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The United Nation’s Decade on Ecosystem Restoration 2021–2030 aims to halt ecosystem degradation to achieve Sustainable Development Goals (SDGs) by 2030. In Malaysia, the concept of sustainable forest management (SFM) has been practiced since 1901. In this study, we evaluated the genetic diversity of the native dipterocarp timber tree Shorea acuminata in a rehabilitated area at Kenaboi Forest Reserve (Kenaboi FR). The rehabilitated area was formerly a degraded forest managed with the taungya restoration system for 50 years. All trees with diameter at breast height (DBH) of 5 cm and over were measured, tagged and identified in a one-hectare study plot. A total of 132 inner bark samples were collected for DNA extraction. Four SSR markers (Sle280, Sle392, Sle475 and Sle566) and two EST-SSR markers (SleE07 and SleE16) were used to analyse 95 good-quality DNA samples. Genetic diversity parameters including maternal contribution were determined for 75 samples. The genetic diversity of big trees (He = 0.656 ± 0.19) and small trees (He = 0.652 ± 0.17) were high and both were in genetic equilibrium, with Fis values of the big trees being 0.035 and small trees being 0.164. Clustering analysis based on Jaccard’s similarity values (at 95% confidence level) confirmed that big trees in the Kenaboi FR rehabilitated area had originated from genetically diverse seed trees of the Sungai Menyala Forest Reserve which were used as the planting stock for the taungya restoration system. Maternal contribution showed that the allele contribution of the small trees came from the planted S. acuminata trees within the study area. The high genetic diversity of small trees in this study provides strong evidence that the existing big trees would be suitable for a genetically diverse seed collection to rehabilitate other degraded forests. Sustainable forest management must emphasise genetic diversity in order to ensure the resilience of rehabilitated forest ecosystems.

This study demonstrated that the cambial activities of three selected Shorea species with different stem diameters growing in a tropical rainforest in Malaysia responded differently to climatic factors. We investigated the cambial activities in Shorea leprosula, Shorea acuminata, and Shorea parvifolia trees with different stem diameters at breast height growing in a natural lowland dipterocarp rainforest in Malaysia. We collected and analyzed samples from the main trunks of selected trees in monthly intervals from March 2013 to April 2014. The cambium of the three Shorea species showed periods of active and less active growth in the humid forest. Selected trees with different stem diameters of the same and different species showed variation in rhythms of cambial activity (changes in the numbers of cambial and enlarging cell layers) at site with similar growing conditions. Monthly mean relative humidity and monthly mean vapour pressure deficit were important factors influencing the number of cambial cells of S. acuminata with larger stem diameter, and those of S. parvifolia with different stem diameters. Active cambium were detected in months with high relative humidity and low vapour pressure deficit in those trees. Total monthly precipitation had significant positive correlation with the cambial cells activities of S. parvifolia with different stem diameters, but no correlation with those of the other two species. The cambium of S. leprosula with smaller and larger stem diameters were found active throughout the year. We concluded that the three Shorea species examined with different stem diameters have different growth strategies and thus react differently to climatic factors.

Chemical composition, antioxidant and antibacterial properties of the essential oils from the stem and leaves of Shorea acuminata Dyer were investigated. The yield of the hydro-distilled essential oils obtained from stem and leaves were 0.40 % and 0.02 %, respectively. The main groups of compound found in the essential oils were sesquiterpene hydrocarbons (64.8 % and 33.4 %) and oxygenated sesquiterpenes (19.2 % and 51.7 %), which accounted for 85.6 % of the stem oil and 85.8 % of the leaf oil. Caryophyllene oxide (36.0 %) and β-caryophyllene (13.9 %) were found to be the major constituents in the leaves, whereas germacrene D (35.0 %) was the major constituent in the stem. The essential oils from the stem and leaves exhibited good antioxidant activity as measured by DPPH free radical-scavenging ability with EC50 of 0.72 mg/ml and 0.64 mg/ml respectively. In β-carotene/linoleic acid assay, the stem and leaves essential oil exhibited 88.78 % and 89.27 % antioxidant activity respectively at 9 mg/ml ...

Zulfahmi, Siregar IZ, Siregar UJ (2010) Chloroplast DNA variation of Shorea acuminata Dyer in Sumatra assessed by microsatellite markers. Biodiversitas 11: 107-111. Shorea acuminata Dyer is member of the Dipterocarpaceae family. It is ecologically and commercially important in the Indonesian region. In the present study, chloroplast microsatellites (cpSSRs) were used to study the distribution of chloroplast DNA haplotypes and to assess the variation within and among populations of S. acuminata from Riau and Jambi provinces eastern part of Sumatra. Based on chloroplast microsatellite analysis, six haplotypes were observed for S. acuminata,namely haplotype P, Q, R, S, T, and U, respectively. The high haplotype variation was detected in Bukit Barisan National Park (TNBT) population (five haplotypes); it may be due to TNBT population status as national parks (conservation area) under government protection. The value of genetic differentiation measured for S. acuminata was Gst = 0.150. The Gst values in this study is lower than the mean Gst value estimated in angiosperms plant for maternally inherited. Information on the status of genetic variation of the species in this study could be used as scientific consideration in formulating appropriate strategies for conservation and sustainable utilization ofgenetic resources.Key words: Dipterocarpaceae, Shorea acuminata, chloroplast microsatellites, genetic variation

In the conservation and management practices of natural forests, sound reproduction and regeneration form the basis of the maintenance and viability of the tree populations. To obtain and serve biological information for sustainable forest management, we investigated reproductive biology and inbreeding depression in seeds of an important dipterocarp tree species, Shorea acuminata (Dipterocarpaceae), by both field and laboratory experiments. Results of parental analysis of immature and mature seeds showed that selfing rates varied greatly, from 7.6 to 88.4% among eight mother trees, and the mean overall selfing rate was 38.3%. Observed outcrossing events within a 40-ha study plot were predominantly (76.5%) short-distance events with a mating distance (md) ≤ 100 m. Since the selfing rate sharply decreased with increase in the number of flowering conspecifics (i.e., individuals of the same species) within a 100-m radius from the mother trees, the local density of flowering conspecifics appears to be the key factor determining the outcrossing rate in S. acuminata. However, the extremely high selfing rate (88.4%) observed for one tree could not be simply explained by the low local density of flowering conspecifics. Instead, differences in its flowering phenology (its flowering peaked ca. a week earlier than most of the other examined individuals) may have severely limited its receipt of pollen from other conspecifics, and thus promoted selfing. Since there were no significant differences in the proportion of selfed progeny between immature and mature seed stages, there was no evidence of selective abortion of selfed seeds during seed development. However, the seed mass of outcrossed progeny was heavier than that of selfed progeny, and heavier seeds showed higher success rates at germination and seedling establishment. These results suggest that inbreeding depression resulted in reductions in seed mass and may reduce the fitness of selfed seeds in S. acuminata. In addition, the outcrossing rate of S. acuminata was more sensitive to low local conspecific flowering-tree densities than that of a sympatric bee-pollinated dipterocarp species with greater pollination distances. These results suggest that the management of local adult-tree densities is important for avoiding selfing and inbreeding depression in future generations, especially in a species like S. acuminata with predominantly short-distance pollination.

Shorea acuminata Dyer, Shorea curtisii Dyer ex King, Shorea leprosula Miq., and Shorea parvifolia Dyer are dominant tree species in the tropical rainforest of Peninsular Malaysia, which experienced several climatic changes during Pleistocene. To investigate the current population structure and demographic history of these species, we analyzed levels and patterns of nucleotide polymorphism of the nuclear gene region PgiC. We also used sequence data of the GapC gene region obtained in our previous study. Negative Tajima’s D values observed in both investigated gene regions for S. curtisii, S. leprosula, and S. parvifolia implied that all three species have experienced population expansion events. Little to moderate levels of population differentiation in S. acuminata and S. curtisii suggested recent divergence of the investigated populations after postglacial colonization of the Peninsular Malaysia. In addition, some haplotypes were similar or identical to haplotypes of the other species. The existence of such haplotypes could be partially explained by interspecific hybridization. Indeed, we found some putative hybrid individuals. Interspecific hybridization among closely related species might have contributed to the polymorphism of the investigated species.

A descriptive study of species composition, community structure and biomass was conducted in compartment 107, which is a rehabilitated area at Kenaboi Forest Reserve, Jelebu, Negeri Sembilan. The objective is to determine the forest structure and species composition in a rehabilitated area of Kenaboi FR since enrichment planting had done. A sample plot of 1 hectare was censused and a total of 395 trees with diameter ≥ 5 cm DBH were recorded. A total of 285 individual trees were identified belonging to 20 families and the commonest family was Dipterocarpaceae with 193 individuals. The highest tree density per ha was Shorea acuminata at 33% followed by S. parvifolia, 10% and S. leprosula, 6%. The biggest tree was Artocarpus elasticus Reinw. ex Blume with a diameter of 101 cm. The total basal area was 34.48 m2/ha, whereby the highest basal area was between 45 – 54.9 cm DBH class that contributed 10.21 m2/ha (30%). The total biomass estimation (above ground and below ground) was 792.57 t/ha. Dipterocarpaceae contributed the highest total biomass at 545.14 t/ha with S. acuminata contributed the highest total biomass of 330.45 t/ha. This study will contribute to the knowledge of regeneration forest especially on how the ecological process restoring the biodiversity and ecosystem functioning in rehabilitated forest by practicing the enrichment planting of native species.

Very little is known about the levels and patterns of DNA polymorphism in populations of tropical trees. In this study, we investigated population genetic structure of the four following Shorea species: Shorea acuminata, S. curtisii, S. leprosula and S. parvifolia from peninsular Malaysia using DNA sequences of Glyceraldehyde-3-phosphate dehydrogenase nuclear gene (GapC). The average nucleotide diversities of the investigated species for silent sites (πsil= 0.0027) were lower than those reported for herbaceous plants, and similar or somewhat lower than those of other woody species. These low levels of nucleotide diversities may be caused by small effective population size of Shorea species. We found that some individuals harbored atypical haplotypes consisting of sequences from two different species. The segmented architecture of these haplotypes suggests past inter-specific gene exchange and fertility of the hybrids. As demonstrated in this study analysis of DNA sequences provides genetic evidence for the occurrence of inter-specific hybridization and gives important insights into its evolutionary effects.

Antioxidant activity of crude methanol extracts of five Dipterocarpaceae species; Shorea ovalis (Meranti Kepong), Shorea resinosa (Meranti Belang), Shorea leprosula (Meranti Tembaga), Shorea acuminata (Meranti Rambai Daun) and Shorea macroptera (Meranti Melantai) from UiTM Jengka Forest Reserve were successfully being studied. The activities were determined by using four methods which are Total Phenolic Content (TPC) method, 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) method, ferric thiocyanate (FTC) and thiobarbituric acid (TBA) method. Among all the Shorea extracts analyzed, S. acuminata (Meranti Rambai Daun) showed the highest total phenolic content (2731.00 ± 0.09 mg GAE/ 100 g weight). A good correlation was found between the results of radical scavenging activity and total phenolic contents where S. acuminata (Meranti Rambai Daun) containing the highest total phenolic contents exhibited the strongest antioxidants potential. Meanwhile, S. macroptera (Meranti Melantai) has indicated the highest antioxidant for the FTC and TBA methods, respectively. This study also revealed that antioxidant activities of these Malaysian Dipterocarpaceae species can be used as a potential source of natural antioxidants and may give new alternative for medical cure.

We monitored the reproductive status of all trees with diameters at breast height (dbh) >30 cm in a 40-ha plot at Pasoh, west Malaysia, and investigated the individual fecundity of 15 Shorea acuminata Dyer (Dipterocarpaceae) trees using seed-trapping methods during two consecutive general flowering periods in 2001 (GF2001) and 2002 (GF2002). The proportion of flowering trees was higher, and not dependent on size, in GF2002 (84.2%), than in GF2001 (54.5%), when flowering mainly occurred in trees with a dbh ≤70 cm. Fecundity parameters of individual trees per event varied widely (221,000–35,200,000 flowers, 0–139,000 mature seeds, and 1.04–177 kg total dry matter mass of fruit (TDM) per tree). Monotonic increases with increasing tree size were observed for flower production and TDM amongst trees up to 90 cm in dbh, but not for mature seed production or for any of these parameters amongst larger trees. The pattern of reproductive investment during the two consecutive reproductive events clearly differed between medium-sized and large trees; the former concentrated their reproductive investment in one of the reproductive events whereas the latter allocated their investment more evenly to both reproductive events. Our results suggest size-related differences in the resource allocation pattern for reproduction.

Hopeanolin (1) was isolated from the acetone extract of the twigs of Shorea acuminata (Dipterocarpaceae), together with four resveratrol oligomers namely (-)-laevifonol, (-)-� -viniferin, (-)-vaticanol B and (-)-hopeaphenol. The structures of these compounds were established based on spectroscopic evidence, including UV, IR, NMR and mass spectra. Compound 1 showed the potent ability to protect � -carotene bleaching by linoleic acid and also to scavenge DPPH radicals with IC50s 0.18 and 6.58 mM respectively. The presence of compound 1 and the other four resveratrol oligomers in this species have great chemotaxonomic significance on the relationship between Shorea and other genera of Dipterocarpaceae especially Hopea.

Uninoculated dipterocarp seedlings raised in normal field soil in nurseries were always found to have mycorrhizas after a few months. This study set out to determine whether dipterocarp seedlings could continue to grow and develop in the absence of mycorrhizas and also to determine possible sources of mycorrhizal infection of dipterocarp seedlings raised under laboratory conditions using Shorea acuminata as a typical example. Seedlings were planted in capped or uncapped perspex boxes containing sterile or non-sterile field soil and watered daily with sterile water or tap water. Seedling growth and development of mycorrhizas were monitored at monthly intervals for up to seven months. Seedlings grown in sterile soil remained uninfected after seven months while infection was found in some of the seedlings grown in normal soil regardless of whether they had been watered with tap water or sterile water. This showed that field soil (i.e. under grass) far from the forest contained suitable inoculum for forest tree seedlings. Tap water and the air were not important sources of infection. However, mycorrhizal infection was very uneven indicating that the inoculum was probably very unevenly distributed in the soil or that the inoculum density was rather low. Seedlings grown in sterile soil showed better growth than those grown in normal soil and infection of roots by parasitic fungi in the latter was also observed. Key words: Mycorrhizas/Plant pathology/lnfections/Shorea acuminata/Seedlings.

Structures previously assigned to the two cis-diols from osmium tetroxide oxidation of methyl olean-2,12-dien-28-oate should be interchanged; 2α,3α-dihydroxyolean-12-en-28-oic acid occurs in Shorea acuminata resin.

Application of N.M.R. methyl resonance data led to revision of the structures given to the two cis 2,3-diols resulting from osmium tetroxide oxidation of methyl oleana-2,12-dien-28-oate (10). 2α,3α-Dihydroxyolean-l2-en-28-oic acid (6a), a new natural product, occurs in Shorea acuminata resin. Other constituents are 2α-hydroxy-ursolic acid (14a), mangiferonic acid (15b), and asiatic acid (14c). S. resina-nigra contains β-amyrin (16a), ursolaldehyde (14f), and Ψ-taraxesterol(17a).