This article was downloaded by: [Pontificia Universidad Javeria] On: 29 May 2013, At: 15:15 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK

Small Review Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/wzsf20 The Tamarillo (Cyphomandra betacea) Jaime Prohens a & Fernando Nuez a a Departamento de Biotecnología, Universidad Politécnica de Valencia, Camino de Vera 14,46022, Valencia, Spain Published online: 08 Nov 2010.

To cite this article: Jaime Prohens & Fernando Nuez (2001): The Tamarillo ( betacea), Small Fruits Review, 1:2, 43-68 To link to this article: http://dx.doi.org/10.1300/J301v01n02_06

PLEASE SCROLL DOWN FOR ARTICLE

Full terms and conditions of use: http://www.tandfonline.com/page/terms- and-conditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. The Tamarillo (Cyphomandra betacea): A Review of a Promising Small Crop

Jaime Prohens Fernando Nuez

ABSTRACT. The tamarillo is a small native to South America. It is grown for its edible fruit, which can be prepared in many different ways. The main regions of production are its native region as well as . Interest in the tamarillo as a potential new crop is in- creasing in many other -free climatic areas all around the world. There are three known types in the Andean region: red, yellow and purple. Tamarillo requires a sub-tropical climate, and can be grown in regions where crops are cultivated. Propagation by or cut- tings is common, with for efficient production differing accordingly to the propagation method. Tamarillo are susceptible to wind damage and should be planted in naturally sheltered areas or be protected by appropriate windbreaks. It is not seriously affected by pests and diseases, although the tamarillo mosaic (TaMV) causes significant damage in some areas of production. Tamarillo fruit can be picked when totally ripe or when the skin color is turning. Fruit picked with backward skin can then be treated with to induce . holds promise for crop improvement and in- creasing the adaptation and acceptance of this fruit into new production areas. This review paper outlines tamarillo production systems and the contributions and future prospects of germplasm enhancement, intra- Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 specific and interspecific hybridization, polyploidy and aneuploidy, mi- cropropagation and genetic transformation, selection and breeding for yield, quality, early harvesting and parthenocarpy for the development of new improved of tamarillo. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: Website: ]

Jaime Prohens and Fernando Nuez are affiliated with the Departamento de Bio- tecnología, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valen- cia, Spain. Small Fruits Review, Vol. 1(2) 2000 E 2000 by The Haworth Press, Inc. All rights reserved. 43 44 SMALL FRUITS REVIEW

KEYWORDS. Tree , cultivars, tamarillo mosaic virus, germ- plasm, hybridization, polyploidy, genetic transformation

INTRODUCTION

The tamarillo or tree tomato (Cyphomandra betacea (Cav.) Sendt.) is a small, fast-growing tree cultivated for its edible fruit. Tamarillo fruit can be consumed in many ways such as eaten raw as a dessert fruit, in salad, as an appetizer or prepared in a number of other ways. The tamarillo is such a versatile fruit that a book which only includes recipes for the tamarillo has been published (Bilton, 1986). It is valued by the food processing industry due to its high level of , which makes it specially suited for jams and preserves (Bohs, 1989b; Duke and duCellier, 1993) and because it has desirable properties for can- ning in syrup and for producing pulp, , sauce, baby food and in combination with milk products like yogurt, milk shakes and ice creams (Bohs, 1989a; Duke and duCellier, 1993; Hewett, 1993; de Vincenzi et al., 1995). Tamarillo is a promising crop for many frost-free, mild temperate areas throughout the world. Although it has been a relatively unex- ploited species, growing and shipping of tamarillos is increasing (Na- tional Research Council, 1989; Proctor, 1990). The tamarillo offers the opportunity to also diversify fruit production in many subtropical fruit production areas as a high value cash crop. Prices for premium quality fruits in select specialty markets in , North America and can reach $12 per kg. The tamarillo originated in South America, from where most Cy- Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 phomandra species are native. Genus Cyphomandra comprises some 30 species of bushes and small and is taxonomically closely related to the genus (Bohs, 1989a; Bohs, 1994). The area where C. betacea originated is not known, but some wild or natural- ized populations have been reported in southern and northeast- ern and may give an indication of its area of origin (Bohs, 1991; Brücher, 1977). Although there are some depictions in pre-Co- lumbian pottery (Towle, 1961), it seems that it was domesticated in relatively recent times. The fact that names for the tamarillo in its area of origin come from the Spanish or Portuguese language rather than from local languages seem to support this assumption (Heiser, 1969). The name tamarillo was coined in New Zealand in 1967 as the name Jaime Prohens and Fernando Nuez 45

was more marketable than the original name, tree tomato (Hewett, 1993). This fruit has been introduced in many subtropical areas throughout the world. The first account in the Old World dates back to 1799. In the late 19th century, it reached , , , , , , and New Zealand, where it was introduced from India (Bohs, 1989b). It is a commercially important crop in the highlands of Southern and Central America and in New Zealand. Production in South and Central America occurs in small for local consumption using a traditional system of manage- ment (Nuez et al., 1993). This results in intensely flavoured medium sized fruit that are marketed when fully ripe. Recently, new modern plantations have been established in these countries, mainly in Colom- bia, to produce larger size fruits for exportation (Osorio, 1992; Fisher and Ludders, 1994). In many cases fruits for export are harvested when they are not fully ripe which can result in excessively acidic fruits (Heatherbell et al., 1982; Prohens et al., 1996a). Few statistics are available on the acreage or production of tree tomato in this region. Nonetheless, it is notably important in many areas located from the high to medium altitudes of the . New Zealand has a cultivated area of some 200 ha and an annual production of approximately 2000 tons, 87% of which is exported to United States and Europe (Richard- son and Patterson, 1993; Eagles et al., 1994). Export market access and prices for tamarillo from New Zealand have greatly benefited from the marketing channels developed for . Australia also has some commercial plantations, although not as important as in New Zealand. Tamarillo is also grown in many other places such as Jamai-

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 ca, , Haiti, Canary Islands, , southern Asia and New Guinea (Symon, 1985; Azad-Thakur et al., 1988; Bohs, 1989b; Duke and duCellier, 1993). It can be grown and produce good yields in other frost-free geographical areas. It is possible to grow it successfully in areas with Mediterranean climates, such as the Mediterranean basin, California, Argentina and , where it has good prospects as a developing new fruit crop (Grau, 1994; Calabrese et al., 1995; Prohens et al., 1997). In many countries, including England and the United States specimens are sold as ornamental plants for (in frost- free areas) or as an indoor curiosity (Shaw, 1996). The tamarillo fruit are juicy, with a characteristically acidic taste. Prior to consumption and culinary use, the exocarp and the internal 46 SMALL FRUITS REVIEW

part of the mesocarp should be removed as they have a bitter taste. Tamarillos have interesting nutritional properties for the health con- scious consumer as they are low calorie fruit rich in A and C (Table 1). The tamarillo has been relatively unexploited through traditional plant breeding. Few crop improvement studies have been carried out and most attempts to introduce this crop into new environments have failed because they have relied on a single . This has restricted the opportunity to exploit variation for local adaptation. On the other hand, there is a serious concern about the loss of genetic diversity of this crop and wild related species (Sánchez-Vega, 1992; Nuez et al., 1999). In this paper we describe the main features of tamarillo, cultivation and handling along with a discussion of the potential of this crop from a plant breeding perspective.

DESCRIPTION AND REPRODUCTIVE BIOLOGY The tamarillo is a fast-growing tree, reaching a height of between 1 and 5 m. It is short-lived, with a life expectancy of only 5 to 12 years. The root system is shallow and not very extensive. In general, it forms a single trunk that is woody at the base and branches out at a height of 1.5 to 2 m to form a large spreading crown. The leaves are perennial, large (20 to 40 cm long and 20 to 35 cm wide), simple and have a strong musky smell. The flowers have a pink-white corolla and are fragrant. They are found in clusters of 10 to 50 flowers which hang from the branches on the current season’s growth and produce be- Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 tween 1 and 6 fruit. The fruit are usually elliptical, measuring between 4 to 8 cm in length and 3 to 5 cm in width (Figure 1), however, round and elongated types are also common. Fruits contain many seeds, which are larger than those of the tomato. The skin color may vary from yellow to purple, and occasionally has green or purple longitudi- nal stripes (Bohs, 1989b; Richardson and Patterson, 1993). Tamarillo plants start to produce fruit in the first or second year after transplanting. It is self-compatible and usually autogamous, but the flowers need to be shaken by the wind or visited by for to take place (Bohs, 1991; Pringle and Murray, 1991). If grown in conditions where flower vibration is limited, such as in a , fruit set can be very low (Sale, 1983a). Jaime Prohens and Fernando Nuez 47

TABLE 1. Composition of tamarillo fruits (from Morton, 1982; Rodríguez- Amaya et al., 1983; Pileri, 1989; Rathore, 1992; Romero-Rodríguez et al., 1994; Boyes and Strübi, 1997).

Characteristic Range Soluble solids content (_Brix) 10.0-13.5 pH 3.2-3.8 Total acidity (g/100 g) 1.0-2.4 Moisture (g/100 g) 81.0-87.8 Proteins (g/100 g) 1.5-2.5 (g/100 g) 0.05-1.28 Glucose (g/100 g) 0.5-1.0 Fructose (g/100 g) 0.7-1.2 Sacarose (g/100 g) 0.3-2.5 Fibre (g/100 g) 1.4-6.0 Citric acid (g/100 g) 1.27-1.80 Malic acid (g/100 g) 0.05-0.15 Quinic acid (g/100 g) 0.40-0.80 Ash (g/100 g) 0.60-0.83 A (I.U.) 540-2475 Ascorbic acid (mg/100 g) 19.7-57.8

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 (mg/100 g) 1.3-8.9 (mg/100 g) 290-347 (mg/100 g) 3.9-11.3 (mg/100 g) 19.7-22.3 Iron (mg/100 g) 0.40-0.94 Copper (mg/100 g) 0.05-0.20 Zinc (mg/100 g) 0.10-0.20 Manganese (mg/100 g) 0.10-0.20 Phosphates (mg/100 g) 33.9-65.5 48 SMALL FRUITS REVIEW

FIGURE 1. Tamarillo fruits.

CULTIVARS

Although the tamarillo shows a considerable variation for fruit characters, only a few cultivars have been commercially developed. Growers usually select healthy, high-yielding plants for harvest

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 or take cuttings for new plantations. In the Andean region, three tamarillo skin types, rather than culti- vars, are known (Figure 2):

S Red: This is the most commonly known type. It has reddish to orange skin when ripe, with faint, green to brown stripes. It is oval-shaped and the flesh is orange-colored. The fruit weighs be- tween 50 and 80 g. In New Zealand, 81% of exports are red types (Richardson and Patterson, 1993). S Yellow: It has bright yellow skin, with brown to green hardly no- ticeable longitudinal stripes. It is oval shaped and the flesh is yel- low. Fruit weight varies between 50 and 70 g. Jaime Prohens and Fernando Nuez 49

S Purple: This type is also known as ‘‘dark-red’’ or ‘‘black.’’ The fruits have a vivid dark red skin, with very faint green vertical stripes. It is round to oval in shape and the flesh is purple colored. The fruit usually weighs between 60 and 100 g. This latter type was the most widely grown in the plantations in New Zealand in 1982, and was obtained by selection in the 1920s. Re-selections of this type were the largest and best quality tamarillo at this time (Morton, 1982). The red and purple types are preferred by consumers in the United States and Europe as the color is more attractive even though taste is stronger and more acidic than that of the yellow type. This less acidic taste of the yellow fruit makes better preserves (Carnevali, 1974). Plant selection and breeding efforts have led to the development of several cultivars, especially in New Zealand and California (National Research Council, 1989; Mugleston, 1994; Calabrese et al., 1995). Among the yellow type, are the cultivars ‘Goldmine’, ‘Inca Gold’ and

FIGURE 2. The three tamarillo commercial types: Yellow (above left), red (above right) and purple (below centre). Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 50 SMALL FRUITS REVIEW

‘Egmont Gold’. Red type includes ‘Oratia Red’, ‘Solid Gold’, ‘Ecua- dorian Orange’, ‘Red Beam’, ‘Andys Sweet Red’, ‘Secombes Red’, ‘Red Delight’ and ‘Red Beau’. Finally, cultivars in the dark-red group include ‘Rothamer’, ‘Ruby Red’, ‘Holmes’ and ‘Kaitaia’.

ENVIRONMENTAL REQUIREMENTS The tamarillo is a subtropical plant and in the tropics grows better at medium or high altitudes in areas of neo-tropical montane forests. It has been found naturally growing in places with rainfall between 600 and 4000 mm, average annual temperatures of 15 up to 25_C, and a pH of 5 to 8.5. It grows at elevations between 1,500 and 3,000 m in , 300 and 900 m in Puerto Rico, 300 and 2,200 m in India, and around 1800 m in Haiti (Morton, 1982; Duke and duCellier, 1993). In colder climates it can be grown at lower altitudes. Although frost can kill the tamarillo plant, light frost will only damage the foliage and small branches and the plant will recover (Morton, 1982). The tamarillo can be successfully grown in areas where citrus is culti- vated (Carnevali, 1974). This would allow for the prospective cultiva- tion in many areas of the world. Tamarillo plants grow better in deep and fertile , although it is not a very exacting plant. For example, in Haiti, it is grown in lateritic soils that contain low levels of (Duke and duCellier, 1993). However the soil must be permeable, as tamarillo plants are not toler- ant to water-logging. Tamarillo’s branches are fragile, brittle and break easily when laden with fruit so the tamarillo should not be cultivated without protection

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 in windy areas. As these plants have a shallow root system, they can be blown over by strong winds if not protected sufficiently (Carnevali, 1974). Hailstones can damage the large tamarillo leaves and break the brittle branches, leaving the plant in a poor condition. However, dam- age to fruit is not as severe as in other crops due to their thick skin and strong attachment to the plant.

PROPAGATION The tamarillo can be grown from either seed or cuttings. Propaga- tion using seed is easy although the plantlets are very delicate during Jaime Prohens and Fernando Nuez 51

the weeks after germination. Plants propagated by seed can grow to a height of 1.5 to 1.8 m before branching out and are ideal in protected environments. These plants tend to be quite uniform in growth, al- though if they come from plantations with a range of cultivars or seedlings, cross pollination will occur and the seedlings can segregate for a range of characteristics (Pringle and Murray, 1991). Tamarillo cuttings root easily in peat or vermiculite although auxins can be used to improve rooting (Cazar et al., 1989). Plants grown from cuttings begin to branch out earlier, giving -like plants which are more suitable for exposed sites (Morton, 1982). The best cuttings to use for propagation are the basal and aerial suckers. They should be cut from healthy plants that are free of pathogenic . Plants are kept in the nursery until they reach a height of 1 to 1.5 m for plants grown from seed, and 0.5 to 1 m for plants grown from cuttings.

PLANTING AND GROWING SYSTEMS

The planting distances used in tamarillo production depend on the growing system. In New Zealand single row planting distances of 1 to 1.5 m between plants and 4.5 to 5 m between rows are recommended, or double rows with a planting distance of 2.5 to 3 m between rows, 2.5 m between plants, and 4.25 m between double rows (Morton, 1982; Sale, 1983a; Prohens et al., 1997; Osorio, 1992). In other places, such as the Andean region, where cultural practices are not mecha- nised, plantations are much more dense, with 1.2 to 1.5 m between plants. In regions affected by wind, dense planting is recommended, Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 and the plants staked to prevent them from being blown over. In many plantations the tamarillo is intercropped with citrus in such a way that the tamarillo’s quick growth to a productive size allows for profitable production for the first 4-6 years, after which time the tamarillo plants are removed (Carnevali, 1974). Greenhouse tamarillo production can be somewhat inconvenient due to its long life and extended growing cycle (Bohs, 1989b). Tamarillo plants can be grown in most soils, as long as suitable drainage is provided. Soil should be thoroughly prepared and plants planted on ridges if the soil is poorly drained (Sale, 1983a). Wind- breaks are advisable (Figure 3) and these should be erected before the plantations are established to protect the young plants (Morton, 1982). 52 SMALL FRUITS REVIEW

FIGURE 3. A dense young tamarillo plantation, protected by a windbreak.

PRUNING

Pruning techniques will vary depending on whether the plant has been grown from seed or cutting. Where plants have been grown from seed, the tip is cut when the plant reaches the suitable branch height, Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 usually 1.5 to 1.8 m. For plants grown from cuttings the lower branches must be pruned to achieve a crown at the desired height. Once the tree or bush shape has been formed, pruning levels are reduced to the removal of old or dead wood and previously fruited lateral branches. This pruning will encourage new shoot growth and future production sites. If the plant is not pruned, the tree will continue to grow and the fruit bearing branches will be on the outer extremes of the crown and more prone to wind damage. These outer crown branches also produce smaller, low quality fruit. Pruning should be done in spring. Early pruning will lead to early harvesting while later pruning will delay the harvest (Carnevali, 1974). Pruning also makes picking easier (Morton, 1982). Light pruning leads to moderate re- Jaime Prohens and Fernando Nuez 53

growth and an increased production of medium size fruit. Heavy prun- ing leads to vigorous regrowth (Figure 4), which gives lower produc- tion but larger fruit (Sale, 1983a; Richardson and Patterson, 1993). Suckers appearing on the trunk should be removed. When plants are grown in the greenhouse they should be heavily pruned to prevent excessive vegetative growth. Sometimes a renewal pruning is carried out in densely planted orchards when trees become too tall and make harvesting difficult. They are cut to a height of between 30 to 50 cm, to allow new shoots to grow about 8-10 months later. Branches may be propped up to prevent them from breaking under heavy crop loads.

IRRIGATION

The tamarillo tree needs a relatively continuous supply of water for it to be able to reach and maintain maximum production due to the shallow root system. During the dry season a lack of moisture in the soil can negatively influence plant growth, fruit size, and productivity.

FIGURE 4. Vigorous regrowth after heavy pruning. Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 54 SMALL FRUITS REVIEW

Conversely, water-logged soil should be avoided as this can lead to plant death.

NUTRITION

These annual rates per hectare are recommended in New Zealand, 170 kg of N, 45 kg of P, and 130 to 190 kg of K for high production levels (Richardson and Dawson, 1994). Both P and K are applied at the beginning in early spring, while several applications of N distributed throughout the year, are recommended (Carnevali, 1974; Sale, 1983a; Pileri, 1989). The recommended amounts of fertilizer per plant with 50% applications in spring and summer are 0.25-1 kg of a 5-6-6 N-P-K fertilizer, half of which should be applied in early spring and the other half in the summer (Morton, 1982).

SOIL MANAGEMENT

The field can either be kept weed free or allowed to maintain a ground cover that should be controlled to avoid competition with trees, especially in spring (Carnevali, 1974). Deep plowing is not possible due to the shallow root system, but it may be convenient to lightly plow to increase aeration. It is also possible to mulch the soil to increase moisture retention and suppress weed growth (National Re- search Council, 1989).

INSECTS AND RELATED PESTS Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 The tamarillo is not typically seriously affected by pests (Sale, 1983b), but on occasion considerable damage can be caused if not controlled. The main pests are: S . Various species of aphids attack the tamarillo, but the most important is Myzus persicae. Apart from the direct damage caused by this , aphids are also vectors of certain viruses that affect the tamarillo. S Greenhouse white-fly (Trialeurodes vaporariorum). If this pest is left uncontrolled it can cause significant leaf and fruit loss by re- ducing the yield by up to 75%. Jaime Prohens and Fernando Nuez 55

S Tomato worm (Neoleucinodes elegantalis). The larvae of this species feeds on the fruit and cause it to fall prematurely (Blank et al., 1991; Bohs, 1989b; Sale, 1983b).

Other less frequent pests that can also cause serious damage on occasion are: Green vegetable bug (Nezara viridula), green lopper caterpillar (Chrysadeixis sp.), thrips (Thrips sp. and Frankliniella oc- cidentalis), grass grub beetle (Costelytra zealandica), and fruit flies (Anasatrepha sp. and Carpolonchea pendula) (Blank et al., 1993; Duke and duCellier, 1993; Morton, 1982; Sale, 1983b). Snails and slugs can also eat leaves and young buds. All these pests can be controlled with the same chemical treatments used for other solanaceous crops. However, due to the lack of signifi- cant damage caused by these pests only a few treatments typically would be required (treatments against snails have only been necessary in Spanish experimental plantations surrounded by other horticultural crops during the last four years). Therefore this crop seems amenable to sustainable or integrated crop management systems.

NEMATODES

Few have been found to attack the tamarillo. Meloido- gyne incognita, M. java and M. hapla can cause serious damage in young trees (Cooper and Grandison, 1987; Velastegui and Fiallos, 1987) while another species has been recorded, Xiphinema diversicau- datum, as the vector of the Arabis mosaic virus (Sale, 1983b). Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013

FUNGAL DISEASES

The main disease afflicting the tamarillo is powdery mildew (Ery- siphe sp. and Oidium sp.). These fungi cause white spots that may lead to leaf loss if not controlled. Other less frequent fungal diseases affect- ing the tamarillo are Sclerotinia disease (Sclerotinia sclerotiorum), tamarillo leaf spot (Phoma exigua and Alternaria alternata), root rot (Phytophthora sp.), and anthracnose (Glomerella cingulata)(Sale, 1983b; Teakle et al., 1986; Velastegui and Ball, 1991; Duke and du- Cellier, 1993; Gupta and Choudhary, 1994). 56 SMALL FRUITS REVIEW

BACTERIAL DISEASES

Bacterial diseases are not a significant problem in tamarillo produc- tion, however, damage has been recorded of bacterial canker of toma- toes (Corynebacterium michiganense), bacterial blast (Pseudomonas syringae and P. solanacearum) and crown canker (Agrobacterium sp.) (Carnevali, 1974; Sale, 1983b; Saldarriaga et al., 1997).

VIRAL DISEASES

This crop is susceptible to a number of viruses that not only affect the tree’s vigour and yield, but can also cause blotches on the fruit lessening quality (Atkinson and Gardner, 1993; Eagles et al., 1994). The most harmful and dangerous of these viruses is the tamarillo mosaic virus (TaMV). This potyvirus is transmitted by aphids and causes chlorotic mottling and a severe discoloration of the fruit. In sampling of orchards in New Zealand, TaMV was found to be the most widespread virus (100% of plants infected) with the exception of some isolated orchards (Eagles et al., 1994). TaMV is one of the most limiting factors for increasing tamarillo production regions. Other viruses that have been found to affect the tamarillo, although losses caused by them are not as serious when compared to those caused by TaMV, are potato aucuba mosaic virus (PAMV), cucumber mosaic virus (CMV), alfalfa mosaic virus (AlMV), tomato spotted wilt virus (TSWV), arabis mosaic virus (ArMV), tobacco streak virus (TSV) and tomato aspermy virus (TAV) (Fletcher, 1987; Bohs, 1989b;

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Pliansinchai and Teakle, 1991; Eagles et al., 1994). There is no evi- dence that viruses affecting the tamarillo can be transmitted by seed, therefore reproduction using seeds rather than cuttings is a measure for reducing their spread. Notably, the tamarillo is immune to tobacco mosaic virus (TMV) and potato virus Y (PVY) (Pliansinchai and Teakle, 1991).

PHYSIOLOGICAL ABNORMALITIES

Occasionally, small, semi-transparent, hard, irregular stones are found in the tamarillo flesh. These stones contain large amounts of Jaime Prohens and Fernando Nuez 57

sodium and calcium, probably in the form of silicates, borates, alumi- num-magnesium-oxygen complexes, aluminates, or magnesium ox- ides, as well as small amounts of tin, copper, chromium, iron and (Morton, 1982). These stones are probably formed as a consequence of cultivating the tamarillo in mineral-rich soils like lat- eritic soils in the tropics, as they do not appear in trees cultivated in other soils (Prohens et al., 1997).

YIELDS The tamarillo plant will produce fruit two years after sowing, and reach peak production in the third or fourth year (Rotundo et al., 1981). If well managed, it can live and produce for 10 to 12 years. The tamarillo produces heavy crops (Figure 5) and at the peak of produc- tion can produce about to 20 to 30 kg of fruit per year. In New Zealand, commercial yields reach 15 to 17 t/ha (National Research Council, 1989).

HARVESTING In climates with little annual climatic variation, the tamarillo flow- ers and sets fruit throughout the year, so harvesting occurs through the whole year. However, in climates with seasonal changes, flowering and fruit set only takes place in spring with fruit ripening in autumn or winter. Ripening is not simultaneous and several harvests must be done. Tamarillos are picked when fully colored. Fruit can be picked when

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 they are at the turning stage (when the green color of the skin begins to change and the characteristic skin color begins to show) and then treated with ethylene to stimulate ripening (Figure 6) (El-Zeftawi et al., 1988; Prohens et al., 1996a). This early picking and subsequent ripening reduces the risk of crop failure, increases earli- ness and concentrates harvesting as it allows harvesting to be ad- vanced by up to one month (Prohens et al., 1996a).

POSTHARVEST Tamarillos can be stored for about 12 to 14 weeks at 3.5 to 4.5_C. At higher temperatures, postharvest diseases multiply rapidly. One of 58 SMALL FRUITS REVIEW

FIGURE 5. Tamarillo plant laden with fruits. Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013

the main causes of postharvest loss is bitter rot, a Colletotrichum sp. Applications of postharvest fungicides greatly reduce the number of fruit affected. Another alternative for postharvest disease control is to dip the fruit in water at 50_C for 10 min (Yearsley et al., 1988). Polythene films can be used to reduce water loss and maintain fruit quality (Carnevali, 1974). Packaging usually consists of wooden or cardboard boxes containing one tray of tamarillos or preformed plastic trays with 3 to 8 fruits. Jaime Prohens and Fernando Nuez 59

FIGURE 6. Postharvest tamarillo ripening (EF1 = fruits harvested when green, EF2 = fruits harvested when turning; 0, 250, 500, and 750, respectively, the ethephon dose applied (in mg/l)).

POTENTIAL IMPROVEMENT THROUGH BREEDING STRATEGIES

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Unfortunately, up to now, selection and breeding programs in tama- rillo have been scarce. Most studies have consisted in selecting the best material among a group of accessions and there are no details available on the inheritance of characters of interest. However, there is evidence which indicates that breeding can contribute effectively to giving more prominence to this crop.

GERMPLASM ENHANCEMENT

The first step in breeding a neglected crop like the tamarillo should be a germplasm screening to identify the most interesting accessions. 60 SMALL FRUITS REVIEW

Although some studies have been done, there are few accessions of tamarillo in germplasm banks and this makes the access to genetic variation in this species difficult for breeders. Many breeders have to rely on their own collections. Nonetheless, there is an important varia- tion in this species (Nuez et al., 1993) and a few accessions from the diversification area of this crop, the Andean region, can contain enough variation to begin a breeding program. The tamarillo is funda- mentally autogamous (Pringle and Murray, 1991), but there is some degree of heterogeneity among plants of a same accession, especially in traditional types. This variation appears either by spontaneous mutations or from introgression of genetic material from other popula- tions by accidental crossing with another genotype (Bohs, 1989a). This variation could be exploited for selection within heterogeneous accessions.

INTRASPECIFIC HYBRIDIZATION Crossing between different types of C. betacea is easy and there are no technical difficulties. Due to the autogamy of the tamarillo individ- uals have a high degree of homozygosis and therefore crossing among genetically different individuals gives homogeneous offspring. As each fruit can contain more than 300 seeds (Pringle and Murray, 1992b), the commercial production of the hybrid tamarillo seems fea- sible. However, there is a complete lack of information on the agro- nomic behavior of F1 hybrids. Most solanaceous horticultural crops are heterotic for yield characters (Kalloo, 1988), and this is probably echoed with the tamarillo. Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Obtaining segregant generations offers the opportunity for recom- bination and segregation, and therefore new superior genetic combina- tions can arise. However, there is a lack of studies giving information on the degree of variation in segregant generations. Despite requiring several years for evaluation, tamarillo can not be considered as a typical fruit crop, in which the period of evaluation can take as long as 20 years for an individual genotype. Nonetheless, 3 to 5 years are necessary for an evaluation of an individual and this makes it impracti- cal to use annual species breeding strategies, which may require 10 generations before release of an improved cultivar. Until studies are undertaken to obtain the corresponding value of the additive and dominant components of the genetic variance for each Jaime Prohens and Fernando Nuez 61

of the main interest characters, it will not be possible to know the most appropriate strategy for breeding this crop. Breeders desire develop- ment of pure lines or the development of F1 hybrids that maximize heterozygosis. Nonetheless, vegetative propagation offers the oppor- tunity to propagate the most valuable genotypes that may appear in segregant generations, like an F2 obtained from complementary or transgressive crossings. Cloning allows the conservation of the whole genotype, and can be of interest in the development of new cultivars. Micropropagation developed for tamarillo (Bargchi, 1998) allows for vegetative propagation while avoiding the transmission of viruses.

INTERSPECIFIC HYBRIDIZATION Interspecific hybridization could be useful for the transfer of char- acters of interest from certain wild species, mostly for disease and resistance, to the cultivated forms. Successful crossings have been achieved with C. acuminata Rusby and with C. uniloba Rusby. Morphologically, these species are quite similar to C. betacea. Tamarillo hybrids with C. acuminata have low fertility. However, those obtained with C. uniloba are vigorous and highly fertile (Bohs, 1991). Other Cyphomandra species such as C. hartwegii (Miers) Sendt. ex Walp. and C. sibundoyensis Bohs are also edible, and may have some potential in the future, on their own or as sources of genetic variation for tamarillo breeding (National Research Council, 1989).

POLYPLOIDY AND ANEUPLOIDY Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Either spontaneous tamarillo polyploids or those induced with col- chicine have low fertility and poor agronomic characteristics (Pringle and Murray, 1992b). However, some aneuploids with 25 chromo- somes, instead of 24 as the diploid types, show good fertility and give a similar or even higher yield and fruit size than their diploid counter- parts. Therefore, these aneuploids have good prospects for their use in commercial plantations (Pringle and Murray, 1992a, 1992b). Micropropagation Barghchi (1998) developed a protocol for micropropagation from axillary shoots, terminal buds and adventitious shoots and virus elimi- 62 SMALL FRUITS REVIEW

nation in the tamarillo. In vitro culture, combined with thermotherapy at 32-36_C resulted in the elimination of all viruses. Regenerated plants were symptomless and serological tests and electron microsco- py confirmed that the material was virus free.

Genetic Transformation

Agrobacterium mediated transformation of tamarillo has been suc- cessfully achieved and protocols for transformation are available (At- kinson and Gardner, 1993). Although food produced by transgenic plants is the subject of criticism in many sectors, the use of genetic transformation offers the opportunity for the improvement of many characters for which there is not enough genetic variation in the germ- plasm.

Breeding for Yield

Several evaluations of tamarillo germplasm have shown a high degree of genetic variation for yield and fruit weight. Differences among non-parthenocarpic materials can be as high as two-fold for fruit weight (Calabrese et al., 1995; Prohens et al., 1996b). Nonethe- less, there is also an important environmental component of these char- acters, and in all probability there is a high interaction of genotype  locality. Exploitation of this type of interaction situating in each local- ity the most adapted material could maximize the selection for yield. At present, the tamarillo is being introduced as a promising crop in a variety of environments, e.g., regions with a Mediterranean climate

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 (Calabrese et al., 1995; Prohens et al., 1997). A germplasm screening is essential when trying to introduce this crop in a new area. However, in order to select the most adapted types, most attempts to introduce tamarillo culture have been based on a single cultivar, and this has restricted the opportunity to exploit variation for local adaptation.

Breeding for Quality

Fruit quality is essential for consumer acceptance, but fruit shape is of interest because it affects fruit attractiveness and is important in terms of packaging and presentation. There are ample possibilities for selection in fruit shape as it can vary from round to elongated, with a Jaime Prohens and Fernando Nuez 63

ratio length/width higher than two among accessions. Round to oval shapes appear to be preferred. Fruit color varies from yellow types to purple and it may have stripes or not. Regarding characters related to organoleptic quality, differences among cultivars have been found for soluble solids, titratable acidity, and ascorbic acid and other characters (Romero-Rodríguez et al., 1994; Calabrese et al., 1995; Prohens et al., 1996b; Boyes and Strübi, 1997). High content is important in the processing industry. Cultivars with a higher sugar/acid ratio are probably more suited to the preferences of European and North American consumers (Williams, 1984). Prohens et al. (1996b) found 1 of 7 accessions with a lower level of titratable acidity (between 15 and 23%) and with similar levels of soluble solids resulting in a higher sugar/acid ratio, and a sweeter taste. Recently developed ‘Oratia Red’ and ‘Andys Sweet Red’ have a high sugar/acid ratio (National Research Council, 1989; Boyes and Strübi, 1997). However, breeding objectives should consider the mar- kets where the fruits are destined. In this way, for Japanese consumers, who are more used to acid fruits, it might be important to use cultivars in which the sugar/acid ratio is maintained at present values. Breeding for nutritive value in tamarillo also seems possible as genotype variation for ascorbic acid content and have been found (Morton, 1982; Rodríguez-Amaya et al., 1983; Romero-Rodríguez et al., 1994; Prohens et al., 1996b). Tamarillo has a relatively high content of vitamins A and C (Table 1). Levels of vitamin A are inter- mediate between those of tomato and carrot (Rodríguez-Amaya et al., 1983), while the ascorbic acid content is similar to that of citrus fruits.

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Aromatic compounds of tamarillo have been identified (Torrado et al., 1995; Wong and Wong, 1997) and selection of high aromatic culti- vars is of interest. However, aroma is a complex character, in which many interactions among different compounds are involved and in which environmental influence is considerable. Despite its potential importance, at present developing breeding plans aimed at improving this character seems to be deferred.

Breeding for Disease Resistance

Few studies have been devoted to tamarillo breeding for disease resistance. Most work has dealt with TaMV resistance. Resistance to 64 SMALL FRUITS REVIEW

TaMV is as yet unknown, even in wild species belonging to the genus Cyphomandra. Genetic transformation is being used to develop tama- rillo cultivars resistant to TaMV. Strategies used up to now have most- ly involved the use of genetic constructs which include sequences of the coat protein of this virus (Cohen et al., 1998). The use of mutagen- ic agents, such as nitrous acid for the production of defective TaMV strains, which could be used for cross-protection has not been success- ful (Eagles et al., 1994). Resistance to anthracnose is also being attempted by in vitro selec- tion of cells capable of growing in the presence of crude filtrate of the (Hoyos and Afanador, 1998). However, there are no reports of the efficacy of this strategy in developing mature plants resistant to this disease.

Breeding for Early Harvesting

Early harvesting is of interest as there are some differences among cultivars for earliness in fruit ripening (Calabrese et al., 1995). This could be exploited to select the earliest cultivars. There is also quanti- tative variation in the response to postharvest applications of ethylene in some cultivars so it is possible to achieve successful postharvest ripening (Prohens et al., 1996c). Despite being considered a non-cli- macteric fruit (Pratt and Reid, 1974), ethylene applications stimulate ripening (El-Zeftawi et al., 1988; Prohens et al., 1996a). In those materials in which ethylene induces ripening, fruit can be harvested at the turning stage and be ripened postharvest. This may allow storage of turning fruits, which may be ripened when needed. Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Breeding for Parthenocarpy

Plantations can be found with occasional trees that produce parthe- nocarpic (seedless) fruit. These trees come from spontaneous muta- tions and need to be vegetatively propagated. Parthenocarpic fruits are ovoid in shape and red to orange in color with green to coffee colored stripes. The flesh is orange in color. Fruit are smaller than other fruit and typically their weight is only around 20 g. Parthenocarpic tamaril- los would be very interesting due to their lack of seeds, however, low weight and low yield would need to be solved before this type of fruit can reach prominence. Jaime Prohens and Fernando Nuez 65

CONCLUSION

Tamarillo is a fruit crop with agronomic, organoleptic, physi- cochemical and nutritive properties that indicate that it may be both a well-adapted and profitable new crop in many frost-free areas around the world. Apart from its use for fresh consumption it has good pros- pects for the processed food industry. Plant breeding can contribute effectively to its expansion with the development of new cultivars that are more productive, consistent with consumer demands and that are more widely adapted to a variety of ecological and environmental production areas.

LITERATURE CITED

Atkinson, R.G., and R.C. Gardner. 1993. Regeneration of transgenic tamarillo plants. Plant Cell Rpt. 12:347-351. Azad-Thakur, N.S., Y.P. Sharma, and R.N. Barwal. 1988. Tree-tomato cultivation in Meghalaya. Indian Farming 37 (2):3. Barghchi, M. 1998. In vitro regeneration, plant improvement and virus elimination of tamarillo (Cyphomandra betacea (Cav.) Sendt.). In: Davey, M.R., Alderson, P.G., Lowe, K.C., Power, J.B. (Eds.). Tree biotechnology towards the millennium, pp. 173-185. Nottingham University Press; Nottingham, UK. Bilton, J. 1986. Tamarillo cook book. Irvine Holt, Auckland, New Zealand. Blank, R.H., M.H. Olson, and D.S. Bell. 1983. Screening insecticides to protect tamarillo against grass grub adults. Proc. 36th N.Z. Weed and Pest Control Conf.: 111-115. Blank, R.H., T.E. Dawson, and A.C. Richardson. 1991. A comparison of buprofezin and deltamethrin/oil for control of on tamarillo. Proc. 44th N.Z. Weed and Pest Control Conf.:237-241. Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Bohs, L. 1989a. Solanum allophyllum (Miers) Standl. and the generic delimitation of Cyphomandra and Solanum (). Ann. Missouri Bot 76:1129-1140. Bohs, L. 1989b. Ethnobotany of the genus Cyphomandra (Solanaceae). Econ. Bot. 43:143-163. Bohs, L. 1991. Crossing studies in Cyphomandra (Solanaceae) and their systematic and evolutionary significance. Amer. J. Bot. 78:1683-1693. Bohs, L. 1994. Cyphomandra (Solanaceae). The New York Botanical Garden, Bronx, New York. Boyes, S., and P. Strübi. 1997. Organic acid and sugar composition of three New Zealand grown tamarillo varieties (Solanum betaceum (Cav.)). N. Z. J. Crop Hort. Sci. 25:79-83. Brücher, H. 1977. Tropische nutzplanzen. Springer-Verlag, Berlin. Brücher, H. 1989. Useful plants of neotropical origin and their wild relatives. Spring- er-Verlag, Berlin. 66 SMALL FRUITS REVIEW

Carnevali, A. 1974. Il tamarillo: una nuova possibilità per la frutticoltura meridio- nale. Frutticoltura 36 (10/11):31-37. Cazar, E.A., F. Saavedra, and A. Ortega. 1989. Evaluación de cuatro sustratos para enraizamiento de esquejes de tomate de árbol. Rumipamba 6 (1):23-40. Calabrese, F., A. De Michele, F. Barone, I. Mirto, and M. Panno. 1995. Comporta- mento agronomico-qualitativo di cultivar di tamarillo in Sicilia. Rivista di Frutti- coltura 57 (7/8):43-46. Cohen, D., R. van der Brink, D. Beck, and R. Forster. 1998. Resistance to tamarillo mosaic potyvirus in transgenic tamarillos and expression of the transgenes in F1 progeny. Abstracts of the XXV International Horticultural Congress, Brussels 2-7 August 1998:160. Cooper, K.M., and G.S. Grandison. 1987. Effects of vesicular-arbuscular mycorrhi- zal fungi on infection of tamarillo (Cyphomandra betacea)byMeloidogyne incognita in fumigated soil. Plant Dis. 71:1101-1106. de Vincenzi, M., P. Maialetti, and M.R. Dessi. 1995. Monographs on botanical flavouring substances used in foods. Part IV. Fitoterapia 66:203-210. Duke, J.A. and J.L. duCellier. 1993. Handbook of alternative cash crops. CRC Press, Boca Raton, FL. Eagles, R.M., R.C. Gardner, and R.L.S. Forster. 1994. Incidence and distribution of six viruses infecting tamarillo (Cyphomandra betacea) in New Zealand. N. Z. J. Crop Hort. Sci. 22:453-458. El-Zeftawi, B.M., L. Brohier, L. Dooley, F.H. Goubran, R. Holmes, and B. Scott. 1988. Some maturity indices for tamarillo and pepino fruits. J. Hort. Sci. 63 (1):163-169. Fischer, G., and P. Ludders. 1994. Die Baumtomate (Cyphomandra betaceae)--eine alte Obstart des tropischen Hochlandes mit neuen Perspektiven. Erwebsobstbau 36 (3):74-78. Fletcher, J.D. 1987. New plant disease records in New Zealand: additional hosts of alfalfa mosaic virus and cucumber mosaic virus. N. Z. J. Agric. Res. 30:505-506. Grau, A. 1994. Aptitud climática del noroeste argentino para el cultivo de frutales tropicales y subtropicales: Un análisis comparativo con otras áreas subtropicales

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 del mundo. Revista Industrial y Agrícola de Tucumán 71:31-39. Gupta, D.K., and K.C.B. Choudhary. 1994. New leaf spot of tree tomato caused by Alternaria alternata. Indian J. Mycol. and Plant Pathol. 24:238. Heatherbell, D.A., M.S. Reid, and R.E. Wrolstad. 1982. The tamarillo: chemical composition during growth and maturation. N. Z. J. Sci. 25:239-243. Heiser, C.B. 1969. Nightshades, the paradoxical plants. W.H. Freeman, San Francisco. Hewett, E.W. 1993. New horticultural crops in New Zealand. In: Janick, J., Simon, J.E. (Eds.). ‘‘New crops,’’ pp. 57-64. John Wiley and Sons, New York. Hoyos, R.A., Afanador, L. 1998. Sistemas biotecnológicos para la selección acelera- da del tomate de árbol (Solanum betaceum) por su resistencia a la antracnosis. 2nd Seminario Frutales de Clima Templado, Manizales, 12-14 August 1998, pp. 40-46. Kalloo, G. 1988. Vegetable breeding. Volume I. CRC Press, Boca Raton, Florida. Morton, J.F. 1982. The tree tomato, or ‘‘tamarillo,’’ a fast-growing, early-fruiting small tree for subtropical climates. Proc. Fla. State Hort. Soc. 95:81-85. Jaime Prohens and Fernando Nuez 67

Muggleston, S. 1994. Feijoa and tamarillo cultivars developed by HortResearch. The Orchadist 67 (7):47-49. National Research Council. 1989. Lost crops of the Incas: little-known plants of the Andes with promise for worldwide cultivation. National Academy Press, Wash., D.C. Nuez, F., Morales, R., Ruiz, J.J., Fernández de Córdova, P., Valdivieso, E., González, F.I. 1993. Recolección de especies hortícolas en Ecuador. Plant Gen. Res. Newsl. 96:29-33. Nuez, F., Morales, R., Prohens, J., Fernández de Córdova, P., Soler, S., Valdivieso, E., Solórzano, V. 1999. Germplasm of Solanaceae horticultural crops in the south of Ecuador. Plant Gen. Res. Newsl.: in press. Osorio, G. 1992. Avances en el cultivo del tomate de árbol (Cyphomandra betacea). Acta Hort. 310:199-205. Pileri, A.M. 1989. Il tamarillo. Rivista di Frutticoltura 51 (11):67-70. Pliansinchai, U., and D.S. Teakle. 1994. Susceptibility of tamarillo to seven plant viruses. Australasian Plant Pathol. 23:25-28. Pratt, H.K., and M.S. Reid. 1976. The tamarillo: fruit growth and maturation, ripen- ing, respiration, and the role of ethylene. J. Sci. Food Agric. 27:399-404. Pringle, G.J., and B.G. Murray. 1991. Reproductive biology of the tamarillo, Cypho- mandra betacea (Cav.) Sendt. (Solanaceae), and some wild relatives. N. Z. J. Crop Hort. Sci. 19:263-273. Pringle G.J., and B.G. Murray. 1992a. Polyploidy and aneuploidy in the tamarillo, Cyphomandra betacea (Cav.) Sendt. (Solanaceae) I. Spontaneous polyploidy and features of the euploids. Plant Breeding 108:132-138. Pringle G.J., and B.G. Murray. 1992b. Polyploidy and aneuploidy in the tamarillo, Cyphomandra betacea (Cav.) Sendt. (Solanaceae) II. Induction of tetraploidy, interploidy crosses and aneuploidy. Plant Breeding 108:139-148. Proctor, F.J. 1990. The European Community market for tropical fruit and factors limiting growth. Acta Hort. 269:29-39. Prohens, J., J.J. Ruiz, and F. Nuez. 1996a. Advancing the tamarillo harvest by induced postharvest ripening. HortScience 31:109-111.

Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 Prohens, J., J.J. Ruiz, and F. Nuez. 1996b. El tomate de árbol (Cyphomandra beta- cea): Un nuevo cultivo para el área mediterránea. Información Técnica Económi- ca Agraria Vol. Extra 17:185-194. Prohens, J., J.J. Ruiz, and F. Nuez. 1996c. Variabilidad en el comportamiento en postcosecha del tomate de árbol. In: Chamarro, J., and J. Pozueta (Eds.). IV Simposio Nacional, I Ibérico sobre maduración y post-recolección de frutos y hortalizas, Servicio de Publicaciones de la Universidad Politécnica de Valencia, Valencia, Spain, pp. 151-154. Prohens, J., J.J. Ruiz, and F. Nuez. 1997. El tomate de árbol, un cultivo prometedor para regiones de clima mediterráneo. Agrícola Vergel 14:209-214. Rathore, D.S. 1992. Physico-chemical evaluation of tree-tomato fruits. Progressive Hort. 24:233-234. Richardson, A., and T. Dawson. 1994. Tamarillo nutrition. Orchadist of New Zea- land. 67:50-53. 68 SMALL FRUITS REVIEW

Richardson, A., and K. Patterson. 1993. Tamarillo growth and management. The Orchadist 66 (12):33-35. Rodríguez-Amaya, D.B., P.A. Bobbio, and F.O. Bobbio. 1983. Carotenoid composi- tion and vitamin A value of the Brasilian fruit Cyphomandra betacea. Food Chem. 12:61-65. Romero-Rodriguez, M.A., M.L. Vazquez-Ochoa, J. Lopez-Hernandez, and J. Simal- Lozano. 1994. Composition of babaco, feijoa, passion-fruit and tamarillo pro- duced in Galicia (NW Spain). Food Chem. 49:251-255. Rotundo, A., C. Raffone, and S. Rotundo. 1981. Una prova di coltura del tamarillo in Campania. Frutticoltura 43 (6):41-46. Saldarriaga, A., J.A. Bernal, and P.J. Tamayo. 1997. Enfermedades del cultivo del tomate de árbol en Antioquia: Guía de reconocimiento y control. Corpoica, Río Negro, Antioquia, . Sale, P.R. 1983a. Tamarillos: management. New Zealand Ministry of Agri- culture and Fisheries Aglink HPP 297, 4 p. Sale, P.R. 1983b. Tamarillos: pests and diseases. New Zealand Ministry of Agricul- ture and Fisheries Aglink HPP 298, 4 p. Sánchez-Vega, I. 1992. Frutales and inos: Tomate de árbol (Cyphomandra betacea). In: Hernández-Bermejo, J.E., León, J. (Eds.). ‘‘Cultivos marginados: otra per- spectiva de 1992,’’ pp. 183-186. FAO, Rome, Italy. Shaw, J.M.H. 1996. Tree tomatoes cultivated in Britain. New Plantsman 3:67-74. Symon, D.E. 1985. The Solanaceae of New Guinea. J. Adelaide Bot. Gard. 8:1-171. Teakle, D.S., M.E. Yarker, and I.F. Muirhead. 1986. Tamarillo fungal diseases at Mt. Glorious, Queensland. Australian Plant Pathol. 15 (3):68-69. Torrado, A., M. Suárez, C. Duque, D. Krajewski, W. Naugebauer, and P. Schreier. 1995. Volatile constituents from tamarillo (Cyphomandra betacea Sendtn.) fruit. Flavour and Fragrance J. 10:349-354. Towle, M.A. 1961. The ethnobotany of pre-Columbian . Aldine, Chicago. Velastegui, J.R., and S.F.L. Ball. 1991. First record of Sclerotinia sclerotiorum on tree tomato in Ecuador. Plant Pathol. 40:476-477. Velastegui, J.R., and B.E. Fiallos. 1987. Plant parasitic nematode problems in some horticultural crops in Ecuador. Int. Nematology Network Newsl. 4:3-5. Williams, P. 1984. Sweeter tamarillo needed for overseas markets. Growing Today 2 Downloaded by [Pontificia Universidad Javeria] at 15:15 29 May 2013 (2):18-19. Wong, K.C., and S.N. Wong. 1997. Volatile constituents of Cyphomandra betacea Sendtn. fruit. J. Essential Oil Res. 9:357-359. Yearsley, C.W., B.Y. Huang, H.J.W. McGrath, J. Fry, M.G.H. Stec, and J.R. Dale. 1988. Red tamarillos (Cyphomandra betacea): comparison of two postharvest strategies for the control of fungal storage disorders. N. Z. J. Exp. Agric. 16:359-366.