Solanum quitoense, known as naranjilla (, "little orange") in Ecuador, Costa Rica, Nicaragua, and Panama and as lulo (, from Quechua) in Colombia, is a tropical perennial plant from northwestern South America.
The lulo plant stands high, and has large elongated heart- or oval-shaped leaves up to in length covered in short purple hairs.
Solanum quitoense resembles and can be confused with certain other species of Solanum (some closely related to S. quitoense and others less so), including S. hirtum, S. myiacanthum, S. pectinatum, S. sessiliflorum and S. verrogeneum. Furthermore, S. quitoense is somewhat variable in appearance, making identification challenging: at least three varietals (with spines, without spines, and 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.
Pests and diseases
Solanum quitoense has limited potential in large-scale agriculture due to the plant's extreme vulnerability to pests and diseases when grown as a crop. One common type of infection is caused by the root-knot nematode.
Hybrids are a solution to the nematode pest problem. Its composition varies by growing conditions (region, genotype, cultivation).