential health benefits to green tea and grape polyphenols.[11]
Other species were and still are used as potent
entheogens. Seeds of Mexican morning glory (tlitliltzin,
I. tricolor) were thus used by
Aztecs and
Zapotecs in
shamanistic and
priestlydivination rituals, and at least by the former also as a poison, to give the victim a "
horror trip" (see also
Aztec entheogenic complex).
Beach moonflower (I. violacea) was also used thusly, and the
cultivars called 'Heavenly Blue', touted today for their psychoactive properties, seem to represent an indeterminable assembly of
hybrids of these two species.
Though most often noted as "recreational" drugs, the
lysergamides are also of medical importance.
Ergonovine enhances the action of
oxytocin, used to still post partum bleeding. Ergine induces drowsiness and a relaxed state, so might be useful in treating
anxiety disorder. Whether Ipomoea species are useful sources of these compounds remains to be determined. In any case, in some jurisdictions, certain Ipomoea are regulated, e.g. by the
Louisiana State Act 159, which bans cultivation of I. violacea except for ornamental purposes.
Pests and diseases
Many
herbivores avoid morning glories such as Ipomoea, as the high
alkaloid content makes these plants unpalatable, if not
toxic. Nonetheless, Ipomoea species are used as food plants by the
caterpillars of certain
Lepidoptera (butterflies and moths). For a selection of diseases of the sweet potato (I. batatas), many of which also infect other members of this genus, see
List of sweet potato diseases.
Pollination
The species of Ipomoea interfere with each other's pollination. Pollen from different species compete in each other's reproductive processes, imposing a
fitness cost.[12]
^"Genus: Ipomoea L."Germplasm Resources Information Network. United States Department of Agriculture. 2007-10-05. Archived from
the original on 2010-05-28. Retrieved 2010-11-10.
^"Ipomoea L."Plants of the World Online. Board of Trustees of the Royal Botanic Gardens, Kew. 2017. Retrieved 15 July 2020.