that are grown for their fruits remain to be investigated. Several are said to produce fruits as good as those of the cultivated tamarillo. These may hold potential as economic crops in their own right, or as germplasm sources for improving the tamarillo.
Fruit-bearing species deserving special studies include the following:
Cyphomandra casana (C. cajanumensis) Found growing wild on the edge of rain forests in the highlands of Ecuador, especially in the Loja Province. Like the tamarillo, the casana grows rapidly to a small tree, 2 m tall. Its large, furry, deep-green leaves make it an interesting ornamental, but it also produces heavy crops of mild-flavored fruits in about 18 months. The fruits are spindle shaped and golden yellow when ripe. They are sweet, juicy, and said to be rather like a blending of peach and tomato in flavor.
The casana seems to need cool growing conditions. Unlike the tamarillo, the casana fruit is a poor shipper. A breeding program for selection of firmer, larger, and better colored fruit could yield a fruit of commercial value. It deserves special attention from horticulturists and scientists as a source of genetic material for such qualities as nematode resistance, root rot resistance, fragrance, flavor, color, and yield.
Cyphomandra fragrans Compared with the tamarillo, this tree has greater tolerance to powdery mildew, a smaller and more robust stature, basal fruit abscission (the fruits break away clean without the stalk as found on tamarillos), and a greater degree of cold hardiness. Its fruits resemble small tamarillos, but have a thick and leathery orange skin. Like most solanaceous fruit, it is somewhat acid.
Cyphomandra hartwegi This species has an extensive natural range, but is not yet commercially cultivated. Apparently, it has not even been tested as a potential crop. It has a yellow berry about the size of a pigeon's egg.