oil palm bulletin 50 (may 2005) p. 1-13 oil palm...

Oil Palm – Achievements and Potential

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Oil Palm – Achievements and Potential+

Mohd Basri Wahid*; Siti Nor Akmar Abdullah** and Henson, I E*

Oil Palm Bulletin 50 (May 2005) p. 1-13

ABSTRACT

Cultivation of the oil palm (Elaeis guineensisJacq.) has expanded tremendously in recentyears such that it is now second only tosoyabean as a major source of the world supplyof oils and fats. Presently, Southeast Asia is thedominant region of production with Malaysiabeing the leading producer and exporter of palmoil. This article reviews the various factorsthat have led to oil palm occupying itspresent position, including biological, technical,managerial, environmental and socio-politicalaspects.

Biological features recognized as criticalto the high productivity of the crop areexamined. These include its perennial andevergreen nature (giving a continuous year-round canopy cover intercepting a highproportion of incoming radiation), the year-round production of fruit bunches and the highpartition of total assimilates into harvestedproduct.

Scientific and managerial aspectscontributing to the success of the crop includethe significant genetic improvements andproduction of high quality planting materials,the development and application of finely-tunedagronomic practices, the appropriate scale andefficient organization of oil palm plantationsand the continuous R&D and good infra-structural support provided in the mainproducing countries.

The programmes of crop improvementthrough the utilization of traditional breedingand selection methods, the development andbenefits of vegetative propagation techniquesusing tissue culture and ongoing efforts to applymolecular and genetic engineering techniques to

* Malaysian Palm Oil Board, P. O. Box 10620, 50720 Kuala Lumpur, Malaysia.

** Department of Agricultural Technology, Faculty of Agriculture,Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.

This paper was first presented at the International Crop Science Congress and is published in the 2004 Special Issue of the PlantProduction Science, Proceedings of the Fifth Asian Science Conference held in Brisbane, Australia and organized by Australia Societyof Agronomy in collaboration with International Crop Science Society of USA from 26 September to 1 October 2004.

improve and modify oil composition, arereviewed.

Finally, the nutritional qualities of palmoil as a healthy component of diet are brieflydescribed.

ABSTRAK

Penanaman sawit (Elaeis guineensis Jacq.)telah berkembang dengan pesatnya padakebelakangan ini dan kini menduduki tanggakedua selepas kacang soya sebagai sumberutama bekalan minyak dan lemak dunia.Dewasa ini, Asia Tenggara merupakankawasan terpenting pengeluar minyak sawit dimana Malaysia merupakan pengeluar danpengeksport utama. Artikel ini mengulaspelbagai faktor yang telah membawa sawitkepada kedudukan sekarang termasuk dariaspek biologi, teknikal, pengurusan, alamsekitar dan sosio-politik.

Ciri-ciri biologi yang telah dikenal pastisebagai kritikal kepada produktiviti tinggitanaman tersebut diteliti. Ini termasuksifatnya yang saka dan sentiasa hijau(memberikan kanopi penutup sepanjang masamemintas sebahagian besar radiasi yangmendatang), penghasilan tandan buahsepanjang tahun dan penyaluran asimilasitinggi ke dalam tandan buah.

Aspek saintifik dan pengurusan yangtelah menyumbang kepada kejayaan sawittermasuklah pembaikan genetik yangsignifikan, penghasilan bahan tanamanbermutu tinggi, pembangunan danpenggunaan amalan agronomi yang telahdihalusi dan saiz ladang sawit yang sesuai disamping sistem perladangan yang mantap,R&D yang berterusan dan sokongan

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Oil Palm Bulletin 50

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INTRODUCTION

From its home in West Africa, the oil palm(Elaeis guineensis Jacq.) has spread throughoutthe tropics and is now grown in 16 or morecountries. However, the major centre ofproduction is in Southeast Asia (SEA) withMalaysia and Indonesia together accounting foraround 83% of world palm oil production in 2001.The recent changes in world mature areas areshown in Table 1. Malaysia is presently theworld’s leading exporter of palm oil having a 60%market share and palm oil is second only tosoyabean as the major source of vegetable oil.

TABLE 1. WORLD MATURE AREAS OF OIL PALM (‘000 ha)

Countr ies 1980 1990 2000 Annual growth rate (%)1990-2000

Indonesia 230 617 2 014 12.6

Thailand 15 94 199 7.8

Malaysia 805 1 746 2 941 5.5

Colombia 27 81 134 5.2

Others 151 527 731 3.3

Nigeria 220 270 360 2.9

Ivory Coast 100 128 139 0.8

Total 1 756 3 463 6 563 6.6

Source: After Yusof and Chan (2003).

Oil palm production in Malaysia presentlyoccupies around 3.7 million hectares of whichover two million are in Peninsular Malaysia andthe rest in the East Malaysian states of Sabahand Sarawak. Production is divided betweenlarge estates managed by publicly-listedcompanies, smaller independent estates,independent smallholders and governmentsmallholder settler schemes.

With good quality planting materials andagronomic practices, oil palm begins producingthe oil-bearing fruit bunches as early as two anda half years after planting. While the lifespan ofoil palm, as demonstrated by specimens plantedin the Bogor Botanic Garden, Indonesia, is atleast 120 years, the crop is generally grown for25-30 years before being replanted. This ismainly because old palms become too tall toharvest economically.

Both the public and private sectors carryout oil palm research and development (R&D). InMalaysia, the Palm Oil Research Institute ofMalaysia (PORIM) was set up in 1974 and wasmerged in 2000 with the Palm Oil Registrationand Licensing Authority (PORLA) to form theMalaysian Palm Oil Board (MPOB). MPOB nowdeals with all aspects of oil palm and palm oildevelopment and provides regulatory, trainingand technical advisory services to all sectors ofthe industry. Other research organizations thatconduct research on oil palm and palm oilinclude the Indonesian Oil Palm ResearchInstitute (IOPRI), Nigerian Oil Palm ResearchInstitute (NIFOR), CENIPALMA in Columbia,CIRAD in France and Bah Lias Research Station

infrastruktur yang baik yang dikendalikanoleh negara pengeluar utama.

Artikel ini juga mengupas programpembaikan tanaman melalui penggunaanpembiak baka dan kaedah pemilihan,pembangunan dan faedah teknik pembiakantampang melalui kultur tisu dan usaha yangberjalan untuk menggunakan teknik molekuldan kejuruteraan genetik bagi pembaikan danpengubahan komposisi minyak.

Akhir sekali, kualiti pemakanan minyaksawit sebagai satu komponen berkhasiat didalam makanan dibincangkan.

Keywords: oil palm, oil yield, breeding andselection, cloning and genetic engineering,sustainable production.


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in Indonesia. In Malaysia, there are also manylocal plantation companies with R&D facilitiessuch as FELDA, Golden Hope, UnitedPlantations and Applied Agricultural Research.

The intensive research on oil palm andpalm oil globally accounts for its significantcontribution and status in the oils and fatmarket. In Malaysia, the success of the oil palmis attributed to many factors, which includefavourable climatic conditions, well-establishedinfrastructure, management skills and technologyfor oil palm cultivation and a land ownershipstructure which favours estate type ofagriculture. Nevertheless, to stay competitiveand to ensure agricultural sustainability (that iseconomic, social and environmental), appropriateR&D in various disciplines such as cropphysiology, agronomy, genetics, tissue cultureand biotechnology, must be strategically plannedand implemented. The paper aims to provide acomprehensive overview on achievements in theareas mentioned and examine the potential of oilpalm as a sustainable crop in the future.

CROP PHYSIOLOGY

Understanding of basic physiological processes ofthe oil palm and how these relate to productionand management of the crop continues to be achallenging and active area of investigation.

Early work in Malaysia laid many of thefoundations needed for basic physiological,agronomic and breeeding studies by establishingnon-destructive methods of assessing leaf areaand dry matter production (DMP) (Hardon et al.,1969; Corley et al., 1971a). These have sincegreatly facilitated the estimation of productivityand its response to climatic and edaphicvariables (Squire, 1985; Henson and Chang,2000).

At this time also was first developed theidea that vegetative DMP takes priority overbunch DMP when assimilates are limiting(Corley et al., 1971b). This has proved to be avery useful concept in explaining palm responsesto planting density (Corley, 1973), edaphicfactors (Squire, 1985) and in the modelling ofproductivity (van Kraalingen et al., 1989).

Crop growth analysis in terms of lightinterception, light-use efficiency and partitioningof assimilates was first applied to oil palm bySquire (1984). This has proved to be a usefulapproach, permitting the relative importance ofthese aspects to be identified during crop

development. For young palms, the earlyexpansion of the oil palm canopy to facilitateradiation capture is of crucial importance foryield (Henson, 1991a), while the efficiency ofradiation conversion to dry matter becomes moreimportant later on once the canopy reaches fullexpansion (Henson and Chang, 2000). Theexploitation of the rapid leaf expansion trait inbreeding has been recommended by Breure(1985) while planters recognize the importancefor yield of ensuring good establishment throughoptimizing planting methods (Nazeeb, 1997).

It is now realized, that in addition toradiation and soil moisture, atmospherichumidity strongly influences photosyntheticcapacity of oil palm and that both humidity andradiation need to be considered when evaluatingclimatic effects on yields. Low humidity restrictsstomatal opening and hence CO2 uptake (Smith1989; Henson, 1991a). This finding may haveimplications for the location of new plantationsand for predicting responses to climaticperturbations such as haze events (Henson,2000).

Significant gaps in present knowledgeremaining to be filled include the amount ofassimilated carbon needed to maintain the rootsystem and the minimum root system requiredto serve the needs of the palm for water andnutrient uptake. Minirhizotron tubes with acamera attachment are currently being used tomonitor root turnover (Mohd Haniff and MohdRoslan, 2003). Combined with destructivesampling, this method should give a fullerpicture of root activity and total assimilaterequirements.

CROP PRODUCTIVITY

The oil palm has the distinction of being themost productive of all oil crops with an averageyield in major producing countries of about 3-4 tof mesocarp (palm) oil per hectare per year(Table 2). By contrast, the yields of mostcompeting oil crops are typically less than 1 t ha-1

yr-1. This means that the productivity of oil palmis at least three to eight times more than mostoilseed crops. Thus, only 7 million hectares of oilpalm are required to supply 20% of the worlddemand for oil and fats (1.09 billion tonnes),compared to the 80 million hectares of oilseedsneeded to supply another 24% of this demand(Murphy, 2003).

In addition, oil palm also produces c. 0.5 tha-1 yr-1 of kernel containing c. 47% kernel oil.


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The kernel and mesocarp oils differ in fatty acidcomposition and hence have different uses,including both food and non-food. The kernelmeal or cake is also of economic value as a sourceof animal feed protein.

Oil yields of the best plantings and in thepeak years of production are much higher thanthe above figures. As an example, on a coastalsoil with a high fertility status and constantwater supply, palms at nine years after plantinghad a standing dry biomass of 56 t ha-1 and anannual total dry matter production (TDMP) of36.7 t ha-1. The partitioning of TDM betweenfruit bunches (BDM) and vegetative dry matter(VDM) resulted in a bunch index (BDM/TDM) of0.46 and a harvest index (palm oil/TDM) of0.185, so the oil yield was 6.8 t ha-1. Thesefigures neglect the kernel oil. Since the mesocarpoil contains over twice the energy of VDM, thetotal non-oil equivalent biomass production wasover 44 t ha-1 yr-1 and the BI and HI in energyterms were 0.55 and 0.32 respectively.

How does the oil palm attain such yieldsdespite being a C3 photosynthesis crop? Firstly,its photosynthetic capacity is relatively high foran arborescent perennial, with the rate at lightsaturation approaching at least 25 µmol m-2 s-1

(Dufrene and Saugier, 1993). Secondly, at acommercial spacing of 130-150 palms ha-1, undergood conditions a full canopy cover is obtained bythe fifth to sixth year after planting when theleaf area index (LAI) is around 6. By 10 years,96% of photosynthetically-active radiation (PAR)is intercepted while the mean interception valueover the lifetime of a planting is about 88%(Squire and Corley, 1987). Thirdly, being atropical perennial crop with continuous year-round fruit production it is able to fully exploitresources provided limitations such as waterdeficits and pest and disease attacks areminimal.

YIELD POTENTIAL

There have been various attempts to estimatethe theoretical maximum yield of the oil palm.By combining the maximum levels observed forindividual yield components, Corley (1983)concluded that 17 t mesocarp oil per hectare peryear should be possible. Subsequently, an evenhigher value of 18 t ha-1 yr-1 was postulatedbased on additional considerations of dry matterpartitioning within the bunch (Corley, 1998).Breure (2003) in considering the matter further,concluded that a more realistic estimate, giventhe often mutually antagonistic relationshipsbetween yield components, would be from 10-11t ha-1 yr-1. This is similar to the maximum yieldsalready achieved in several trials (breeder’smaterials 10-12 t ha-1 yr-1) (Rajanaidu andJalani, 1990; Lee and Toh, 1991). In thecommercial setting, a company officially reportedthe oil yield of its nine plantations to range from6.51 to 7.45 t ha-1 yr-1. In general, with goodplanting materials, soil condition andagricultural practice, the average yields ofcommercial plantations range from 5 to 7 t ha-1

yr-1 (Henson, 1991b). The challenge is thereforeto narrow the gap between the national average/commercial yield and the yield potential, boththrough crop improvement and management.

CROP IMPROVEMENT

Breeding and Genetics

The four African Elaeis guineensis palmsbrought over by the Dutch in 1848, and plantedin Buitenzorg Botanical Garden (now Bogor)Indonesia laid the foundation for the oil palmindustry in Malaysia and Indonesia. From these,the Deli dura palms with unique and favourablefruit qualities were developed. The Deli durapopulation is widely utilized for seed production

TABLE 2. WORLD PRODUCTION, YIELDS AND AREAS OF OIL CROPS

Crop Production (‘000 t) Oil ha-1 yr-1 (t) Area (million ha) (%) Of total area

Soyabean 25 483 0.46 55.398 63.48

Sunflower 9 630 0.66 14.591 16.72

Rapeseed 14 237 1.33 10.704 12.26

Palm Oil 21 730 3.30 6.563 7.52

Source: After Yusof and Chan (2003).


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and in genetic improvement programmes inMalaysia and Indonesia. The most cultivatedhigh yielding oil palm variety, the thin shelledtenera [oil: bunch (O/B) >20%] is produced whenthe thick shell dura (O/B ~ 17%) crosses with theshell-less pisifera. The pisifera, which is femalesterile is used as the pollen source.

Apart from raising the total yield of freshfruit bunches (FFB), breeding and selection alsofocus on achieving high FFB oil and kernelcontent. The quality of the oil in terms of a highlevel of unsaturation [high iodine value (I.V)]and minor but important constituents such asvitamin E and carotenoids, is also being selectedfor. Vegetative characters are also taken intoaccount where reduced rates of trunk extensionand long bunch stalks are desirable attributes tofacilitate harvesting while compact palms mayallow higher planting densities of up to 180palms ha-1 (Basri et al., 2003).

Elaeis oleifera, an oil palm species endemicto South and Central America readily hybridizeswith Elaeis guineensis. This American speciesoffers several desirable traits including slowheight increment, high unsaturation andresistance to disease such as Fusarium wilt,which can be introgressed into the economicallyimportant Elaeis guineensis.

Previously, seed production solely relied onthe Deli dura as the maternal parent with theexclusive use of the AVROS pisifera as the pollensource. Systematic prospections to collect oilpalm genetic materials were carried out byMalaysian researchers to widen the genetic basefor breeding and to ensure conservation of palmgenetic resources. The collection for Elaeisguineensis started in Nigeria in the early 1970sfollowed by other countries in Western andCentral Africa and the Island of Madagascar(Rajanaidu and Jalani, 1994a, b, c). Elaeisoleifera genetic materials from six Central andSouth American countries were also collected(Rajanaidu and Jalani, 1994c). MPOB now hasthe largest oil palm germplasm collection in theworld. There is indication based on restrictionfragment length polymorphism (RFLP) analysisthat a high level of genetic variability exists inthe natural population from Africa, which can beexploited for genetic improvement throughbreeding and selection (Maizura, 1999).

These germplasm materials together withelite dura and pisifera have been used in thedevelopment of the PORIM Series (PS) ofplanting materials (now MPOB). High yieldingand dwarf palms (PS1) with potential oil yield of

7.7 t ha-1 yr-1 and height increment of only 40 cmyr-1 (PS1) compared to the normal 5-6 t ha-1 yr-1

and 45-75 cm yr-1 and high I.V palms (PS2) withI.V. in excess of 60 compared to 53 of currentplanting materials, were developed after intenseselection of the Nigerian germplasm collection.These materials have been distributed to the oilpalm industry for parallel development bycrossing with industry breeding materials andsubsequent large-scale field evaluation (Kushairiet al., 2000). Another planting materialdeveloped using the Nigerian germplasm is PS3(high kernel/bunch of 10%-15% compared to thenormal 5%-7%). More recent selections includePS4 (Elaeis oleifera with high carotene up to2220 ppm compared to 500-700 ppm inE. guineensis), PS5 (high vitamin E, of up to1247 ppm compared to the normal 500 ppm) andPS6 (high bunch index of 0.68 compared to 0.3 incurrent DxP).

Breeding programmes involving E. oleiferaare not being given as much emphasis as thosewith E. guineensis. Nevertheless, there areefforts in producing interspecific E. oleifera andE. guineensis hybrids for improving I.V. anddeveloping short and compact palms (Escobarand Alvarado, 2003; Chin et al., 2003). Due toinferior fruit set and problems associated withexcessive vegetative vigour of the F1 hybrids, aseries of backcrosses to E. guineensis areessential to improve the yield and vegetativecharacters. Programmes to map the oil palmgenome by MPOB and CIRAD using RFLP,AFLP and macrosatellite probes will enablemarker-assisted selection to be carried outeventually (Rajinder et al., 2001). In addition,the genomic in situ hybridization technique(Madon et al., 1999), which can differentiate thegenome of the two species, proved a valuable aidto breeders in monitoring the inheritance ofE. guineensis in the backcross progenies.

Tissue Culture

The earliest reports of successfulvegetative propagation of oil palm by tissueculture were in the mid 1970s (Jones, 1974;Rabechault and Martin, 1976). Now, about 20 oilpalm laboratories are in operation throughoutthe world with capacity ranging from 10 000 –200 000 plantlets per year (Zamzuri et al., 1999).As compared to seed production, tissue culture ofoil palm offers several advantages (Sogeke,1998). It allows rapid multiplication of uniformplanting materials with desired characteristics.This enables improvement of planting materialsusing existing individuals which have all or mostof the desired qualities such as good oil yield and


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composition, slow vertical growth and diseaseresistance. Additionally, it also opens newavenues for producing novel planting materialsvia genetic engineering because tissue cultureis the means for regeneration of tissuestransformed with genes for traits of interest.

Oil palm tissue culture is employed both asa means for producing good tenera palms forcommercial planting and to multiply goodparents (both dura and pisifera) for seedproduction. It is also practised to expedite theexploitation of progenies from interspecificE. oleifera x E. guineensis crosses. Based oncurrent demand for oil palm seeds in Malaysiaand other countries, Zamzuri et al. (1999)estimated that there is a ready market for morethan 100 million tissue culture plantletsannually.

Tissue culture laboratories are linked toan effective oil palm breeding and improvementprogramme to ensure supply of desired explants.Ortets selected are supported by at least fouryears of field data showing good performance onoil yield, vegetative characteristics such as lowheight increment and physiological traits such asbunch index and oil characteristics (Rohani etal., 2000). Oil yield is determined by the oilextraction rate (OER) or O/B and weight of FFB.Since O/B has been demonstrated to be highlyheritable and transmitted from ortets to ramets,it is given emphasis in ortet selection. Leaves,inflorescences and roots can be used as explantsbut young leaf spears are often preferred. Leafexplants can be easily surface sterilized and givehigher clonability rates (Rajanaidu et al., 1997).From the explants, callus is initiated, followed byembryogenesis, shoot and root regeneration,hardening of ramets for the nursery and finallyfield evaluation. The regeneration processthrough oil palm tissue culture takes two to fouryears depending on genotype. Zamzuri (1998)introduced the double-layer rooting technique foroil palm. In this technique, the solid shootdevelopment medium is overlayed with liquidroot initiation media. This improves theproductivity of the worker 18-fold and reducesthe cost of rooting by about 94%.

Based on field performance data fromvarious sources, an improvement of oil yieldbetween 20% to 30% over seedling plantingmaterials is achievable by clonal materials (Sohet al., 2001). There are indications that selectionfor resistance to major oil palm diseases will beeasier based on differences in susceptibilityshown by clones to Ganoderma, Fusarium andblast (Purand-Gasselin et al., 1999). The

difficulty lies in achieving true-to-typereproduction of plants selected as ortets,especially with the incidence of mantledabnormality. The percentage of abnormality inthe field has generally been maintained at atolerable level of less than 5% (Maheran et al.,1995). Prudent selection of good ramets at bothin vitro and nursery stage is practised to reduceabnormality level. Maheran et al. (1995) reportedthat clones appearing normal at both stages gavea low level of abnormality in the field (about2.2%). It was estimated that the initialinvestment on clonal materials will be covered inthe sixth year (Zamzuri et al., 1999), after whichthe returns from clonal materials will be muchhigher than conventional dura x pisiferaplanting materials due to their higherproductivity.

Favourable reports of plantings of liquidculture ramets suggested that the technology canbe exploited for oil palm clone production (Soh etal., 2001). The liquid culture system offersadvantages in reproducibility, versatility andefficiency with high potential for scaling uppropagule production. In parallel withdeveloping a liquid culture system, MPOB isemploying bioreactor technology which will leadtowards a semi or full automation of the processof oil palm clonal production (Tarmizi et al.,2003).

Recent results from genetic marker andgenome wide methylation studies indicated thatthe tissue culture abnormalities in oil palm arisefrom an interplay of genetic and epigeneticmechanisms. Various efforts are geared towardsdeveloping diagnostic tools for predicting geneticpredisposition to abnormality. These includeglobal gene expression analysis via DNAmicroarray, genetic mapping and the candidategene approach. It is anticipated that an effectivescreening process, preferably at the ortet stage,will provide greater confidence to the industry inproducing and utilizing clones (Cheah, 2003).

Genetic Engineering

Production of novel high value products bygenetic engineering provides avenues fordiversification to increase the economic value ofoil palm. The oil palm being highly productiveand perennial in nature has significantadvantages over other crop species for suchendeavours. MPOB’s first initiative in geneticengineering is to produce high oleate palms forthe industrial feedstock and liquid oil market.The estimated value for high oleate palms isUSD 1500 ha-1 yr-1 if the oleic acid content is


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Figure 1. Fatty acid biosysnthesis in plants (FAS = fatty acid synthase).

>65%. More recent targets in geneticmanipulation include high stearate palms ascocoa butter substitute, nutraceutical oilsenriched in palmitoleic acid and lycopeneand biopolymers for industrial applications(Sambanthamurthi et al., 2002).

Palm fruits have two storage tissues;mesocarp and kernel that can be the target foraccumulating genetically manipulated products.The substrates and intermediates for theproduction of storage oil or protein in thesetissues may be channelled to alter the levels ofexisting products or to produce novel value-added products without deleterious effects on theplants. The mesocarp and kernel oil differ infatty acid composition as well as the period atwhich the oil accumulates during oil palmfruit development. The promoter sequencescorresponding to a mesocarp and a kernel-specific gene of the oil palm have been isolated.The expression profile of the mesocarp-specificgene in different oil palm tissues, as well as atdifferent developmental stages of the mesocarpand at the cellular level (as shown by Northernblot analysis and RNA in situ hybridization,respectively) indicated a strong correlationwith that of a fatty acid biosynthetic gene,stearoyl-ACP desaturase. Transient expressionanalysis of oil palm tissues bombarded withpromoter:reporter construct further confirmedthat the promoter corresponding to the mesocarpspecific gene is functional with a mesocarp-specific promoter activity (Siti Nor Akmar andZubaidah, 2002). Backbone transformationvectors containing the mesocarp-specificpromoter, nopaline synthase (NOS) terminator,

with and without plastid targeting sequencefrom oil palm stearoyl-ACP desaturase genewere produced. In these constructs, a rare cuttersite was introduced (Asc I) to serve as the site forinsertion of target genes (Siti Nor Akmar et al.,2003).

The production of high oleate and highstearate palms involves genetic manipulation ofthe fatty acid biosynthetic pathways in themesocarp (Figure 1). Biochemical studies andgene isolation were carried out for importantenzymes required for the production of thesefatty acids (Siti Nor Akmar et al., 2001). Apartial cDNA clone encoding acetyl-CoAcarboxylase (ACCase), an enzyme catalyzing thefirst committed step in lipid biosynthesis andexpected to be an important flux-controllingenzyme has been isolated. β-Ketoacyl ACPsynthase II (KAS II) and acyl-ACP thioesteraseare the key enzymes for genetic manipulation forthe production of high oleate and stearate palms.The strategy is to over-express KAS II whichcatalyses the elongation from C16:0 to C18:0 andto antisense palmitoyl-ACP thioesterase in orderto reduce the production of palmitate forchanneling towards increasing oleate.Biochemical studies have been performed onboth enzymes and the full-length cDNA cloneshave been obtained and used in producing geneconstructs containing mesocarp-specific promoterfor transforming oil palm. To avoid spill overfrom C18:1 to C18:2, down regulation of theoleoyl-CoA desaturase is essential. Thus far, thepartial cDNA clone encoding this gene has beenisolated. The full-length cDNA clone for stearoyl-ACP desaturase has been isolated and the

FAS pathway

β-ketoacyl-ACPSynthase II

C16:0-ACP(palmitoyl-ACP)

Palmitoyl-ACPthloesterase

C16:0(palmitic acid)

C18:2-CoA(linoleoyl-CoA) C18:1-CoA

(oleoyl-CoA)

C18:1(oleic acid)

Oleoyl-CoAdesaturase

C18:0(stearic acid)

C18:1-ACP(oleoyl-ACP)

Stearoly-ACPdesaturase

C18:0-ACP(stearoyl-ACP)


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antisense form introduced into palms forincreasing stearic acid.

The genetic engineering programmeinvolves collaboration and co-ordination betweenvarious research disciplines namely themolecular biologists to provide the genesand promoters and to carry out oil palmtransformation, tissue culturists for regeneratingthe transformed tissues and breeders to assistwith field evaluation. The particle bombardmentmethod has been developed and is nowbeing used routinely for transforming oilpalm (Parveez, 2000). Research to establishthe Agrobacterium mediated transformationtechnique is also being intensified. MPOB hasalso set up an Institutional Biosafety Committeeto address the various issues related to GMpalms and field release of transgenic palms forevaluation. To date, there is no geneticallymodified palm oil though active R&D is inprogress.

CROP MANAGEMENT

Agronomy and Nutrition

The oil palm is recognized as having a highdemand for nutrients; not surprising in view ofits high dry matter production. Nutrients thatare removed continuously through the harvestedFFB or sequestered in the standing biomassneed replacing if soil nutrient reserves are not tobecome depleted. From previous studies, it hasbeen estimated that for Malaysian soils, between0.5 and 1.1 kg palm-1 yr-1 of N, 0.7 and 1.1 kgpalm-1 yr-1 of P2O5, and 0.5 to 2.0 kg palm-1 yr-1 ofK2O are needed to make good the shortfall in soilnutrient supply after taking into accountexpected losses of the applied nutrients (Tarmizi,2000). In addition, it is important that for yieldsto be maximized, the nutrients applied arebalanced.

Past studies have shown that empty fruitbunch (EFB) mulching significantly improved oilpalm yield (Hamdan et al., 1998). EFB generallycontains 0.80% N, 0.22% P2O5, 2.90% K2O, and0.30% MgO on a dry weight basis. Yieldimprovement ranging from 5% to 23% has beenachieved depending on soil type. Hamdan et al.(1998) showed that nutrients from 60 t ha-1 yr-1

of EFB, without any inorganic fertilizer, weresufficient to support palm growth. Nevertheless,because of the high C/N ratio, a lower rate ofEFB application is made with supplements ofinorganic fertilizer. This approach maintains soilproductivity through better soil structure and

reduces fertilizer cost for immature palms by asmuch as 58%, and by 5% for mature palms.

The high cost of inorganic fertilizerencourages best-developed practices designed tooptimize fertilizer use and minimize nutrientlosses. For example, it is routine to base fertilizerrecommendation on foliar analysis so thatobserved deficiencies can be corrected and anappropriate balance maintained betweendifferent elements. Foliar analysis may besupplemented by analysis of rachis tissue (whichacts as a nutrient store) and soil. Using suchinformation, application rates and fertilizersources are objectively determined, often withthe aid of customized computer programmessuch as the MPOB Oil Palm Nutrient System(OPENS). The technology for producing afertilizer management map has been developedfor oil palm and current investigation is onvariable rate technology (VRT) required for theimplementation of precision agriculture.

An innovative replanting technique hasbeen developed where young palms are planteddirectly amongst old crop residue piles toimprove accessibility and efficiency of nutrientutilization (Khalid et al., 2000). This techniqueoffers greater synchrony between nutrientrelease and plant uptake in terms of space andtime compared to the standard practice. Theresidues contain 642 kg N, 58 kg P, 1384 kg Kand 156 kg Mg per ha. In terms of inorganicfertilizers, this is equivalent to 3.06 t of sulphateof ammonia, 0.37 t of Christmas Island rockphosphate, 2.77 t of muriate of potash and 1.0 tof kieserite.

Environment

Increasingly, there is recognition world-wide of the necessity to reconcile agriculturepractices with the need for environmentalconservation. Ensuring that agricultural opera-tions do not damage the environment also, in thelong-term, contributes to the sustainability ofcropping systems.

In several areas, environmental considera-tions are already well catered for. These includethe minimum use of chemicals, the adoption ofintegrated pest management, judicious use ofinorganic fertilizer, recycling of palm biomasswithin the plantation and between mill andplantation, zero-burning practice on clearance,and soil conservation measures. Examples of thelatter including terracing of hilly areas,construction of drains and preservation ofnatural watercourses, use of silt pits and of cut


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fronds across slopes to minimize erosion andrunoff.

The use of beneficial plants, such asCassia cobanensis and Euphorbia heterophylla,as sources of nectar for parasitoids, is beingwidely adopted by plantations to keep populationsof oil palm insect pests in balance with nature(Basri and Norman, 2000). This has led to areduction in the use of insecticides for bagwormand nettle caterpillar control.

Several features of an oil palm plantationresemble those of the natural forest cover that itoften replaces. As a perennial tree crop, oil palm,at least from the seventh or eighth year onward,provides a continuous and dense canopy coverand also recycles nutrients and organic matterwithin the ecosystem. Unlike most other oilcrops, little or no tillage is involved in itscultivation which minimizes the oxidation andloss of organic matter which may otherwiseoccur. The canopy not only provides protection tothe soil from the worst impacts of heavy rainfall,it also increases humidity while reducing air andsoil surface temperatures, all factors which gotowards providing a favourable microclimate formany co-existing species.

Environmental considerations are equallyimportant in the processing sector of theindustry. Legislation imposes limits to thenature and amounts of discharges to theatmosphere and waterways by mills andrefineries. However, mill waste products, whichwere once viewed as embarrassing liabilities arenow viewed as co-products of increasingpotential value. In addition to EFB and palm oilmill effluent (POME) as nutrient sources inthe plantation, the use of excess fibres inmanufacturing, the recovery of POME solid foranimal protein, the generation of biogas from theeffluent ponds and use of surplus boiler energy togenerate electricity, are further examples, all ofwhich serve to promote a zero-waste concept.Current effort on R&D at MPOB is to minimizethe production of greenhouse gasses (GHG) andall existing practices in the field, mill andrefinery are being examined. Reduction of GHGwill assist in slowing down of climate change.

Crop Oil Quality and Nutritional Value

While palm oil has a wide range of uses,both food and non-food, some 80% of the oilproduced serves as an important source ofvegetable fat for an increasing number of people.The crude oil comprises approximately halfsaturated (mainly palmitic) and half unsaturated

(mainly oleic) fatty acids. Saturated fats have inthe past been widely regarded as beingundesirable dietary components due to theirassociation with high cholesterol levels and heartdisease. However, there are various forms ofcholesterol, not all bad, and recent studies haveshown that intake of palm oil raises levels of thehigh-density lipoprotein (HDL, good cholesterol)at the expense of the low-density lipoprotein(LDL, bad cholesterol).

Unsaturated oils such as soyabean areusually hydrogenated to render them less liquidand more suitable for the manufacturing ofmargarines and other products. This essentiallyconverts them into saturated fats while at thesame time generating trans-fatty acids that donot occur naturally. As such, trans isomers havebeen found to impose a risk of heart disease, andthere is now a preference for trans-free oils suchas palm oil. Palm oil is therefore promoted bothas a balanced oil (having equal saturated andnon-saturated content) and one that is trans-free(Wahle and James, 1993; Ascherio, 2002).

Other plus points, already referred toabove, concern the vitamin and carotenoidcontents of the oil. Vitamin E is a free radicalscavenger, with anti-cancer properties, as arethe carotenes. Red palm oil, which is the productof a new technology that aims to preserve theseminor components, has a further role to play ina healthy diet. More recently, it has been shownthat the oil palm is a rich source of phenolicantioxidants, a minor fraction of which entersthe oil phase and confers further health benefits.

Thus, from the many studies nowundertaken, the image of palm oil as anundesirable tropical oil has changed and it isnow accepted worldwide as a healthy dietaryingredient.

OIL PALM POTENTIAL – SOMECONCLUSIONS

Palm oil is an important food and a major sourceof lipids. World population continues to increase,thus creating increasing demand. As such, oilpalm will continue to be cultivated worldwide.The growing of oil palm needs to be economicallyviable and environmentally sustainable. This isaided by intensive R&D on the crop, aspects ofwhich have been discussed in the paper.

The effort to narrow the gap betweencommercial yield and potential yield willcontinue to be given priority. Materials, which


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produce 7 t oil ha-1 yr-1 in commercial planta-tions, have been produced. The low overallnational yield averages suggest that besides goodplanting materials, good crop management andenvironment are critical for the realization ofyield potential. In addition, it is important thatthe plantations quickly adopt new technologies,particularly in fertilizer management. Thepossible adoption of precision agriculture in thefuture will further optimize fertilizer applicationso that achieving site yield potential can be areality. This will be a challenge for researchers,extension agents and plantation managers.

An understanding of the basic physiologyof the palm can enhance its management as adecision can be based on scientific rationale.There is a need, however, to develop an oil palmmodel that examines all physiological factorsassociated with productivity in relation todifferent environmental conditions. From thismodel, an ideal type palm can be generated forvarious soils and environments.

Current breeding and genetics effortsworldwide are focused on high oil yield per unitarea of land with a view to maximizing returns.This will continue to be the challenge in thefuture until the yield potential of each site isfully achieved. Besides oil yield, breedingpopulations with many desired traits such ashigh carotene and high vitamin E have beenidentified as mentioned. The close collaborationbetween MPOB and the private sector willensure that these traits will eventually becommercially exploited. This should be possibleafter 10 years of progeny evaluation resulting inproducts whose values are much higher thancurrent palm oil. This will add more strength tothe economics of oil palm cultivation.

Concurrently, within MPOB, a multi-disciplinary team has been formed to work onthe development of high carotene from E. oleiferaas a nutraceutical product. The aim is to producehigh carotene-containing capsules.

Other areas where intensive R&D havebeen undertaken to create value addition includebiomass and oleochemicals. Many technologies toconvert oil palm biomass into valuable productssuch as pulp and paper, medium density fibre-board (MDF), moulded particleboard, plywoodand lumber have been developed. Oneremarkable success is the utilization of oil palmfibres as fillers for the production ofthermoplastic composite used in the Malaysiannational car. Unending efforts are being madetogether with the industry to commercialize theother products.

Oleochemicals are essentially chemicalsderived from natural plant oils and fats. Theyare important because they can be furtherprocessed into high value-added products. Toexpedite research in this area, the AdvancedOleochemical Technology Centre was establishedat PORIM in 1994 to spearhead the developmentof downstream activities related to oleochemicals.The centre focuses on polyurethanes, polyols,inks, surface coatings, palm-based herbicides,surfactants and cosmetics. Pilot plants such asthose for polyol and the methyl ester sulphonatesare built as a step towards commercialproduction.

In the past, the production of clonesthrough tissue culture has been plagued withhigh occurrences of abnormality. To date, thereis a much better understanding of the factorsassociated with abnormality and on how toreduce its incidence though the problem has notbeen fully resolved. However, the level ofabnormality in the field is now less than 5% andseveral major plantation agencies are beginningtheir replanting programmes with clones. Such amove will result in yield increasing by as muchas 30%. The development of suspension cultureand bioreactor technology will further allowclones to be produced over a shorter periodcompared to the use of traditional solid culture.

Significant advances have been made in oilpalm genetic engineering over the last 10 years.Virtually all the genes and promoters required tomodify the fatty acid biosynthetic pathway havebeen obtained. Technology is currently availableto produce three novel products, namely higholeate, high strearate and high palmitoleate.Nevertheless, several pressing issues need to beaddressed in the immediate future such asdeveloping a better transformation method withlow copies of trans-genes, and ensuring bio-safety, and public acceptance.

This article demonstrates that the R&D onoil palm has also aimed to fulfil environmentalneeds. Any good agricultural practice needs to bebacked by supporting evidence. The industry asa whole is serious in promoting environmentalsound practices and these are increasingly beingadopted.

Thus, for the future, the oil palm is gearedto undergo a more efficient production systemthat will produce more yields, thus translatinginto lower production costs. The potential of oilpalm is enormous and many opportunities existfor the creation of new industries. Thesustainability of oil palm will gain more ground


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as results of future R&D unfold for adoption bythe industry.

ACKNOWLEDGEMENT

The authors would like to thank the Director-General of MPOB for permission to present thispaper. Comments made by Dr Chan, K C, on themanuscript and Dr K Sundram on nutritionalissues are appreciated.

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