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VOLUME 10 NO.2, December 1998

STAGES IN THE VEGETATIVE PROPAGATION OF OIL PALM, Elaeis guineensis Jacq. THROUGH TISSUE CULTURE.

Sogeke A K

Oil palm  (Elaeis guineensis Jacq.) was vegetatively propagated by tissue culture in NIFOR on a NAA medium which provided a very short callus stage. The following stages were identified: callus (initiation and maintenance), embryoid, plantlet (ramet), prenursery (sand culture), nursery, and field planting. Normal male and female inflorescences which led to normal fresh fruit bunches (FFB), were produced by the tissue culture palms two and a half years after planting the plantlets in the field.

FORCE AND ENERGY REQUIREMENTS FOR CUTTING OIL PALM FROND

Abdul Razak Jelani, Desa Ahmad, Ahmad Hitam, Azmi Yahya And Johari Jamak

A study was conducted to investigate the effect of cutter design, cutting angle and frond maturity on the specific cutting force (FOCSA) and energy (ENCSA) requirement per unit cut area for cutting oil palm fronds. Two designs were tested, (i) sickle cutter and (ii) claw cutter. Cutting angles of
90? , 60? , and 45? , were tested on the three levels of frond maturity.

The results showed significant effects of cutter design, cutting angle, frond maturity and interaction of cutter design and cutting angle on FOCSA and ENCSA requirement for cutting oil palm fronds. The maximum FOCSA for the sickle and claw cutters were 12.2kg / cm?  and 22.9kg / cm?  respectively. while the maximum ENCSA for the sickle cutter and claw cutters were 65.4kg-cm / cm?   and 115.5kg-cm / cm?  respectively. This indicated that the sickle cutter required 47% less FOCSA and 76.5% less ENCSA than the claw cutter. Increasing the cutting angle resulted in higher FOCSA and ENCSA requirements. Also, the more mature the frond, the higher the FOCSA and ENCSA required to accomplish the cutting.

NOTES ON OIL PALM PRODUCTIVITY.
II. AN EMPIRICAL MODEL OF CANOPY PHOTOSYNTHESIS BASED ON
RADIATION AND ATMOSPHERIC VAPOUR PRESSURE DEFICIT

I E Henson

Using data on daytime CO?  flux above the canopy determined by eddy correlation, a simple empirical model was devised based on relationships between CO?    flux and radiation, and CO?    flux and atmospheric vapour pressure deficit. The model satisfactorily predicted above-canopy flux from measurements of these variables using site-specific regression constants. The limitations and practical implications of the model are discussed.

BIOLISTIC-MEDIATED DNA DELIVERY AND ISOLATION OF TRANSGENIC OIL PALM (Elaeis guineensis Jacq.) EMBRYOGENIC CALLUS CULTURES

Ghulam Kadir A. Parveez And Paul Christou

Oil palm (Elaeis guineensis Jacq.) embryogenic calli were transformed with plasmids containing various combinations of genes encoding ?-glucuronidase, phosphinotricin acetyltransferase and hygromycin phosphotransferase, using an electric discharge particle bombardment device. Experiments to optimize the accelerating force for DNA delivery into embryogenic tissue of oil palm were carried out. Selection and culture conditions to allow recovery of transgenic tissue are reported. Stable integration of transgenes was confirmed by molecular analysis. Due to the long time required for regeneration of transgenic plants from oil palm embryogenic callus, this report is significant as it describes, for the first time, conditions leading to the recovery of transgenic  embryogenic callus cultures carrying and expressing transformed marker genes.

NOTES ON OIL PALM PRODUCTIVITY.
III. THE USE OF SAP FLUX PROBES TO MONITOR PALM RESPONSES TO ENVIRONMENTAL CONDITIONS

I E Henson

Using a system developed in France, relative sap flux was measured in trunks and fronds of palms in relation to the potential evapotranspiration (PET) and evapotranspiration (ET) rates deduced from micrometeorological measurements. The method provided a sensitive means of detecting changes in transpirational activity related to radiation, PET, soil water supply and frond aging. Its further use and development are discussed.

THE EFFECT OF PALM-BASED SURFACTANTS AS SPRAY ADJUVANTS IN GLYPHOSATE ISOPROPYLAMINE (IPA)

Ismail A R, Dzolkifli O, Ooi T L And Salmiah A

The utilization of some palm-based surfactants in glyphosate isopropylammonium (IPA) formulations were tested. Three groups of ninionic surfactants were used, i.e, fatty alcohol ethoxylate (FAE) with five moles of ethylene oxide (EO), 7 EO, 9 EO and 20 EO, fatty amine ethoxylate (FAmE) and alkylpolyglycosides (APG). Cyperus rotundus, a thin-left and tuber-producing weed was used to test the efficacy of glyphosate IPA formulations.

Twelve glyphosate IPA formulations were prepared and their stabilities tested at room temperature (RT) and 45?C. All the formulations were stable at RT, and nine appeared as one layer after keeping at  45?C  for seven days.

Efficacy tests were carried out under full sunlight. The application rates were carried out under full sunlight. The application rates were 2.0kg / ha, 1.5kg / ha and 1.0kg / ha of glyphosate IPA, the active ingredient (a.i) per hectare (ha), and the spraying volumes used were 200 1/ha and 400 l/ha. The surfactant concentrations in the spraying solutions varied from 0.1% to 0.35% (w/w). Visual observation and analysis of  variance showed that six formulations gave very promising results for controlling  Cyperus rotundus. The formulations were FAmE, FAE(20EO), FAmE/APG(C8-C10), FAmB /APG(C8-C16), APG(C8-C10), and APG (C8-C16).

TECHNIQUES FOR SAMPLING OIL PALM ROOTS.
II. ROOT AUGER FOR PEAT SOILS

Mohd. Haniff Harun

Root study in peat is important for understanding the oil palm performance under this limiting soil condition. Difficulties arise  when studying roots in peat due to its structureless properties. A suitable auger was designed to ease root sampling in peat .The auger enables the extraction of a peat core sample of 10cm diameter by one metre length. Compression of the peat core sample was reduced and root excisions were  satisfactory.

VOLUME 10 NO.1

HYDROXYSTEARIC COMPOUNDS FROM UNSATURATED PALM FATTY ACID

Rakmi A. Rahman And Supriyadi Sadi.

Initial studies on hydroxylation of unsaturated palm fatty acids were carried out with very promising results. Hydroxylation of unsaturated palm fatty acids with hydrogen peroxide-acetic acid for two hours gave products with melting points of 79°C - 128°C C, acid values of 135-165, saponifiable values of 119-128 and hydroxyl values of 384-440. Yield of the product was about 80% - 90%. The product characteristics were very different from those obtained from other oils. For example, hydroxy fatty acid from sunflower oil has a saponifiable value of 212, acid value of 140 and hydroxyl value of 222 (Dahlke et al., 1995).

The product obtained in this study was not only 9, 10-dihydroxystearic acid but also some fatty acids and 10-oxo-stearic acid. By adding hydroxystearic acid at a concentration of 0.2%, the life of steel was extended by up to 10 times, showing that hydroxystearic acid was very effective as a rust inhibitor. Therefore, hydroxylation of unsaturated palm fatty acid is a promissing process for obtaining hydroxystearic compounds.

PALM BASED SULPHONATED METHYL ESTERS AND SOAP

Salmiah Ahmad, Zahariah Ismail And Jasmin Samsi.

Malaysia currently has the capacity to produce about 20% of the world's production of basic oleochemicals such as fatty acids, fatty methyl esters, other fatty alkyl esters, fatty alcohols and glycerol. Besides basic oleochemicals, there are also capacities to produce other derivatives such as mono and diglycerides, soap noodles, metalic soaps and ethylene bisstearamide.

Alpha-sulphonated methyl ester (a-SME) is an anionic surfactant that has frequently been mentioned. Due to its good detergency and less sensitive to water hardness, it could be used as a soap additive. However, a-SME received commercial significance only in Japan. Due to the availability of fatty methyl esters, which is the raw material for the production of a-SME and can be the raw material for the production of soap, it is worthwhile to consider utilizing these (fatty methyl ester and soap) to the best for Malaysia.

This paper reports on the washing behavior of a-SME based on palm fatty acid distillates, palm stearin and pure fatty acids produced on a pilot plant scale. The detergency of a-SME from palm stearin and palm fatty acid distillates were found to be similar and comparable to LAS and FAS. a-SME was also found to be mild towards the enzyme Savinase. As expected, the detergency of soap is increased via the addition of a-SME, and, at room temperature, the combination of (C12 soap:C14 - a SME) was better than (C14 a soap:C14 a-SME) and which was, in turn, better than (C14 soap:C12 a-SME).

ANALYSIS OF OIL PALM PRODUCTIVITY
III. SEASONAL VARIATION IN ASSIMILATE REQUIREMENTS, ASSIMILATION CAPACITY, ASSIMILATE STORAGE AND APPARENT PHOTOSYNTHETIC CONVERSION EFFICIENCY

I.E. Henson And S.H. Chai

Total productivity of oil palm growing at two sites in West Malaysia was assessed on a monthly basis over three to four years aided by a method for calculating monthly bunch dry matter production. The level and seasonal variations in production were compared with those predicted by a simulation model of oil palm growth which used solar radiation and leaf area index as the main inputs. Deviations between measured and modelled productivity were catered for by invoking changes in assimilate storage. The contribution to the seasonal yield pattern, by changes in assimilation capacity (via changes in radiation and leaf area index) and storage pool size were assessed for each site. The influence of variations in sink strength on the system is discussed.

INCIDENCE OF POTYVIRUS DISEASE IN OIL PALM NURSERY SEEDLINGS

J.J. Solomon And M. Kochu Babu

Oil palm seedlings raised in some nurseries in Karnataka State, India exhibited mosaic, mottling and ringspot symptoms indicative of virus infection. The incidence was in the range 0.001%-0.01% and was mostly observed in material imported from Costa Rica (ASD). Electron microscopic examination of leaf sap revealed flexuous filamentous particles, ultra-thin sections of symptomatic leaves showed pin wheel inclusions and scrolls in mesophyll tissues, characteristic features of poty virus. This paper highlights the virus incidence in the introduced material and its implications for quarantine.

NOTES ON OIL PALM PRODUCTIVITY
1. PRODUCTIVITY AT TWO CONTRASTING SITES

I.E. Henson

Yields at an inland and a coastal site planted two years apart, were examined from the start of bunch harvest up till the tenth (inland) or twelfth (coastal) years after planting. Both monthly and annual trends in bunch dry matter production were examined in terms of the development of yield 'cycles' and yield levels, respectively. Cycles were most pronounced at the more productive coastal site. There was evidence for external factor(s) modifying timing of yield peaks. Differences in yields between sites involved differences in bunch and female inflorescence numbers; the later due mainly to altered sex ratios.

The yield differences were accompanied by differences in vegetative dry matter production, dry matter partitioning and standing biomass, and involved variation in both radiation interception (via differing leaf area indices) and photosynthetic conversion efficiency. The contribution of genotypic variation to the observed differences was not determined.

CYTOLOGICAL ANALYSIS OF Elaeis guineensis AND Elaeis oleifera CHROMOSOMES

Madon, M; Clyde, M.M. And Cheah, S.C.

Cytological analysis performed on metaphase chromosome spreads of two oil palm species, E. guineensis (tenera) and E. oleifera, showed that both species have 2n=32 chromosomes. Paired t-tests showed no significant difference between paired homologues of E. oleifera whereas for E. guineensis, pair 7 showed a significant difference between the homolouges. For both species, based on chromosome length, pair 1 was assigned to Group 1, pairs 2-9 to group II and pairs 10-16 to group III. For E. guineensis and E. oleifera, Group 1 consists of the longest chromosome (10.98% and 10.69% of total haploid chromosome length respectively), Group II of medium length chromosomes (5.86%-8.79% and 6.05%-8.49% of total haploid chromosome length respectively) and Group III of medium short chromosomes (3.22%-5.47% and 3.01%-5.69% of total haploid chromosome length respectively). Paired t-tests performed for homologue chromosome pairs of E. oleifera and E. guineensis showed no significant difference in chromosome length between them. This is expected due to the fact that the two species can be crossed.

TECHNIQUES FOR SAMPLING OIL PALM ROOTS 1. MOTORISED ROOT SAMPLER

Mohd. Haniff Harun

Root study is an important aspect of research for understanding how plants interact with the environment. However, sampling of roots is an arduous task. A technique using a motorised hammer and a STIBOKA soil column cylinder was found to greatly enhance the sampling of oil palm roots in mineral soil. It enables a team of three workers to rapidly sample roots from a palm in a day.

VOLUME 11 NO. 2, December  1999

AGRONOMIC PERFORMANCE AND GENETIC VARIABILITY OF Dura x Pisifera PROGENIES.

Kushairi, A; Rajanaidu, N; Jalani, B S And Zakri, A H.

Wide variations for bunch yields, bunch quality components and morphophysiological traits were noted among 52 dura x pisifera (DxP) progenies derived from a North Carolina Model I mating design. Exceptional fresh fruit bunch yields were achieved by progenies producing high bunch number of moderate sized bunches. Progenies producing bunches of high fruit (F/B), mesocarp (M/B) and kernel (K/B) contents achieved out-standing production of total economic products (TEP). Tall progenies, on average, had higher TEP attributed to the higher ratio of bunch dry matter to vegetative dry matter. Correlations among the economically important component traits were generally meaningful  and any significant change in yield involved an increase in the number of bunches. Analysis of variance for yield and bunch quality components showed substantial genetic variation with several traits showing male effects, indicating additive gene action. The results suggested  that palm height is inherited through the male parent. However, further introgression of the pisifera parent is required to improve the economic yield of its shorter progenies. Estimates of genetical variance components of data pooled over replications were higher than those of the individual replications, with the highest estimates from data pooled over years. Pooling of data reduced the error variances, suggesting seasonal effects and, therefore, more years of data are necessary for efficient selection programmes. The Serdang pisiferas, 20A/112 and 20A/8, introgressed with AVROS pisifera generated DxP progenies with high kernel yield, while those arising from AVROS x S27B pisiferas produced high oil yields. The mean performance and genetic structure of the materials suggested that the potential parental genotypes for high overall oil yields are the duras of Ulu Remis, Banting, intracrosses of the Elmina, and the pisiferas of Lever Cameroon, Lever Nigeria and introgressed Serdang x AVROS.

IMPACT OF Metarhizium anisopliae ( DEUTEROMYCOTINA: HYPHOMYCETES) APPLIED BY WET AND DRYINOCULUM ON OIL PALM RHINOCEROS BEETLES, Oryctes rhinoceros (COLEOPTERA: SCARABAEIDAE)

Ramle Moslim; Mohd Basri Wahid; Norman Kamarudin; Mukesh Sharma And
Siti Ramlah Ahmad Ali

Four local isolates of Metarhizium anisopliae (Bp, Mo, Ma and Ml) were bioassayed against larvae of Oryctes rhinoceros in the laboratory. The larvae were surface-sterilized in 0.3% sodium hypochlorite and dipped into spore suspensions containing 108 conidia Ml-1. Of the four isolates, two long-spored isolates (Bp and Mo) were highly pathogenic against the beetles. Both isolates caused 100% mortality within 12 days of treatment and caused 71% to 75% mycosis. The times required to kill 50% (LT50) of Oryctes larvae for isolates Bp (LT50 = 9.1 days) and Mo (LT50 = 8.9 days) were shorter than short-spored isolates Ma (LT50) = 10.0 days) and Ml (LT50 = 14.0 days). The mortality rates (regression slopes) showed that isolate Bp (5.32) killed Oryctes larvae slightly faster than isolate Mo (5.17); therefore, isolate Bp was selected for a field experiment.

A field trial was conducted in seven-month-old heaps of chipped oil palm trunks, using a single application of wet and dry inoculum. Using wet inoculum, each plot was drenched separately with 10 litres plot-1 of water containing 108, 109 and 1010 conidia. For dry inoculum, the plots were broadcasted with inoculated maize at 3 and 6 kg plot-1. In the field, Metarhizium infects adults, pupae and all larval stages of Oryctes beetles. At three months after treatment, pooled mortality for all stages of Oryctes beetles at the highest application rate was between 37% (dry inoculum) and 51% (wet inoculum). A great impact of Metarhizium was found only on third instar larvae, where it was able to reduce the number to about 5.5-5.8 larvae / sampling plot. This was significantly lower than the control which had 34.8 larvae / sampling plot.

The densities of viable spores in plots treated with wet inoculum at 1010 conidia (158.6 cfu) and dry at 6 kg (169.0 cfu) inoculum were significantly higher than the other application rates, especially at 3-month of treatment. A higher density of viable spores in breeding materials enhanced the disease development and subsequently reduced the beetle population. Wet inoculum had more advantages over dry inoculum had more advantages over dry inoculum. It was easily prepared using water from readily available sources such as field drains, river and extin mining pools. This study showed that wet inoculum was effective for control of Oryctes beetle and was more economical to apply than dry inoculum.  

EFFECT  OF GLUCOSE CONCENTRATION ON THE FORMATION OF TERMINAL INFLORESCENCES AND RIGID SHOOTS IN OIL PALM CULTURES.

Tarmizi, A H.

Oil palm cultures respond to external factors such as high osmoticum. It was observed that a high concentration of glucose (0.55 M to 0.82 M or 10% to 15% w / v) induced terminal inflorescences (TI) and rigidity in vitro shoots. The occurrence of TI  and rigid shoots varied from clone to clone. TI and rigid shoots also differed in their morphology within the same flask . This indicated that cultures responded differently in their development to glucose treatment. Thus, sensitivity of the cultures to high concentrations of glucose has potential to be used as a  technique for in vitro indexing of the stability of oil palm clonal materials.

INTERACTIONS BETWEEN MALAYSIAN AND INDONESIAN PALM OIL INDUSTRIES: SIMULATING THE IMPACT OF LIBERALIZATION OF IMPORTS OF CPO FROM INDONESIA.

Mohammad, H A; Mohd Fauzi, M J And Ramli, A

The presence of excess refining capacity in the refining sub-sector of the Malaysian palm oil industry is one of the challenges facing the industry. Market driven adjustments within the refining sub-sector that have taken place in the last few years (e.g. cessation of refining operations) have incurred significant costs to the industry. These costs would have been avoided if greater supply of crude palm oil (CPO) were made available either through increase in domestic production or imports. However, expansion of domestic production of CPO has been constrained by land and labour shortage. This paper investigates the impact on the industry from the liberalization of imports of CPO from Indonesia. A structural econometric model of the Malaysian palm oil industry will be used to simulate the effect of import liberalization. It is argued that import liberalization not only improves capacity utilization within the refining sub-sector, but also that the higher supply of CPO would help sustain the development of domestic downstream activities in the long run. As palm oil has been identified by the Industrial Master Plan (1985) as one of the resource-based industries to be developed, the simulation results would be useful to palm oil producers, policy makers and investors. However, import liberalization would require a more liberal trading stance to be adopted by both countries. As such, collaborative efforts would be beneficial to both sides given the fact that the market for fats and oils is a growing market.

METHOD FOR THE DETERMINATION OF PARAQUAT RESIDUE IN OIL MATRIX.

Kuntom, A; Kifli, H And Tan, Y A

Two experiments were carried out using the method developed by Imperial Chemical Industry (ICI) to determine paraquat residue in grains and crops. The aim of these experiments was to evaluate the feasibility of the method in determining paraquat residue in palm oil and palm oil products. Paraquat free RBD palm olein was used in the study. The method involved three steps: extraction of residue from the oil, clean up procedure using two types of equivalent resin, Duolite and Amberlite, spectrophotometric determintion of the purified material. In Experiment I, in which the resin Duolite was used, the percentage recoveries were adequate ranging from 50%-83%. The percentage recoveries increased with increasing concentration of paraquat. The  estimated limit of detection based on recovery data of this experiment was 0.01 ?g g^-1. In experiment II, using Amberlite, the percentage recoveries were greater than 90% for both the 0.05 ?g ml^-1 and 0.50 ?g ml^-1 level of concentration. Results from the two experiments showed that the ICI method can be applied for determination of paraquat residue in palm oil and palm oil products, and that the method with the use of Amberlite resin in the clean up step can give better recoveries of the analyte.

QUANTIFICATION OF OIL PALM BIOMASS AND NUTRIENT VALUE IN A MATURE PLANTATION.
II. BELOW-GROUND BIOMASS

Khalid, H; Zin, Z Z And Anderson, J M

The below-ground biomass of oil palm in a mature plantation was sampled and its nutrient contents and values estimated. Root biomass in this study was quantified by using core sampling and excavation method. The estimated root biomass amounted to about 16 t ha^-1 and the below-ground portions of trunk contributed little to the nutrient content of the stand. The total nutrient stocks from root biomass projected on per hectare basis were 65 kg N, 8 kg P, 128 kg K, 15 kg Mg and 12 kg Ca, in terms of monetary value worth about RM 278 ha^-1. The results show that oil palm roots provide significant amounts of nutrient which can be recycled in the plantation ecosystem at replanting.

MINERALIZATION OF SOIL ORGANIC CARBON AND NITROGEN IN RELATION TO RESIDUE MANAGEMENT FOLLOWING REPLANTING OF AN OIL PALM PLANTATION.

Khalid, H; Zin, Z Z And Anderson, J M

During oil palm replanting, substantial amounts of the above-ground oil palm residues were available which contributed about 577 kg N ha-1 and 40 t C ha-1 and the root materials produced about 65 kg N ha-1 and 8 t C ha-1. These materials were the main sources of C and N which would affect the mineralization of C and N in the soil. In this study, the potential mineralizable of N, the mineralization of organic C through soil respiration and CO2 evolution with different residues management practices were estimated.

 The results of C mineralization study showed that the carbon fluxes due to crop residues inputs contributed about 7.7 t CO2  ha-1 yr-1 which was mineralized from the soil. However, the mineralization rate of C from the light fraction organic matter which accumulated on the top soil surface was found to be about 20 times higher than that in the soil under the organic layer. The CO2  fluxes might largely reflect microbial activity from different residue treatments.

Nitrogen mineralization due to the inputs of crop residues could significantly increase the availability  of N to the young palms of which about 421 kg N ha-1 yr-1   were mineralized from the mineral soil and made available to the palms. In contrast, the N mineralization from the plot without crop residue inputs only contributed about 312 kg N ha-1 yr-1  which probably came from decomposed roots of the previous crop. Thus, the fluxes of about 109 kg N ha-1 yr-1  was transferred to the soil as a consequence of leaving crop residue about the ground during replanting of the plantation. A large amount of N was in the labile pool of the light fraction organic matter which accumulated on the top soil surface and which, when mineralized, was six to seven times higher than that in the soil under the organic layer.
 

DETERMINATION OF CHLORPHYRIFOS IN REFINED PALM OLEIN BY GC-FPD AND GC-ECD.

Halimah, M; Osman, H; Ainie, K; Tan, Y A And M D Pauzi, A

Chlorpyrifos (a pesticide containing phosphorous and chlorine) from oil matrix was determined using gas chromatography (GC) with a flame photometric (FPD) and electron capture (ECD) detectors. In the first experiment, the detector (FPD) used gave recoveries (from palm olein samples spiked with chlorpyrifos at levels of 0.04-0.10 ?g ml-1) ranging from 89% to 100% with coefficients of variation from 2.9% to 10.8%. In the second experiment, ECD showed recoveries (from palm olein spiked with chlorpyrifos at levels 0.02-0.10  ?g ml-1) of greater than 97% with coefficients of variations ranging from 0.5% to 2%. The results showed that using GC, the ECD and FPD are suitable detectors for quantification of chlorpyrifos in oil matrix.

THE OIL PALM TRUNK AS A CARBOHYDRATE RESERVE.

Henson, I E; Chang, K C; Siti Nor Aishah, M; Chai, S H; Hasnuddin Mhd, Y And Zakaria, A

Samples of oil palm trunk tissues were analysed for their contents of soluble sugar (SS), starch and acid-hydrolysable polysaccharides (PS). Starch was found in high concentrations only in samples taken near to the trunk apex of young palms, while SS and PS were present in appreciable amounts throughout the trunk.

The total amounts of carbohydrates present in the trunk of an eight-year-old palm were calculated as being sufficient to sustain the production of up to 38 kg of FFB.

Chromatographic and enzymatic analysis of the carbohydrates showed that sucrose was the main form of SS, followed in descending order by glucose and fructose. Acid hydrolysis of the polysaccharide fraction released mainly glucose together with appreciable proportions of a material with the chromatographic properties of xylose, together with some fructose.

Three trials were conducted to monitor variation in trunk carbohydrates in relation to bunch load, genotype and time of year. In the first trial, trunk carbohydrates levels were  compared in selected low and high yielding tenera palms. High yielding palms had higher SS levels, lower PS levels and a higher proportion of carbohydrate in the form of SS (%S) than low yielding ones. In the second trial, trunk carbohydrate were measured in 20 mature commercial teneras over a period of more than two years. Mean PS levels were again negatively correlated with bunch yield while %S was positively correlated with yield. The third trial made use of infertile pisiferas, and tenera sibling  progenies
from the breeding population. Tenere palms had lower PS levels and more of the trunk carbohydrates present in the form of SS than did pisiferas. Infertile pisiferas had higher PS levels and a lower proportion of SS than did fertile pisiferas.

The results are discussed in relation to the possible role of trunk carbohydrates as a source of assimilates during periods of peak bunch production.

REACTION FORCE AND ENERGY REQUIREMENT FOR CUTTING OIL PALM FRONDS BY SPRING  POWERED SICKLE CUTTER.

Abdul Razak Jelani; Desa Ahmad; Ahmad Hitam; Azmi Yahya And Johari Jamak

A Study was conducted to investigate the effect of  cutting angle and from maturity  on the specific reaction force (ROCSA) and energy requirement (RENCSA) for cutting oil palm fronds. A spring powered sickle cutter was used in the experiment. The experiment conducted was to determine the magnitude of reaction force that would be transferred to the harvester in the cutting operation. Cutting angles of 90o, 60o, and 45o were tested on the three levels of frond maturity (F1, F2 and F3).

Experiment carried out showed significant effects of cutting angle on the ROCSA and RENCSA but not by frond maturity. Increasing the cutting angle from 45o to 90o  increased the ROCSA to  about 72%. The maximum and minimum values of ROCSA were 24.5 N cm-2   and 10.8 N cm-2  respectively.

The ratio of reaction force to the maximum cutting force (R/Fcmax) was also studied. The ratio gives the percentage of cutting force being transferred to the harvester during the cutting process. It was found that R/Fcmax was significantly affected by the cutting angle and frond maturity. The maximum and minimum ratios were 35% and 14% at cutting angles of  70o and 45o  for cutting F3 a d F1, respectively.

VOLUME  11 NO.1 - June 1999

PHYSICAL AND CHEMICAL PROPERTIES OF SHORTENINGS FROM PALM OIL:TALLOW AND PALM OLEIN:TALLOW BLENDS WITH AND WITHOUT INTERESTERIFICATION.

Osman A And Nor Aini I

Palm oil and palm olein were blended with tallow at level of 80%, 70% and 60%. Part of the blends was interesterified. Blends and interesterified blends were processed into shortenings. These shortenings and a commercial shortening as control were evaluated for their solid fat content (SFC) and slip melting points (SMP), fatty acid (FA) and triglycerides (TG) composition, and creaming and baking properties. The slip melting points of the interesterified shortenings for palm oil:tallow and palm olein:tallow blends were higher than those of non-interesterified, but lower than the commercial shortening. The two most abundant fatty acids present in both blends were palmitic and stearic. The shortenings were rich in C52 and C50 glycerides. Interesterification process increased the solid fat content of the blends, except in 60:40 palm olein:tallow. Creaming power after 12 minutes of beating improved in the interesterified palm olein:tallow blends. However, creaming properties of the interesterified palm oil:tallow blends were poorest among the shortenings. Baking performance of non-interesterified palm oil:tallow blends was better than interesterified group.

AN ACCURATE AND PRECISE METHOD OF DETERMINING OIL TO BUNCH IN OIL PALM.

Chan K S, Soh A C And Chew P S

This paper  describes  a simple oil balance method for the  determination  of oil to bunch (O/B) and kernel to bunch (K/B) whereby the tedious manual process of removing the mesocarp eliminated by cutting the fruit longitudinally into two halves. After drying and removing the dried kernels, the dry mesocarp and shell are reduced into fine particles using an electric grinder which also homogenize the sample leading to greater accuracy in oil determination. Comparison of this method with the routine Blaak’s bunch analysis method showed that Blaak’s method gave O/B results which were higher than those of the oil balance method by an average of 15% of the mean O/B. On the other hand, the O/B and K/B figures obtained by the oil balance method agreed closely with the mill oil and kernel extraction rates after taking into account harvesting and processing losses.

Linear regression analysis showed that O/B decreased as bunch weight increased mainly due to a decreasing oil content of the fruits.

The results of a sampling exercise verified that the oil balance method was accurate with the estimates differing from the true values by about 1% unit for O/B and 2% units for K/B. Greater precision was obtained with fruit samples taken from all the fruits which  had been stripped from the spikelets after three days compared to fruits from intact spikelet samples taken on the first day. After quantification of the coefficients of variation (CV) of the bunch component ratios, the  CVs or precisions of estimating O/B and K/B using different sampling systems were computed.

QUANTIFICATION OF OIL PALM BIOMASS AND NUTRIENT VALUE IN A MATURE PLANTATION. I. ABOVE-GROUND BIOMASS.

Khalid H, Zin Z Z And Anderson J M

Oil palm biomass in a mature plantation was quantified and the availability of its nutrient contents and values was estimated. In the present study, the nutrient stocks of above-ground standing oil palm biomass and the contribution of each palm component were quantified and measured directly in order to obtain more precise values. The total above-ground biomass amounted to about 85t ha-1 and the trunk contributed the major portion to about 48% of oil palm standing biomass. The  total nutrient stocks of above ground biomass produced at felling of old stands based on per hectare basis are 577kg N, 50 kg P, 1255 kg K, 141kg Mg and 285kg Ca which could be recycled in the plantation both as organic matter and savings in monetary value worth about RM 2550 ha-1. Removal of this biomass for other value-added products has implications for plantation management in terms of losses of nutrients and organic matter to maintain soil fertility. Appropriate management of this biomass could enable its carry-over of nutrients necessary to support the growth of the following rotation of crop.

NOTES ON OIL PALM PRODUCTIVITY. IV. CARBON DIOXIDE GRADIENTS AND FLUXES AND EVAPOTRANSPIRATION, ABOVE AND BELOW THE CANOPY.

Henson I E

Continuous measurements of atmospheric CO2 concentrations made at various heights within and above a mature oil palm canopy showed that concentrations varied widely during the course of a 24-hour period - building up to high levels overnight within the canopy and falling rapidly with the onset of photosynthesis in the morning. Measurement of CO2 fluxes, both within the atmospheric boundary layer above the canopy and within the trunk space, allowed the relative contribution of CO2 supplied from the above and below-canopy atmosphere to the total canopy CO2 assimilation to be assessed. Similar assessment of water vapour fluxes provided a measure of the percentage of water lost as evapotranspiration (ET) which was channelled through the palms. Below-canopy CO2 uptake averaged 18.5% of the above-canopy flux and 15.6% to total flux. Evapotranspiration from the ground (from soil and ground flora) was almost 13% of total evapotranspiration, so that over 87% of ET took place directly from the palm canopy.

NOTES ON OIL PALM PRODUCTIVITY. V. EVALUATION OF ALTERNATIVE MECHANISMS FOR SUPPORTING SEASONAL VARIATION IN DRY MATTER PRODUCTION.

Henson I E

Three alternative mechanisms leading to seasonal variations in bunch and total dry matter production commonly found in stands of oil palm, were examined using a simulation model. The alternatives were: (i) the use of a store of reserve assimilate to accommodate both shortfalls and excesses in current assimilate production, (ii) variation in response to sink demand in the light-saturated rate of gross photosynthesis (AMAX), and (iii) variation in the proportion of gross assimilates consumed in dark respiration (%R). The alternatives were tested using data from three palm populations for one of which, trunk carbohydrate concentrations had also been measured.

The results show that with certain assumptions, any of these processes could account for the seasonal variations in productivity recorded. However, certain periods of relatively high or low productivity required extreme variations in AMAX, which were considered unlikely. The variations in %R which were needed were also thought unlikely as periods of high productivity required %R to decrease, whereas the opposite trend was more probable. Thus, of the three processes, the utilization of storage reserves appeared the most likely means of accommodating variations in sink demand. However, a model based solely on use of assimilate storage was not entirely consistent with measured changes in trunk reserves and changes in AMAX and / or use of reserves, located in other parts of the palm may be involved.

 Further research needed to resolve this issue is suggested.

MONO- AND DIBASIC ACIDS FROM LIQUID PHASE OXIDATION OF PALM OIL PRODUCTS.

Ooi T L, Mizukami F And Niwa S

The main objective of the research was to convert palm oil products into basic intermediates for use in the chemical industry. In this paper, oxidative cleavage of palm oil products into dibasic acids and low molecular weight monobasic acids by liquid phase oxidation of palm oil products in discussed. Identification of reaction products was done with gas chromatography and gas chromatography/mass spectroscopic techniques and it was found that the major dibasic acids formed in the reaction were suberic and azelaic acids. The dibasic acids produced were concentrated by water washing followed by crystallization. The maximum purity of azelaic acid achieved was 78% .The dibasic acids are useful materials for the syntheses of lubricants, plasticizers, polyamides and polyesters.

OXIDATION AND THERMAL DEGRADATION OF CAROTENOIDS.

Bonnie T Y P And Choo Y M

Carotenoids are widely used in food applications. Their highly unsaturated nature makes them susceptible to degradation by oxidation and thermal processes, especially under severe processing and storage conditions. The mechanisms during auto-, photo-catalyzed and photosensitized-oxidations of trans ?-carotene are discussed. The oxidation products formed are mixture of epoxides, apocarotenal and hydroxy compounds. Isomerization, oxidation and breakdown of the carotenoid molecule occur as a result of thermal degradation. Two types of thermal degradation products are formed: volatile and non-volatile. The volatile fraction consists of low molecular weight molecules which vapourizes. The non-volatile fraction is the residual fraction after vapourization of the volatile fraction. The mechanisms for formation of the two fractions are discussed.

EFFECTS OF WEATHER ON YIELD COMPONENTS OF THE OIL PALM IN A FOREST LOCATION IN NIGERIA.

Oboh B O And Fakorede M A B

Simple linear correlations, stepwise multiple regressions and path coefficient analysis were used to determine the relationship between climatic variables and yield components in the oil palm; i.e. number of bunches (NB), fresh fruit bunch yield (FFB) and mean bunch weight (MBW) over a  13-and 20-year period. Yield could be reliably predicted from minimum relative humidity and sunshine hours 18-24 months prior to harvest.