Articles

Cocos nucifera L.

Cocos nucifera L.

Family

Palmae

Synonyms

Cocos nana Griff.

Vernacular Names

Malaysia

Kelapa.

English

Coconut (Palm and fruit).

Indonesia

Kelapa (General), nyiur (Malay), krambil (Ja­vanese).      

Papua New Guinea

Kokonas.

Philippines

Niyog (Pilipino, Tagalog), in­-iug (Ibanag), lubi, ungut (Bisaya), laying (Mano­bo).

Myanmar

Ong.

Cambodia

Doong.

Laos

Phaawz.

Thailand

Ma phrao (General), kho­saa (Karen-Mae Hong Son), dung (Chong-Chan-­thaburi).

Vietnam

D[uwf]a.

French

Cocotier (palm), coco (fruit).

Geographical Distributions

Cocos nu­cifera is native to the coastal regions of tropical Asia and the Pacific, but its primary centre of ori­gin is the subject of speculation. Fossil of Cocos nu­cifera has been found as far apart as India and New Zealand. The ability of the thickly husked and slow-germinating fruit of wild coconut (called Niu Kafa type) to remain viable after floating long dis­tances at sea ensured wide natural dispersal in the Indo-Pacific long before domestication may have started in Malaysia. The domesticated co­conut (called Niu Vai type) has a robust stem and large fruits, which however cannot survive long periods of floating at sea because of thinner husks and shells and quicker germination. Initial dis­semination of the domesticated Cocos nu­cifera coincided with migrations of Malay people to the Pacific and India, which started some 3000 years ago. Where wild coconut already occurred, there was opportunity for introgression with domesticated types, as both retained full cross compatibility. Polynesian, Malay and Arab navigators played an important role in further dispersal of Cocos nu­cifera into the Pacific, Asia and East Africa. Cocos nu­cifera be­came truly pantropical in the 16th Century after European explorers had taken it to West Africa, the Caribbean and the Atlantic coast of tropical America.

Description

Cocos nu­cifera is an unarmed, unbranched, pleo­nanthic, monoecious palm tree and with a terminal crown of leaves. It can grow up to 20-30 m in tall cultivars and 10-15 m in dwarf cultivars. The roots are mostly 1.5 m in the top layer of soil, normally measuring 6 m x 1 cm and up to 30 m long in opti­mum soil conditions. Its stem is cylin­drical, erect, often curved or slanting, measures 20-40 cm in diametre, but the swollen base ('bole') is up to 60 cm. It is light grey, becomes bare and conspicuously ringed with scars of fallen leaves.

The leaves are sheath­ing, spirally arranged, pinnate, measure 4.5-6(-7) m long, and up to 60-70 per plant of which one half is still un­folded in the central spear. The petiole is stout with clasping, fibrous sheath at the base, about one quar­ter of total leaf length, grooved above and rounded be­neath. There are 200-250 leaflets which are linear-lance-shaped, and measuring 50-120 cm x 1.5-5 cm. They are single folded lengthwise at base, with acute apex and regularly arranged in one plane.

The inflo­rescence is an axillary, protandrous, unopened (imma­ture) raceme which looks like a spadix within a spathe. It is opened (mature) about 1-2 m long, consists of a central axis with up to 40 lateral, spirally arranged, spike-like rachillae (branches), of which each bears 200­-300 male flowers and with only one to few female flow­ers near the bare basal part. The male flowers are 1-3 to­gether, sessile, measuring 0.7-1.3 cm x 0.5-0.7 cm, pale yellow, with 3 small sepals, 3 larger petals, 6 sta­mens in 2 whorls and a rudimentary pistil. The female flowers are solitary, much larger than male flowers, spherical in bud, ovoid at anthesis, measure 2-3 cm in diame­tre, enveloped by 2 small scaly bracteoles, 3 sepals and 3 petals, suborbicular, sub-equal, persis­tent and enlarged in fruit. The pistil is with large 3-loc­ular ovary, 3 sessile triangular stigmas and 3 nec­taries near the ovary base.

The fruit is a spherical, ovoid or el­lipsoidal fibrous drupe. It is indistinctly 3-angled, measures 20-30 cm long and weighs up to 2.5 kg. The exocarp is very thin, measures 0.1 mm thick, smooth, green, brilliant or­ange, yellow to ivory-coloured when ripens and usually drying to grey-brown in old fruits. The mesocarp is fi­brous, measures 4-8 cm thick and pale brown. The endocarp (shell, together with its contents are called the 'nut' of com­merce) is ovoid, measures 10-15 cm in diametre, 3-6 mm thick, hard, stony, dark brown, indistinctly 3-an­gled with 3 longitudinal ridges and 3 large, slight­ly sunken pores ('eyes') at basal end and each with an operculum.

There is only 1 large seed with a thin brown testa that is closely appressed to endocarp and ad­hering firmly to endosperm ('meat'), which is firm, measures 1-2 cm thick, white and oily. At the basal end in en­dosperm, a small peglike embryo 0.5-1 cm long is embedded (under one of the endocarp pores). In the centre of seed, there is a large central cavity, partially filled with coconut water, which is completely ab­sorbed 6 months after harvesting.

Ecology / Cultivation

Cocos nu­cifera is essentially a crop of the humid tropics. It is fairly adaptable to temperature and water supply. Hence, it is highly valued as still being common near the lim­its of its ecological zone. The annual sunlight re­quirement is above 2000 hours, with a likely lower limit of 120 hours per month. The optimum mean annual temperature is estimated at 27°C with av­erage diurnal variation of 5-7°C. For good yield, a minimum monthly mean temperature of 20°C is required. Temperatures below 7°C may seriously damage young palms, but cultivars differ in their tolerance of low temperature. While most Cocos nu­cifera is planted in areas below 500 m, it may thrive at altitudes up to 1000 m, although low temperatures will affect growth and yield. Generally, palms grow in areas with evenly dis­tributed annual rainfall of 1000-2000 mm and high relative humidity, but they can still survive in drier regions if there is adequate soil moisture. The semi-xerophytic leaves enable Cocos nu­cifera to minimize water loss and withstand drought for several months. In India, a monthly rainfall of 150 mm (with only a 3-month dry peri­od) is enough, while in the Philippines, rainfall of 125-195 mm (1500-2300 mm annually) is ideal. Cocos nu­cifera thrives in a wide range of soils, from coarse sand to clay, if soils have ade­quate drainage and aeration. Cocos nu­cifera is halophytic and tolerates salt in the soil well. Cocos nu­cifera can grow in soils with a wide range of pH but grows best at pH 5.5-7.

Line Drawing / Photograph

BOT00380

References

  1. Plant Resources of South-East Asia No.14: Vegetable oils and fats.