Pithecellobium dulce (PROSEA)
Pithecellobium dulce (Roxb.) Benth.
- Protologue: London Journ. Bot. 3: 213 (1844).
- Family: Leguminosae
- Chromosome number: 2n= 26
- Mimosa dulcis Roxb. (1798),
- Inga dulcis (Roxb.) Willd. (1806).
The genus name is often written as Pithecollobium or Pithecolobium .
- Guayamochil, Manila tamarind, sweet inga (En)
- Indonesia: asam Belanda, asem londo (Java), asam koranji (Sunda)
- Malaysia: asam kranji, asam tjina
- Philippines: kamatsile (Tagalog), kamanchilis (Bisaya), damortis (Ilokano)
- Burma: kway-tanyeng
- Cambodia: âm'pül tük
- Laos: khaam th'ééd
- Thailand: makham-thet (central), makham-khong (Phrae)
- Vietnam: me keo, keo tây.
Origin and geographic distribution
P. dulce originates from Central America. It has been naturalized throughout the tropics. It was introduced in Indonesia by the Portuguese traders and in the Philippines by the Spaniards; it is also common in Malaysia and Thailand.
The aril of P. dulce is eaten fresh; it can be astringent but in selected clones in the Philippines it is sweet and rather dry and mealy. The seed oil is also edible, while the seed meal may be used as an animal feed. The leaves when applied as a plaster can allay pain of venereal sores and relieve convulsions and taken with salt can cure indigestion, but can also produce abortion. The root bark may be used to cure dysentery. Tannin - used to soften leather - can be extracted from the bark, seeds and leaves; the bark is also used to dye fish nets. P. dulce is a common roadside tree, in Indonesia particularly in towns, where it is pruned into a shapely avenue tree. It is also a good hedging plant, although not fully goat-proof: the young shoots serve as fodder. Frequent clipping precludes flowering and fruiting of avenue trees and hedges. A variegated mutant is used as an ornamental pot plant.
Production and international trade
In the Philippines the fruit is sold in local markets but much of the crop is consumed at home.
The fresh pod consists of 25% peel, 50% aril and 25% seed. The aril contains per 100 g: water 75.8-77.8 g, protein 2.3-3 g, fat 0.4-0.5 g, carbohydrates 18.2-19.6 g, fibre 1.1-1.2 g, ash 0.6-0.7 g, calcium 13 mg, phosphorus 42 mg, iron 0.5 mg, sodium 19 mg, potassium 20.2 mg, vitamin A 25 IU, thiamine 0.24 mg, riboflavin 0.1 mg, niacin 0.6 mg and vitamin C 133 mg. The energy value is 330 kJ/100 g.
- Shrub or small tree, up to 10 m tall, with glabrescent round branchlets, armed with straight, paired, stipular spines, 4-10 mm long.
- Leaves abruptly bipinnate with a single pair of pinnae only; rachis 1-2.5 cm long; pinnae with rachis up to 7.5 mm long with small terminal stipular spines; leaflets two per pinna, opposite, sessile, ovate-asymmetrical, 1.5-3.5 cm × 1-2 cm, glabrous.
- Inflorescences in terminal panicles, puberulent, up to 10 cm long; peduncles 1-2 cm long, bearing globular heads with 15-20 sessile whitish flowers; calyx and corolla tubular, 1.5 mm and 3.5 mm long respectively; filaments white.
- Fruit (pod) flattened, linear-oblong but curled up, 1 cm wide, fleshy coriaceous, reddish-brown.
- Seeds flattened, obovate-asymmetrical, 9 mm × 7 mm × 2 mm, blackish, with a thick, spongy, rather dry aril.
Seedling trees take 5-8 years to start bearing fruits. In the Philippines they flower from October to November and bear mature fruits in abundance during January and February; in West Java bloom is between April and June and the pods ripen 2-3 months later, from June to August.
P. dulce is not exacting in its climatic requirements and grows well at low and medium altitudes in both wet and dry areas under full sunlight. Although well-drained soil is best, it also grows successfully in heavy clay soils.
P. dulce is usually propagated from seeds, which take about 2 weeks to germinate. Outstanding trees however should be propagated vegetatively by marcotting, grafting or budding. Once planted in the field the tree does not receive any treatment other than occasional pruning. Pests and diseases do not seem to present serious problems.
The pods are usually picked by climbing the tree or using a long bamboo pole. When mature, the fruits split open at the lower suture exposing the aril. For this reason the fruit does not keep long and has to be eaten within a few days.
Genetic resources and breeding
As far as it is known selection of outstanding trees is being done only in the Philippines. The objective is to select trees that produce large pods containing small seeds covered by red arils.
In South-East Asia P. dulce is mainly grown as a hardy, easy-to-manage roadside tree. These properties also make it a valuable hedging plant, but it is not much utilized for that purpose in the region. Only in the Philippines is the tree grown primarily for the pods and it is unlikely that this situation will change.
- Anonymous, 1989. Asam Kranji dan Asam Londo [Dialium indum and Pithecellobium dulce]. Majalah ASRI No 26.
- Azis Lahiya, A., 1985. Budidaya tanaman hortikultura, buah-buahan di Indonesia [Cultivation of horticultural plants, fruits of Indonesia]. Jilid II. Bandung.
- Gonzalez, E.V., Manas, A.E., Muli, E.I., Filamor, J.R., Maza, C.C. & Marero, R., 1974. Tannin-extract production from local (Philippine) materials; their utilization for tanning hides and skins. Forpride Digest 3(3/4): 10-22.
- Nielsen, I., 1981. Flore du Cambodge, du Laos et du Vietnam. Vol. 19. Légumineuses-Mimosoïdées. Muséum National d'Histoire Naturelle, Laboratoire de Phanérogamie, Paris. pp. 108-110.
H. Hendro Sunarjono & R.E. Coronel