Kevin Kit Siong Ng

Forest Research Institute Malaysia (FRIM) | frim · Genetic Laboratory

Forests help to reduce global warming by capturing and storing atmospheric carbon. Understanding the genetics of keystone species at a population level is vital for the management and sustainable utilization of forest genetic resources. A comprehensive population genetics study was carried out on Rubroshorea curtisii, an important widespread hill d...

Unlabelled: With the rapid growth of the fruit industry worldwide, it is important to assess adulteration to ensure the authenticity and the safety of fruit products. The DNA barcoding approach offers a quick and accurate way of identifying and authenticating species. In this study, we developed reference DNA barcodes (rbcL, ITS2, and trnH-psbA) f...

Mitragyna speciosa or locally known as ketum is a medicinal plant native to Southeast Asia including Malaysia. It has been used in traditional medicine to treat various illnesses. Given its psychoactive properties and potential abuse, the cultivation of the plant is restricted to research purposes in Malaysia. There is little information on the ins...

In the context of forensic forestry, the unique properties of DNA within a timber could be used to support the determination of origin and identity. The Forest Research Institute Malaysia (FRIM) was an old mining land in the past century, but it was successfully restored as a man-made forest since 1920s. As the origin of the planted species was mos...

Many tree planting programmes have long been initiated to increase forest cover to mitigate the effects of global climate change. Successful planting requires careful planning at the project level, including using suitable species with favourable traits. However, there is a paucity of improvement data for tropical tree species. An experimental comm...

International timber trade communities are increasingly demanding that timber in the wood supply chain be sourced from sustainably harvested forests and certified plantations. This is to combat illegal logging activities to prevent further depletion of our precious forests worldwide. Hence, timber tracking tools are important to support law enforce...

Shorea parvifolia (Dipterocarpaceae) is a widely distributed tree species which is important in terms of ecosystem functioning as well as forestry in Southeast Asia. During glacial periods, substantial precipitation decline is believed to have occurred in Southeast Asia, which considerably changed the distribution of the species. Repeated glacial a...

Aquilaria malaccensis (Thymelaeaceae) is the main source of high-grade agarwood in Southeast Asia. Aggressive collections and trade activities over the past decades have put great pressure on the natural stands and raised concerns over the long-term survival potential of A. malaccensis. Tracking and authentication of agarwood require method with a...

Hyperdiverse tropical rainforests, such as the aseasonal forests in Southeast Asia, are supported by high annual rainfall. Its canopy is dominated by the species-rich tree family of Dipterocarpaceae (Asian dipterocarps), which has both ecological (e.g., supports flora and fauna) and economical (e.g., timber production) importance. Recent ecological...

Understanding internode elongation in woody species is the basis of stable timber production. Although trees exhibit coordinated growth between leaves and internodes, it is unclear whether their coordinated growth occurs simply because both organs receive a common signal that triggers their growth or because the growth of one organ is regulated by...

Baeckea frutescens or Cucur Atap, is a medicinal plant that has been traditionally used as herbal medicine and has great potential for pharmaceutical application due to its biological properties. The increasing demand for B. frutescens herbal medicinal products has led to its over-exploitation. Therefore, it is crucial to generate baseline genetic...

Abstract. Located at Bersia Timur, the Rafflesia Conservation and Interpretive Centre (RCIC) was initiated by the Forest Research Institute Malaysia (FRIM) and FELDA to boost research and conservation efforts of the iconic Rafflesia species in the state of Perak. It also plays a role in supporting the economy of local communities by promoting local...

Premise: Leaf phenology is an essential developmental process in trees and an important component in understanding climate change. However, little is known about the regulation of leaf phenology in tropical trees. Methods: To understand the regulation by temperature of leaf phenology in tropical trees, we performed daily observations of leaf pro...

Worldwide, many mangrove species are experiencing significant population declines, including Rhizophora apiculata, which is one of the most widespread and economically important species in tropical Asia. In Malaysia, there has been an alarming decline in R. apiculata populations driven primarily by anthropogenic activities. However, the lack of gen...

Our study highlights the utilization of a genetic database for wood-origin identification in Intsia palembanica, a valuable heavy hardwood from the tropical forests. This forensic tool is essential for strengthening the verification of legality in the wood supply chain from the forest to the end-users. An increasing number of rules and regulations...

Shorea platyclados (Dark Red Meranti) is a commercially important timber tree species in Southeast Asia. However, its stocks have dramatically declined due, inter alia, to excessive logging, insufficient natural regeneration and a slow recovery rate. Thus, there is a need to promote enrichment planting and develop effective technique to support its...

Shorea leprosula is highly demanded for its timber and a promising species for reforestation. a common garden experimental plot was established in FRIM as a germplasm bank to study the genetic basis of S. leprosula complex traits. Pest surveys carried out in the study plot between 2018-2020 recorded four species of defoliators, four species of sap-...

To inform product users about the origin of timber, the implementation of a traceability system is necessary for the forestry industry. In this study, we developed a comprehensive genetic database for the important tropical timber species Merbau, Intsia palembanica, to trace its geographic origin within peninsular Malaysia. A total of 1373 individu...

Southeast Asian rainforests at upper hill elevations are increasingly vulnerable to degradation because most lowland forest areas have been converted to different land uses. As such, understanding the genetics of upper hill species is becoming more crucial for their future management and conservation. Shoreaplatyclados is an important, widespread u...

Documenting the scale and intensity of fine-scale spatial genetic structure (FSGS), and the processes that shape it, is relevant to the sustainable management of genetic resources in timber tree species, particularly where logging or fragmentation might disrupt gene flow. In this study we assessed patterns of FSGS in three species of Dipterocarpace...

Topographic maps of the four research plots including the coordinates of sampled individuals (S1A–S1D Fig). (DOCX)

Microsatellite genotype data and spatial coordinates for all trees sampled from DVCA, together with P. tomentella data from SFR [4], S. leprosula from PFR [14], and S. parvifolia from LHNP [18]. (XLSX)

Demographic Elevation Model (DEM) of the SFR 50 ha plot. Requires opening as a raster file, using the WGS84 coordinate system, UTM zone 50. (TIF)

Primer details for all loci for the three dipterocarp species sampled at DVMA, together with P. tomentella data from SFR [4], S. leprosula from PFR [14], and S. parvifolia from LHNP [18]. (DOCX)

Sampling of Parashorea tomentella from the Sepilok Forest Reserve (SFR). (DOCX)

The development of timber tracking methods based on genetic markers can provide scientific evidence to verify the origin of timber products and fulfill the growing requirement for sustainable forestry practices. In this study, the origin of an important Dark Red Meranti wood, Shorea platyclados, was studied by using the combination of seven chlorop...

Graph of Delta K showing K = 2 as the most probable number of genetic clusters. (DOCX)

Allele frequencies for each of the 15 STR markers used to delimit the Malaysian Database of Shorea platyclados. Minimum allele frequencies were adjusted for alleles falling below the (5/2n = 0.0024) threshold. (DOCX)

Variable sites (base substitutions and indels) across the seven chloroplast intergenic regions (trnT-trnL, trnS-trnG, atpB-rbcL, petG-trnP, trnG-atpA, psbM-trnD and trnG-rps14) used to delimit the Shorea platyclados in the population identification database. (DOCX)

Seven chloroplast DNA primers pair used in the study. (DOCX)

The evaluations of Hardy-Weinberg equilibrium (HWE) and linkage equilibrium on the 15 STR loci of Shorea platyclados in each population. (DOCX)

Background: The impact of logging and restoration on species diversity has been well studied in tropical forests. However, little is known about their effects on genetic diversity within species. Aims: We assess the degree of genetic diversity among dipterocarp seedlings used for enrichment planting of selectively logged forests in Sabah, Malaysia,...

Background: Dipterocarpaceae is a pantropical tree family that plays an important role in our understanding of the ecology of Asian tropical rain forests. However, genome sizes for members of the Dipterocarpaceae are still poorly known. Aims: To report the genome size of 115 dipterocarp species and examine the variation and evolution of genome size...

Premise of the study: In tropical rainforests of Southeast Asia, a highly fecund thrips (Thrips spp.) responds rapidly to the mass flowering at multiple-year intervals characteristic of certain species such as the canopy tree studied here, Shorea acuminata, by feeding on flower resources. However, past DNA analyses of pollen adherent to thrips bod...

Variation in tree species floristic composition and local-scale distribution in tropical forests is thought to be associated with habitat. This study compared the spatial distribution pattern and spatial genetic structure of Shorea parvifolia spp. parvifolia in a lowland and a hill dipterocarp forest and postulated how the spatial structure of a tr...

Selective logging simulations and male fecundity variation support customisation of management regimes for specific groups of dipterocarp species in Peninsular Malaysia. Modelling based on paternity analysis of one hill and three lowland dipterocarp timber species in Malaysia indicated that more pollen donors sired progeny in Shorea leprosula and S...

Taxonomic classification of the important medicinal plant, _Ficus deltoidea_ (Moraceae), is challenging because of the variability of its leaves and fig forms that occur within the species. We developed 16 nuclear Simple Sequence Repeat (nSSR) markers, and characterized them using 24 individuals from a natural population. We then studied the intras...

Illegal logging and smuggling of Gonystylus bancanus (Thymelaeaceae) poses a serious threat to this fragile valuable peat swamp timber species. Using G. bancanus as a case study, DNA markers were used to develop identification databases at the species, population and individual level. The species level database for Gonystylus comprised of an rDNA (...

Illegal harvesting of forest resources poses a significant threat to the sustainability of forest ecosystems. Accurate wood species identification and the tracking of their geographical origins along the chain-of-custody are fundamental and necessary to fight illegal logging and associated trade. Since 2009, by using the DNA approach, the Forest Re...

Orthosiphon stamineus (Lamiaceae) is an important medicinal plant in Malaysia that has great potential in the herbal medicine industry. In this study, we developed and characterized ten microsatellites for O. stamineus. The microsatellite loci were checked for variability using 28 individuals of O. stamineus sampled from 10 nurseries. The number of...

Intsia palembanica is a high-value tropical hardwood species of the family Leguminosae. A total of 16 microsatellite markers were developed for this important timber species using an enrichment approach. These markers were screened on 24 samples from a natural population and subsequently tested for reproducibility, ease of scoring and locus-specifi...

• Premise of the study: The exploitation of Labisia pumila for commercial demand is gradually increasing. It is therefore important that conservation is prioritized to ensure sustainable utilization. We developed microsatellites for L. pumila var. alata and evaluated their polymorphism across var. alata, var. pumila, and var. lanceolata. • Methods...

Hopea bilitonensis is an extremely rare and predominantly selfing dipterocarp in Peninsular Malaysia. A comprehensive research was initiated to assess the ecological genetics of H. bilitonensis to elucidate specific ecological and genetic requirements and subsequently to recommend conservation strategies. The objective for conservation of a rare plan...

• Premise of the study: Microsatellite markers were isolated and characterized in Shorea platyclados (Dipterocarpaceae) for DNA profiling and genetic diversity assessment of this tropical timber species. • Methods and Results: Fifteen polymorphic microsatellite loci were developed and characterized in S. platyclados using a genomic library enriched...

Tropical rainforests in South-East Asia have been affected by climatic fluctuations during past glacial eras. To examine how the accompanying changes in land areas and temperature have affected the genetic properties of rainforest trees in the region, we investigated the phylogeographic patterns of a widespread dipterocarp species, Shorea leprosula...

Tectonic movements, climatic oscillations, and marine transgressions during the Cenozoic have had a dramatic effect on the biota of the tropical rain forest. This study aims to reveal the phylogeography and evolutionary history of a Peninsular Malaysian endemic tropical timber species, Neobalanocarpus heimii (Dipterocarpaceae). A total of 32 natura...

Premise of the study: Aggressive collections and trade activities in recent decades have resulted in heavy pressure on the natural stands of Aquilaria malaccensis and concerns over its long-term survival potential. To aid DNA profiling and assessment of its genetic diversity, microsatellite markers were developed for the species. Methods and resu...

Full-sib families are produced from artificially controlled pollination in tree breeding. This mating design is, however, very costly and logistically difficult as most tree species are large in size. With the development of molecular markers, known relationships among the offspring could be established from the maximum likelihood in paternity anal...

Cyt1 consensus tree constructed using the parsimony criterion. The tree was a summary of 100 trees with an equal length of 1,025 steps. The cyt1 data set comprised a 54-taxa data matrix with 1,191 characters of which 284 were parsimony informative. Conventions as in Figure S1. (TIF)

Nucleotide differences between cyt1 sequences of Odontotermes species. (DOCX)

16S consensus tree constructed using the parsimony criterion. The tree was a summary of 32,700 trees with an equal length of 615 steps. The 16S data set comprised a 50-taxa data matrix with 570 characters of which 341 were parsimony informative. The starting tree was obtained via stepwise addition and taxa were added according to the closest additi...

PCR primer sets and annealing temperatures Ta used for the amplification of mtDNA genes. (DOCX)

Termites of the genus Odontotermes are important decomposers in the Old World tropics and are sometimes important pests of crops, timber and trees. The species within the genus often have overlapping size ranges and are difficult to differentiate based on morphology. As a result, the taxonomy of Odontotermes in Peninsular Malaysia has not been adeq...

The extent of tropical forest has been declining, due to over-exploitation and illegal logging activities. Large quantities of unlawfully extracted timber and other wood products have been exported, mainly to developed countries. As part of the export monitoring effort, we have developed methods for extracting and analyzing DNA from wood products,...

Microsatellite markers of an important medicinal plant, Eurycoma longifolia (Simaroubaceae), were developed for DNA profiling and genetic diversity studies. Eighteen polymorphic microsatellite loci were developed for E. longifolia. The primers were designed from a genomic library enriched for dinucleotide (CT) repeats and screened on 32 samples fro...

One of the most crucial and interesting topics in tropical rainforest research is the pollination systems adapted to mast species, which flower massively at multiyear intervals. Highly fecund flower thrips are the primary pollinators and can respond rapidly to such an abrupt increase of flowers. Because thrips are minute and rather weak flyers, how...

Neobalanocarpus heimii, locally known as chengal, is an important timber species in Peninsular Malaysia. Owing to the high demand for its valuable timber, N. heimii is subjected to illegal logging and this species may become endangered in the near future. The present study was designed to identify a set of highly polymorphic short tandem repeat (ST...

Illegal logging poses a significant threat to the sustainability of tropical forest ecosystems. By using Neobalanocarpus heimii (Dipterocarpaceae) as an example, the study assessed the feasibility of using short tandem repeats (STRs) as a tool to identify the source of illegally logged timber. Thirty natural populations of N. heimii were profiled u...