Oil Palm: Plant Breeding

Oil Palm Genetic Improvement

Germplasm Resources
Improvement Objectives
Breeding Techniques
Future Prospects


A. Origins

The African oil palm (Elaeis guineensis Jacq.), which is the oil palm of commerce, is endemic to tropical Africa stretching from the Atlantic coast (Guinea) in the west to Zanzibar and the island of Madagascar in the east and from the sub-Sahara in the north (Senegal, 16 °N) to the south of Angola (15 °S) bordering Namibia (Hartley 1988; Latiff 2000). The center of origin and diversity appears to be concentrated in the tropical rain forests of west and central Africa (Angola, Cameroon, Congo, Ghana, Ivory Coast, Nigeria and Zaire). They occur naturally as semi-wild groves in swamps and riverine forest fringe areas in the plains usually close to settlements but are also found on drier and higher grounds up to the altitude of 1500 m above sea level. The American oil palm (Elaeis oleifera) which also produces an oil in smaller quantities consumed by the natives and is of interest in breeding because of some of its desirable attributes, however, is endemic to tropical Latin America stretching from Mexico in the north to the Amazonas of Bolivia, Brazil, Colombia and Peru in the south and straddling the Pacific and Atlantic coasts. They also occur naturally in groves in open grasslands and riverine areas and their distribution appears to be associated with indigenous Indian migratory movements (Santos et al. 1986). The distribution of the groves tended to be more discontinuous.

The genus Elaeis, which belongs to the Cocoideae subfamily of the Palmaceae, has an American or African center of origin. The two oil palm species were presumed to have diverged when the American and African continents drifted apart in prehistoric times (Zeven 1965). There are two lesser-known species of Elaeis: E. odora (South America) and E. madascariensis (Africa).

B. Crop status

Crude palm oil extracted traditionally from the fruit pulp of the semi-wild oil palms was the source of dietary fat and certain vitamins (A and E) of the indigenous populations of tropical Africa and America. Interest in the oil palm as a crop arose as a substitute for animal fat in the manufacture of soap, candle wax and margarine. Plantations were started in the East Indies (Indonesia, Malaysia) by the European colonists to ensure a steady supply of the raw material (Hartley 1988). Two seedlings each from the botanic gardens of Amsterdam and Mauritius, the thick-shelled or dura form (Plate 1A) derived presumably from the same palm in West Africa, were taken and grown in the Bogor Botanic Gardens, Java, Indonesia in 1848. With the expanding interest in the crop, subsequent hybridizations and selections were made from these four Bogor palms and the progenies distributed to the Deli province in Sumatra and thence Malaysia (Malaya then) to become known as the Deli dura population (Rosenquist 1986). This uniform high oil yielding Deli dura was the commercial planting material for the rapidly expanding plantations in the Far East from 1911 till the early 1960s. With the revelation of monogenic inheritance of the shell gene by Beirnaert and Vanderweyen (1941) and that the hybrid progenies of the thick-shelled dura and the shell-less female sterile pisifera are 100% thin-shelled teneras having thick-mesocarp and thence higher oil yield (Plate 1A), the change to the tenera hybrid planting material was very rapid as teneras from West Africa had been imported and bred earlier by researchers in the Far East and they became the source of the pisiferas (Hartley 1988).

Plate I. A) Thick shelled dura (D), shell-less pisifera (P), and thin shelled hybrid tenera (T) fruits of oil palm

The oil palm is the second most important oil crop next to soybean and is poised to become the dominant oil crop early in the new decade (Mielke 2000; Yusof and Mohd Arif 2000). Palm oil constitutes 19% of the world’s oils and fats production and is the dominant oil of international trade. The oil is produced from about 6 million hectares of plantations in the countries of the humid tropics i.e. Colombia, Indonesia, Ivory Coast, Malaysia, Nigeria, Thailand, with Malaysia accounting for 48% and Indonesia 31% of production. With the rapid expansion of the world population particularly in the third world countries where dietary fat intake is still very low, per capita oil and fat consumption is likely to increase tremendously and the oil palm being the most productive and profitable oil crop will continue to expand in its cultivation to meet this demand.

C. Uses

The oil palm fruit bunch produces two types of oil, “palm oil” from the mesocarp (20%) and “palm kernel oil” from the kernel (3%). Crude palm oil extracted from the sterilized mesocarp is refined, bleached from its original orange-red color, and deodorized to give refined palm oil used solely or blended with other oils in cooking oil, salad oil, margarines and spreads. The refined oil is fractionated to give olein and stearin and with further fractionation gives fatty acids and alcohols, intermediate commodities traded and used in food and oleochemical industries. Palm oil can be used as a biofuel as with other vegetable oils. About 80% of palm oil, however, is used in the food industries although its other uses are increasing. Palm kernel oil is a competitor for coconut oil and has more uses in the oleochemical industries. Fig.1 is a summary chart of the fractionated products and their uses.

Enlarge Fig. 1: Uses of palm oil

Secondary and waste products from the palm oil industry are assuming economic importance prompted largely by health and environmental concerns. Carotene from the crude palm oil can be processed into Vitamin A supplement and a natural dye for snack foods e.g. instant noodles. Likewise, tocopherols and tocotrienols can be extracted from palm oil for industrial Vitamin E production (Choo 2000; Jalani et al. 1997). Kernel cake and sludge cake, wastes from the palm and kernel oil extraction processes, respectively have use as animal feed while the fruit bunch stalk fiber waste can be used directly in the plantation as an organic mulch or processed into an organic compost.

Soh, A.C., Wong, G., Hor, T.Y., Tan, C.C. and Chew, P.S. 2003. Oil palm genetic improvement. In: Janick, J. (ed.). Plant Breeding Reviews Vol. 22. John Wiley & Sons, New Jersey, pp. 165-219

Note: The full list of references quoted in this article is available from the above paper.