It is uncertain that the taste of the stems or tubers will prove widely appealing. The astringent effects of some types may hinder acceptance, but the selection of sweet types should eliminate this possibility.
Nearly everything remains to be done before this rustic crop's full potential can be characterized. Botanical investigations of the most basic kinds are needed. Because its cultivation is small scale, restricted to only a few areas, and declining, much genetic diversity has probably already been lost. Collections should be made to preserve the plant's variability. Seed should be conserved in germplasm banks. Variation among ecotypes should be sought and assessed; there is a particular need to find, multiply, and distribute elite genotypes.
Among agronomic features to be studied are water requirements, daylength sensitivity, and cold tolerance. It is uncertain at present if tuberization is dependent on daylength, temperature, moisture, some other factor, or a combination of these.
Complete studies of the nutritional qualities of all parts of the plant should be made. Amino acid analyses are particularly lacking. Also, the astringency should be studied. What causes it? Where is it found geographically? In what parts of the stems and tubers does it occur? How can it be eliminated? Also needed is more evaluation of the forage qualities of the foliage.
Botanical Name Mirabilis expansa Ruiz & Pavón
Family Nyctaginaceae (four o'clock family)
Pichincha (Ecuador): miso
Cotopaxi (Ecuador): tazo
Spanish: mauka, chagos, arricón, yuca inca, shallca yuca, yuca de la Jalca, pega pega, cushpe, arracacha de toro, camotillo
Origin. Although it didn't appear in the ethnobotanical literature until 1965, mauka is probably an ancient crop. Its wild ancestors are found in Peru, Bolivia, Ecuador, and Colombia.3