Topee tambo (Calathea allouia), Allouya.
Botanical name
Calathea allouia (Aubl.) Lindl. Also referred to as Allouya americana (Lamk.).
Family
Marantaceae.
Other names
Agua bendita (Venez.); All�luia (Fr.); Ari� (S. Am.); Cocurito (Venez.); Curcuma d'Amerique (Fr.); Guinea arrowroot (Carib.); Kopffomige marante (Ger.); L�iren, Leren (S. Am.); L(l)erenes (P. Rico); Sweet corn root (Carib.); Topinambour (blanco) (Ant.); Topitambo/u (W.I.); Touple nambours (St. Lucia); Tumpinambou, Uari� (S. Am.).
Botany
The plant is a herbaceous perennial, with a fleshy rootstock bearing erect or almost erect leaves with long, grooved petioles and elongated, oval blades reaching to a height of 0.5-1 m. In old plants there is a pseudostem, consisting of a short stalk, 10-30 cm long, bearing a few greenish to yellow or white flowers which rarely set seeds. At the base of the plant are fibrous roots, some of which produce clusters of ovoid tubers in the upper soil surface.
Origin and distribution
Evidence is scant, but the plant is generally believed to be native to northern South America, some of the lesser Antilles, Hispaniola and Puerto Rico: it has been introduced to Madagascar, India, Sri Lanka, Malaysia, Indonesia and the Philippines.
Cultivation conditions
Topee tambo is adapted to a tropical climate of alternating wet and dry seasons, with the dry season occurring during the short day season of the tropical winter. A moderate annual rainfall of 150-200 cm is required. Planting is shortly before the start of the rainy season.
Soil-ideally a loose loam or clay that permits good drainage. The addition of FYM or other organic manure is particularly beneficial. Neither very heavy clays nor sandy soils are suitable.
Planting procedure
Material-the seed material usually consists of 'suckers', short sections of the rhizome with an upright terminal bud, which are obtained by breaking up the clump of rhizomes forming the basal portion of an old plant. After harvest the rhizomes are normally stored in a cool, dry place until required for planting, and they are not divided until that time. Germination is often erratic, but it has been shown that immersing the suckers in water at 48°C for 10 minutes gave over 90 per cent sprouting. Under some conditions the rhizomes may be left in the ground until the approach of the planting season: however, intense shoot competition arising under such conditions leads to depressed yields unless they are separated. The yield from a single replanted offshoot is often greater than that of a whole clump, with very much larger individual tubers.
Method-preparation of the soil should take into account its water relations. Where regular, heavy rainfall is expected planting should be on ridges, with moderate rainfall planting on the flat is satisfactory, but if rainfall is likely to be limited and the soil has poor water-holding capacity planting should be in small pits to which organic matter has been added. Weeding in the early stages of growth is important.
Field spacing-recommended distances are about 40 cm between plants on ridges 80-100 cm apart (25 000-31 000 plants/ha) or on the flat 40-80 cm apart (16 000-62 000 plants/ha).
Pests and diseases
The insect Calopodes ethlius is reported to attack the tubers. Fungal or bacterial rotting of rhizomes that suffer excessive flooding may occur. The foliage appears to suffer little from pests or diseases.
Growth period
A crop of tubers is produced 9-12 months after planting.
Harvesting
The small tubers are usually dug up by hand with a fork.
Primary product
Tuberous roots-which resemble small potatoes. They are ovoid, usually 3.5-6 cm long with a diameter of 2.5-3.5 cm, and covered with a thin parchment-like skin and yellowish-gray in colour.
Yield
Yields of 2-12 t/ha have been reported. Low yields have been associated with drought towards the end of the (normally) wet season. Irrigation would be necessary in such circumstances.
Main use
The tuberous roots are free of fibre and are normally eaten boiled. After 15 minutes boiling the initial raw flavour disappears and the product is crisp in texture and said to have a unique flavour, somewhat resembling sweet corn, though with a slightly bitter but not unpleasant aftertaste. The unusual texture and flavour have been described as making these tubers 'a gourmet item that should compete with popular hors d'oeuvres'. Longer cooking, up to 60 minutes, makes the texture more floury, like that of potato.
Secondary and waste products
A tincture of the leaves is reported to be used in traditional South American medicine for the treatment of cystitis and as a diuretic.
Special features
An analysis of the edible portion of the tubers has been published as: energy 395 kJ/100 g; water 75.7 per cent; protein 1.5 per cent; fat 0.3 per cent; carbohydrate 21.4 per cent. About 70 per cent of the carbohydrate is starch. A carbohydrate similar to laevulose is present. The tubers are reported to be rather mucilaginous.
Major influences
Although Calathea allouia is currently a crop of only minor importance, said to be partly due to its intolerance of both drought and waterlogging, recent reports from Puerto Rico emphasise its possibilities as a specialist food. In the Amazon region of Brazil it is being collected for germplasm as a potentially important basic food, similar to potatoes but more suited to Amazon conditions.
Bibliography
ANON. 1892. Allouya tubers. Royal Botanic Gardens, Kew, Bulletin of Miscellaneous Information, (70), 244-245.
BUENO, C. R. and WEIGEL, P. 1981. Brotacao e desenvolvimento inicial de rizomas de ari� (Calathea allouia (Aubl.) Lindl.) [Sprouting and initial development of the rhizomes of the ari�.] Acta Amazonica, II, 407-410.
CHEVALIER, Aug. 1936. Le topinambour des Antilles et de la Guyane. Allouya americana (Lamk.) A. Chev. Revue de Botanique Appliqu�e et d'Agriculture Tropicale, 16, 973-981.
COBLEY, L. S. 1956. Topee tamboo, leren. An introduction to the botany of tropical crops, pp. 187-188. London: Longmans, Green and Co. Ltd, 357 pp.
L�ON, J. 1977. Origin, evolution and early dispersal of root and tuber crops. Proceedings of the 4th Symposium of the International Society for Tropical Root Crops (Colombia, 1976), IDRC-080e (Cock, J., Maclntyre, R. and Graham, M., eds), pp. 20-36. Ottawa, Canada: International Development Research Centre, 277 pp.
MACMILLAN, H. F. 1962. Root or tuberous vegetables and food crops. Tropical planting and gardening, 5th edn, p. 287. London: Macmillan and Co. Ltd, 560 pp.
MARTIN, F. W. and CABANILLAS, E. 1976. Leren (Calathea allouia), a little known tuberous root crop of the Caribbean. Economic Botany, 30, 249-256.
MONTALDO, A. 1972. Lairen. Cultivo de ra�ces y tub�rculos tropicales, pp. 229-230. Lima, Peru: Instituto Interamericano de Ciencias Agricolas de la OEA, 284 pp.
