Category Archives: In Press

DEVELOPMENT AND FIELD EVALUATION OF A TRACTOR MOUNTED OIL PALM TRUNK INJECTOR

This article describes the design, development and testing of a trunk injection machine. The machine comprised of an injection apparatus, hydraulic system and 200-litre storage tank mounted on a mini-tractor. Experiments were conducted to test injection effectiveness test, time and motion study (TMS) and field trial. The injection effectiveness test using 0.1% eosin dye on the healthy palms revealed that the machine was able to spread the dye to more than 60% coverage on the vertical (X) and horizontal (Y) axes, and up to 65 cm upwards on the longitudinal axis (Z). Results recommended to have two injections per palm for a better coverage profile. TMS revealed that the machine was able to treat about 37 palms per day with the injection cost of about RM 3.15 per palm. Study on 2088 Ganoderma-infected palms in an estate showed that 95.6% of the infected palms were still standing after one year treatment with Hexaconazole. The cost-effectiveness was calculated at RM 1.02 per palm over five-year of economic life. With the performance and cost of the machine, it is recommended that this machine is suitable to be used to treat palms infected with basal stem rot disease (BSR).

BREEDING FOR DROUGHT TOLERANCE IN OIL PALM

As the oil palm industry expands, drought tolerance will become increasingly important. In the breeding programme of Univanich Palm Oil PCL in Southern Thailand, progeny trials are duplicated with and without irrigation. This allows drought tolerance of progenies to be estimated, in terms of the reduction in yield caused by withholding irrigation. Correlations between irrigated and unirrigated progeny mean yields are low, and some pairs of trials show significant progeny x irrigation interactions. Unirrigated yield is highly correlated with drought tolerance, but yield under irrigation tends to be negatively correlated with tolerance. Thus, selection in the absence of drought may produce material that is drought susceptible, and selection should be done under the conditions in which the material will be planted. We have not found a reliable indirect method for identifying drought tolerance, but the use of stomatal conductance as a selection criterion appears worth investigating further.

PROFILING OF ANTI-FUNGAL ACTIVITY OF Trichoderma virens 159C INVOLVED IN BIOCONTROL ASSAY OF Ganoderma boninense

Trichoderma has long been recognised as a potential biological control agent (BCA) against pathogenic fungi due to antagonistic characteristics and it has successfully controlled Ganoderma boninense at the nursery stage in previous study. This study attempts to identify the mechanisms involved in the suppression of G. boninense and the anti-fungal compounds released by endophytic Trichoderma virens 159c. Therefore, culture filtrates of endophytic T. virens 159c was extracted using hexane, ethyl acetate (EtOAc) and butanol (BuOH) and anti-fungal activity was tested. The EtOAc extract showed highest anti-fungal activity with percentage inhibition of radial growth (PIRG) of 78.39% ±5.40. The scanning electron microscope (SEM) showed severe deformation of G. boninense PER 71 mycelia observed at the inhibition region caused by EtOAc extract. Further fractionated with column chromatography and antifungal assay revealed that fractions 2 and 4 had highest anti-fungal activity. Analysis carried out using gas chromatography-mass spectrometry detector of the active fraction allowed the identification of acetamide, alcohol, lactones and free fatty acids. Phenylethyl alcohol (PEA) was discovered as a unique compound because the presence was only in the highly inhibitory fraction of T. virens. In addition, dl-mevalonic acid lactone in fraction 4 of T. virens 159c was first reported in T. virens.

TISSUE-SPECIFIC PROMOTERS: THE IMPORTANCE AND POTENTIAL APPLICATION FOR GENETIC ENGINEERING IN OIL PALM

Oil palm is the most prolific oil crop in the world with a productive life span of 20-30 years and this perenniality bestows significant advantages over other oil crops. However, the industry still faces a number of challenges and to ensure its future sustainability, efforts must be made to diversify applications to increase its economic value. Amongst potential strategies include the use of genetic engineering approaches to fulfil the needs. To ensure that expression of transgenes for the production of genetically engineered products is directed to targeted tissue(s), promoter sequences that are responsible to direct the expression of desired genes have been identified. In this review we discuss the isolation and characterisation of oil palm tissue-specific promoters from mesocarp and kernel, an inducible tissue-specific promoter from roots, and the utility of constitutive promoters. The tissue-specific and constitutive functions of these promoters were confirmed through transient expression studies in oil palm and some of the isolated promoters were further characterised using Arabidopsis as a model system. We hope that these promoters can potentially be utilised to improve oil yield and quality, to fine tune the agronomic traits, and to generate high value-added products for the oil palm.