Kuala Selangor, Malaysia
Kuala Selangor, Malaysia

Time filter

Source Type

Goh Y.K.,Advanced Agriecological Research Sdn Bhd | Marzuki N.F.,Advanced Agriecological Research Sdn Bhd | Goh T.K.,Advanced Agriecological Research Sdn Bhd | Tan S.Y.,Advanced Agriecological Research Sdn Bhd | Goh K.J.,Advanced Agriecological Research Sdn Bhd
Biocontrol Science and Technology | Year: 2016

The objective of this study was to assess the interactions between Scytalidium parasiticum (Sp) and Ganoderma boninense, the causal agent of basal stem rot (BSR) in oil palm (Elaeis guineensis). When compared with Scytalidium ganodermophthorum and Scytalidium sphaerosporum, Sp showed greater inhibition towards all Ganoderma isolates during dual-culture assays. At the interaction zone, coiling of host hyphae, formation of short lateral enlarged contact structures, and production of appressorium-like organs organs were observed in Sp on G. boninense. These were followed by the degradation, shrinkage, and deformation of G. boninense mycelia. Sp reduced mycelial survival and fruiting body regeneration of G. boninense. Sp's non-volatile metabolites suppressed the growth of G. boninense. Our results show that Sp could be a necrotrophic mycoparasite of G. boninense. Nursery experiments revealed that Sp was non-pathogenic to oil palm seedlings, and it could suppress Ganoderma infection and reduce disease severity. Sp increased the height of palms in the positive control with non-Ganoderma-inoculated rubber wood block and Sp inoculum compared to similar control without Sp. Leaf area was greater in the G. boninense G8 inoculated palms when Sp was present compared to without Sp. These results show that Sp might be a potential biocontrol candidate against BSR. © 2016 Advanced Agriecological Research Sdn Bhd.


Ooi S.-E.,Malaysian Palm Oil Board | Choo C.-N.,Advanced Agriecological Research Sdn Bhd | Zamzuri I.,Malaysian Palm Oil Board | Ong-Abdullah M.,Malaysian Palm Oil Board
Journal of Oil Palm Research | Year: 2013

The in vitro propagation of the oil palm involves an indirect somatic embryogenesis process through an intervening callogenesis phase. Both processes are determining factors in the success of clonal propagation. This study aims to discover expression markers associated with hormone response as a means to measure the favourable response of oil palms to callogenesis. Expression levels of hormone responsive genes in cultured and uncultured leaf explants were measured by using quantitative real time PCR, followed by statistical analysis to determine whether a relationship to callogenesis existed. The potential for callogenesis in cultured leaf explants of oil palms was significantly correlated to the expression changes of a putative brassinosteroid leucine-rich repeat (LRR) receptor kinase (EgBrRK), a putative cytokinin dehydrogenase (EgCKX) and a putative response regulator type A gene (EgRR1). A regression model for callogenesis incorporating these three genes indicated a predicted R2 value of 67.89%. The larger reduction in the expression of EgRR1 and another cytokinin responsive gene, EgCK REGULATED KINASE, in cultures exhibiting higher callogenesis rates suggested an increase in cytokinin signaling output and cytokinin levels. This inference was supported by a slight decrease in the expression of EgCKX, suggesting a mild reduction in cytokinin degradation in these cultures. The use of these markers for the prediction of callogenesis rate in uncultured and one-day cultured leaf explants, may provide an early assessment of the callogenesis potential of oil palms.


Ping L.Y.,University Putra Malaysia | Boon Sung C.T.,University Putra Malaysia | Joo G.K.,Advanced Agriecological Research Sdn Bhd | Moradi A.,University Putra Malaysia
Malaysian Journal of Soil Science | Year: 2012

In order to reduce soil erosion on sloping lands, empty fruit bunches (EFB), Ecomat, oil palm frond heaps, or silt pit have been used by major oil palm plantations. Studies have shown that at 0-15 cm soil depth, organic matter content in EFB is highest among the four treatments. Besides, EFB had the highest humic acid content compared to the others, about two times higher than control. Our analysis showed that aggregate stability of EFB was the highest among four treatments at 54.88%, followed by Ecomat (47.7%), silt pit (44.76%) and finally, control (42.12%). We observed that organic matter content inversely correlated with Fe (p < 0.05) and Al (p < 0.05) oxides. Finally, yield of humic acids correlated with soil pH (p < 0.05), aggregate stability (p < 0.01) and aggregate size distribution (p < 0.01). Among the four treatments, application of EFB as a mulching material commonly practised in oil palm estates was found to be the best practice on sloping lands due to its high organic matter and humic substances content that retain soil particles by improving soil aggregate stability and aggregation.


Ooi S.-E.,Malaysian Palm Oil Board | Choo C.-N.,Advanced Agriecological Research Sdn Bhd | Ishak Z.,Malaysian Palm Oil Board | Ong-Abdullah M.,Malaysian Palm Oil Board
Plant Cell, Tissue and Organ Culture | Year: 2012

This study correlates the potential for somatic embryogenesis in cultured leaf explants of oil palm trees with changes in the expression of hormone-responsive genes. The results show that expression of the putative Aux/IAA gene EgIAA9 is specifically correlated to somatic embryogenesis. A regression model for embryogenesis indicated a predictive R 2 value of 63.55 % for this expression marker. Auxin is the plant growth regulator used for induction during the early stages of oil palm tissue culture. Expression of EgIAA9 decreased in response to increasing concentrations of exogenous 2,4-D. EgIAA9 expression profiles in cultured leaf explants from highly embryogenic palms, in embryogenic and non-embryogenic calli, and in response to increasing exogenous 2,4-D, suggested that endogenous auxin levels may be greater in highly embryogenic palms. The use of this marker to predict embryogenesis in oil palm tissue culture prior to the visible onset of this event is promising. Moreover, the results of this study prompt further investigations into the role of Aux/IAA genes in oil palm somatic embryogenesis. © 2012 Springer Science+Business Media B.V.


Hoang K.P.,Vietnam National University, Hanoi | Teo T.M.,Advanced Agriecological Research Sdn Bhd | Ho T.X.,University of Arkansas | Le V.S.,Vietnam National University, Hanoi
Parasites and Vectors | Year: 2016

Background: More effective mosquito control strategies are urgently required due to the increasing prevalence of insecticide resistance. The sterile insect technique (SIT) and the release of insects carrying a dominant lethal allele (RIDL) are two proposed methods for environmentally-friendly, species-targeted population control. These methods may be more suitable for developing countries if producers reduce the cost of rearing insects. The cost of control programs could be reduced by producing all-male mosquito populations to circumvent the isolation of females before release without reducing male mating competitiveness caused by transgenes. Results: An RNAi construct targeting the RNA recognition motif of the Aedes aegypti transformer-2 (tra-2) gene does not trigger female-to-male sex conversion as commonly observed among dipterous insects. Instead, homozygous insects show greater mortality among m-chromosome-bearing sperm and mm zygotes, yielding up to 100 males in the subsequent generations. The performance of transgenic males was not significantly different to wild-type males in narrow-cage competitive mating experiments. Conclusion: Our data provide preliminary evidence that the knockdown of Ae. aegypti tra-2 gene expression causes segregation distortion acting at the level of gametic function, which is reinforced by sex-specific zygotic lethality. This finding could promote the development of new synthetic sex distorter systems for the production of genetic sexing mosquito strains. © 2016 Hoang et al.


Kimura S.D.,Tokyo University of Agriculture and Technology | Melling L.,Tropical Peat Research Laboratory Unit | Goh K.J.,Advanced Agriecological Research Sdn Bhd
Geoderma | Year: 2012

The influence of oil palm development on tropical peat soil decomposition rate was investigated by an incubation experiment. Soil samples from soil surface and around underground water table were taken from forest site, and oil palm site at 1st and 9th year after development. The soil samples were sieved into 0-2mm, 2-8mm and 8-20mm and analyzed for carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes.The development of oil palm did not change the CO2 emissions and showed inconsistent influence on CH4 flux according to aggregate size, while significantly higher N2O emissions were found for aggregates 0-2mm at high moisture of oil palm plantation soils compared with the original forest. Nitrous oxide fluxes showed significant positive correlation with the CO2 flux, which indicated that soil organic matter decomposition was closely related to the N2O production. On the other hand, CH4 flux showed clear emission for aggregates bigger than 2mm, while aggregates size 0-2mm showed consistent CH4 uptake. These results showed that investigation of greenhouse gas emissions in tropical peat soil must take into account the aggregate characteristics of the soil, which are inhomogeneous and mixed with fresh organic matter. © 2012 Elsevier B.V.


Melling L.,Tropical Peat Research Laboratory Unit | Chaddy A.,Tropical Peat Research Laboratory Unit | Goh K.J.,Advanced Agriecological Research Sdn Bhd | Hatano R.,Hokkaido University
Acta Horticulturae | Year: 2013

The large store of organic matter in tropical peatland undergoes natural decomposition and respiration processes to produce soil carbon dioxide (CO 2). The conversion of tropical peatland into oil palm plantation has been assumed to enhance the decomposition process due to drainage, causing further emission of soil CO2. It is postulated that this process will increase with time of oil palm cultivation. Hence, the objective of this study was to determine the influence of environmental variables and root biomass on soil CO2 fluxes from different ages of oil palm. Thesoil CO 2 fluxes were measured for 24 months from three palm ages (1, 5 and 7 years of planting; S1, S2, S3) in tropical peatland of Sarawak, Malaysia using a closed-chamber technique. The highest mean soil CO2 flux was recorded in S3 (221.26 mg C m-2 h-1) followed by S2 (195.43 mg C m-2 h-1) and S1 (177.63 mg C m-2 h-1) palms. The cumulative soil CO2 fluxes for S1, S2 and S3 were 14.72, 16.38 and 18.53 t C ha-1 yr-1, respectively. Water-filled pores space (WFPS) correlated negatively with soil CO2 fluxes in all of the three different ages of oil palm probably due to reduced root respiration. The increase in soil CO2 flux with palm age was consistent with higher root biomass of growing palms suggesting that root respiration was a major component of soil respiration in tropical peatland under oil palm.


Chee W.W.,Advanced Agriecological Research Sdn Bhd | Jit T.C.,Advanced Agriecological Research Sdn Bhd | Kien W.C.,Advanced Agriecological Research Sdn Bhd | Mayes S.,University of Nottingham Malaysia Campus | And 2 more authors.
Journal of Oil Palm Research | Year: 2015

DNA fingerprints provide the basis for genetic diversity studies and molecular breeding. However, routine and commercial scale DNA fingerprinting in oil palm (Elaeis guineensis Jacq.) remains challenged by the need for a robust yet low cost method. In addition, there is also a need for a precise and reliable marker set capable of distinguishing oil palm genotypes within narrow and mixed genetic population bases at the individual and population level. With the rapid evolution of genotyping and sequencing technologies, a wide range of genotyping tools have been developed but are not yet commercially feasible for oil palm. Consequently, we tested the feasibility of using simple sequence repeat (SSR) markers to genotype oil palm breeding and commercial planting materials of restricted and mixed parentage from Advanced Agriecological Research Sdn Bhd (AAR). The results obtained from screening 33 palms using a selected set of 17 highly polymorphic and informative SSR markers obtained from an initial set of 23 SSR, showed that clones, crosses and sibs within crosses could be separated by their DNA fingerprints. However, as expected palms within clones could not be separated. In another test exercise at the population scale, the four variable but related populations: Deli; Dumpy Deli x Yangambi x AVROS; Dumpy Deli x AVROS; Dumpy Deli x AVROS x La Me; were distinctly separated using 11 SSR from the same pool of 23 polymorphic SSR. There is good potential for this set of 11 SSR markers to be developed for general applicability across all E. guineensis oil palm genetic materials and for use in the Malaysian Plant Variety Protection Act. The set of SSR markers also serve as the base set for the development of marker-assisted and genome-wide selection at AAR.


Goh Y.K.,Advanced Agriecological Research Sdn Bhd | Goh T.K.,Quest International University Perak | Marzuki N.F.,Advanced Agriecological Research Sdn Bhd | Tung H.J.,University of Nottingham Malaysia Campus | Goh K.J.,Advanced Agriecological Research Sdn Bhd
Mycobiology | Year: 2015

A mycoparasite, Scytalidium parasiticum sp. nov., isolated from the basidiomata of Ganoderma boninense causing basal stem rot of oil palm in Johor, Malaysia, is described and illustrated. It is distinct from other Scytalidium species in having smaller asci and ascospores (teleomorphic stage), longer arthroconidia (anamorphic stage), hyaline to yellowish chlamydospores, and producing a fluorescent pigment. The phylogenetic position of S. parasiticum was determined by sequence analyses of the internal transcribed spacers and the small-subunit ribosomal RNA gene regions. A key to identify Scytalidium species with teleomorphic stage is provided. © 2015 The Korean Society of Mycology.


PubMed | Vietnam National University, Hanoi, University of Arkansas and Advanced Agriecological Research Sdn Bhd
Type: | Journal: Parasites & vectors | Year: 2016

More effective mosquito control strategies are urgently required due to the increasing prevalence of insecticide resistance. The sterile insect technique (SIT) and the release of insects carrying a dominant lethal allele (RIDL) are two proposed methods for environmentally-friendly, species-targeted population control. These methods may be more suitable for developing countries if producers reduce the cost of rearing insects. The cost of control programs could be reduced by producing all-male mosquito populations to circumvent the isolation of females before release without reducing male mating competitiveness caused by transgenes.An RNAi construct targeting the RNA recognition motif of the Aedes aegypti transformer-2 (tra-2) gene does not trigger female-to-male sex conversion as commonly observed among dipterous insects. Instead, homozygous insects show greater mortality among m-chromosome-bearing sperm and mm zygotes, yielding up to 100% males in the subsequent generations. The performance of transgenic males was not significantly different to wild-type males in narrow-cage competitive mating experiments.Our data provide preliminary evidence that the knockdown of Ae. aegypti tra-2 gene expression causes segregation distortion acting at the level of gametic function, which is reinforced by sex-specific zygotic lethality. This finding could promote the development of new synthetic sex distorter systems for the production of genetic sexing mosquito strains.

Loading Advanced Agriecological Research Sdn Bhd collaborators
Loading Advanced Agriecological Research Sdn Bhd collaborators