Commentary taken from Whalen et al. (1981): Solanum quitoense
is cultivated for its edible fruit in highlands of Colombia and Ecuador. It is used predominantly for juice and in preparation of refrescos with sugar and ice. The lulo
is one of the most delightful of tropical American fruits, with a flavor reminiscent of citrus, and is rich in Vitamin A and ascorbic acid (Romero-Castañeda, 1961). Cultivation of S. quitoense
is restricted by climatic requirements and susceptibility to root-knot nematode infection (Munier, 1962). It is most commonly grown in small plantings on newly cleared land.
Wild occurrences of S. quitoense
in Colombia and Ecuador are generally attributed to escape from cultivation. Volunteer plants are seen in disturbances and around habitations in regions where the species is cultivated. For reasons we do not understand, S. quitoense
has been most successful as a weed in Costa Rica and Panama, where it was introduced into cultivation in this century. A few collections from montane forests in Colombia may represent native populations (Cuatrecasas et al. 12111
from Norte de Santander and Cuatrecasas 15031
from the Cordillera Occidental in Valle). The regions in which these plants were found should be explored more fully as potentially important sources of germ plasm.
Heiser (1969) speculates that S. quitoense
was domesticated in highlands of central Colombia and transported by man to Ecuador and Peru. The basis for the argument is the existence of prickly forms and close relatives in the former region. The opposite direction of introduction, into Colombia from Ecuador, is postulated by Patiño (1962) and Schultes and Romero-Casteñeda (1962). Morphological data from Colombian and Ecuadorean plants point to a relative lack of variability in Ecuadorean S. quitoense.
The pattern observed may be due to founder effect associated with human dispersal of S. quitoense
southward in the Andes from a region of initial domestication in central Colombia as proposed by Heiser.
Heiser (1972) pointed out the close relationship of S. quitoense
to S. candidum,
a wide ranging species extending from Mexico to Peru. The morphological similarity between these taxa is great, and the differences between them are primarily in characters that would likely have been influenced by human selection during the process of domestication. In particular, S. quitoense
is unarmed or only sparsely prickly and has larger fruits with more readily deciduous hairs than S. candidum.
An additional difference is the green flesh of S. quitoense
fruits, an attribute of that species not found in any other members of section Lasiocarpa.