Lulo

Solanum quitoense
Whole and transversely-cut fruit
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Solanales
Family:	Solanaceae
Genus:	Solanum
Species:	S. quitoense
Binomial name
Solanum quitoense Lam.
Synonyms
Solanum angulatum Ruiz & Pav. Solanum macrocarpon Molina (non L.: homonym) Solanum macrocarpon Pav. ex Dunal in DC. (nomen nudum, homonym) Solanum nollanum Britton Solanum quitense Kunth Solanum quitoense f. septentrionale (R.E.Schult. & Cuatrec.) D'Arcy Solanum quitoense var. septentrionale R.E.Schult. & Cuatrec.

Solanum quitoense, known as naranjilla (Spanish pronunciation: [naɾaŋˈxiʎa], "little orange") in Ecuador and Panama and as lulo ([ˈlulo], from Quechua) in Colombia, is a subtropical perennial plant from northwestern South America. The specific name for this species of nightshade means "from Quito."

The naranjilla plant is attractive, with large elongated heart- or oval-shaped leaves up to 45 cm in length. The leaves and stems of the plant are covered in short purple hairs. Naranjilla are delicate plants and must be protected from strong winds and direct sunlight. They grow best in partial shade.

The fruit has a citrus flavour, sometimes described as a combination of rhubarb and lime. The juice of the naranjilla is green and is often used as a juice or for a drink called lulada.

Within the genus Solanum, S. quitoense is a part of the subgenus Leptostemonum. Within this clade, S. quitoense belongs to the section Lasiocarpa. Other species within Lasiocarpa include: S. candidum, S. hyporhodium, S. lasiocarpum, S. felinum, S. psudolulo, S. repandum and S. vestissimum.

Other plants bear morphological similarity to S. quitoense, but they may or may not be closely related. Some of these plants are: S. hirtum, S. myiacanthum, S. pectinatum, S. sessiliflorum and, S. verrogeneum. Many of these plants, related or not, can be confused with S. quitoense. Furthermore, Solanum quitoense's physical traits vary from plant to plant, making identification challenging: at least three varietals (with spines, without spines, or a third variety known as baquicha, which features red-ripening fruits and smooth leaves) are known to occur. One characteristic that is unique to S. quitoense is the ring of green flesh within the ripe fruit. The only related fruit to have green flesh is a cultivated variant of S. lasiocarpum.

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Wikipedia