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Triterpenoids of natural origin are of increasing interest due to their broad spectrum of biological activities. Previous studies on dipterocarpaceous plants have reported that they were valuable source of new active natural compounds. As part of an ongoing search for naturally occurring bioactive triterpenoids from Dipterocarpaceae, phytochemical investigation of Dipterocarpus costatus Gaertn. f. heartwood collected in Thailand was conducted. Seventeen triterpenoids (1 - 17) belonging to both 28-norlupane and dammarane series were isolated from the corresponding bioactive n -hexane extract. Among them, norlupane 1 was identified as previously undescribed and norlupane 2 was described for the first time from a natural source. Compound structures were elucidated by 1D/2D-NMR spectroscopy and mass (HRMS) spectrometry. All isolated molecules were tested for their cytotoxicity on two human colorectal carcinoma cell lines (i.e. HT-29 and HCT116), as well as for their antiplasmodial activity against chloroquine-resistant strain FcB1 of Plasmodium falciparum. Norlupanes 2 and 4 were shown to exhibit a good cytotoxic activity against HCT 116 (IC 50 =4.2 µM) and potent antiplasmodial activity (IC 50 =3.74 µM), respectively. [Display omitted] • To date, limited information is available regarding the phytochemistry of Dipterocarpus costatus. • Investigation was conducted on Dipterocarpus costatus heartwood collected in Thailand • Isolated triterpenoids belong to both 28-norlupane and dammarane series • Norlupane 2 has significant cytotoxic activity against HCT116 cell line (IC 50 =4.2 µM) • Norlupane 4 has potent activity against Plasmodium falciparum (IC 50 =3.74 µM). [ABSTRACT FROM AUTHOR]

Protecting rare and endangered species from habitat loss caused by climate and land use changes is crucial for stopping unprecedented biodiversity loss. Data on species' future range shifts is crucial in protected area management planning to establish proper refuges. This study focused on identifying the suitable habitat, vulnerabilities, and conservation gaps of Vatica guangxiensis—a canopy tree species endemic to the subtropical forests of southwest China and listed as Endangered in the IUCN Red List— through Maxent species distribution modeling using current and future climate data. Results showed that the predicted suitable habitats for V. guangxiensis under current climate were more extensive than its known range, encompassing parts of China, northern Laos, northern Vietnam, and eastern Myanmar. They are most likely to be in wetter regions with acidic soils. However, these habitats were predicted to decrease by 90% and shift to lower latitudes and higher elevations by 2081–2100 due to climate change, which leads to habitat loss for five out of twelve current wild populations, as well as severe fragmentation and reduced protected area coverage. Our findings demonstrate the potential for new field discoveries of V. guangxiensis based on its predicted distribution under current climate, but also show the vulnerability of its habitats under future climate change. We present a dire outlook for V. guangxiensis and highlight the need for field discovery of new populations and the establishment of ex situ populations that are explicitly guided by suitable habitat predictions. Furthermore, this study can contribute to the expansion of climate-informed protected areas in the Indochina region, to support the flagship '30 × 30' target for protected areas under the Kunming-Montreal Global Biodiversity Framework. Lastly, our findings elucidate the importance of transboundary conservation efforts, such as the Lancang-Mekong Cooperation Five-Year Action Plan, in preserving biodiversity and achieving global conservation goals. [ABSTRACT FROM AUTHOR]

Dipterocarpus retusus Blume is an endangered species on the IUCN Red List. In this study, we reported the complete chloroplast (cp) genome of D. retusus (GenBank accession number: OP271853). The cp genome was 154,303 bp long, with a large single-copy (LSC) region of 85,586 bp and a small single-copy (SSC) region of 20,273 bp separated by a pair of inverted repeats (IRs) of 24,222 bp. It encodes 128 genes, including 84 protein-coding genes, 36 tRNA genes, and eight ribosomal RNA genes. We also reconstructed the cp genome phylogeny of Dipterocarpus, which indicated D. retusus was closely related with the sympatric species D. gracilis. This study may contribute valuable information to the phylogenetic relationships within the genus Dipterocarpus. [ABSTRACT FROM AUTHOR]

Plant-derived natural products have consistently served as a rich source of bioactive compounds with potential therapeutic applications, particularly in anticancer treatments. These compounds have significantly contributed to advancements in drug discovery and development. Among the diverse array of plant species, the genus Shorea, which belongs to the family Dipterocarpaceae, has attracted attention due to its rich phytochemical profile and pharmacological properties. A bioassay-guided investigation of the wood of Shorea beccariana resulted in the isolation of 3-Omethylellagic acid 3'O-a-rhamnoside. The structure of this compound was determined using comprehensive structural elucidation techniques, including 1D and 2D NMR spectroscopy, UV spectroscopy, and FTIR analysis. Pharmacokinetic studies on the isolated compound demonstrated positive results, meeting several criteria for drug candidates, including bioavailability, ADMET, and drug-likeness properties. Furthermore, in silico molecular docking analysis of the compound using Dock6 revealed its ability to inhibit cyclin-dependent kinase 9 (CDK9) and 17ß-hydroxysteroid dehydrogenase type 1 (HSD17ß1) enzymes at molecular level, with a good conformational interaction and binding free energy of - 68.88 kcal/mol and -63.93 kcal/mol, respectively. The potent binding affinity of the compound with both target enzymes was found to be better than the reference inhibitors making it a highly promising candidate for an anticancer drug. However, further research on the molecular dynamic simulation and experimental validation (in vitro and in vivo studies) of the isolated compound is required to deeply understand the underlying mechanisms behind this interaction. The isolated secondary metabolite compound is being reported for the first time from the plant species. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of three species of Malaysian Dipterocarpus contributed to the isolation of 22 compounds which consist of 15 oligostilbenoids, 2 terpenes, 2 coumarins, and 3 flavonoids. The isolation of flavonoids in the Dipterocarpaceae family is very limited. Moreover, 4-methoxepigallocatechin-3-O-O-(3-methyl) gallate (20) was isolated for the first time in the plant. The occurrence of 4-O-methylgallocatechin (18) and its stereoisomer; 4-O’-methylepigallocatechin (19) was first reported in the Dipterocarpaceae family. This study also reported the existence of several types of oligostilbenoids such as davidiol A (8), stenophyllol B (9), isohopeaphenol (11), resveratrol (1), and ampelopsin E (10) which are the first occurrence in Dipterocarpus genus and suggested a significant chemotaxonomic relationship between Dipterocarpus, more closely to Vatica which is classified under Dipterocarpeae tribe.

Tropical and subtropical trees provide key ecosystem services but are facing global population decline due to logging, habitat degradation, land conversion, and climate change. Vatica guangxiensis used to be a characteristic timber species of China's tropical forests but is now terminally endangered (280 individuals) and fragmented into three relictual populations in southwest China. Generating genome‐wide DNA for ∼82% of all living tree individuals of this species complex, we found evidence for a late Pliocene division into two species‐level lineages that have not had gene flow for approximately 3 million years. All three relictual populations exhibited a loss of genetic diversity and recent bottlenecks. In addition, forward simulations indicated a likely population collapse in all three populations within the next century. Our study generates a model framework for the integration of genomic evidence—including evolutionary history, current genetic variation, and future projections—into conservation planning. [ABSTRACT FROM AUTHOR]

The article presents a study on the growth pattern among different populations of Shorea robusta and identified the best population which can serve as the seed source for raising seedlings and establishing the plantations. Shorea robusta is one of the most important timber species of the family Dipterocarpaceae. The researchers analyzed the correlation among traits and the genetic assessment and variation and morphological diversity among different populations for growth contributing trait.

IntroductionParashorea chinensis Wang Hsie (Pc) is an endangered tree species endemic to tropical and subtropical China. However, the acidic red soil areas where it is distributed generally face nutrient limitation. The study of the effects of mixed planting on soil biogeochemical processes contributes to the sustainable management and conservation of Pc.MethodsWe selected pure and mixed stands of Pc and collected its rhizosphere and bulk soil samples to clarify the effect of mixed planting on the soil microbial community and the nutrient status.ResultsThe results showed that (1) All stands were strongly acidic phosphorus-deficient soils (pH

Most canopy species in lowland tropical rain forests in Southeast Asia, represented by Dipterocarpaceae, undergo mast reproduction synchronously at community level during a general flowering event. Such events occur at irregular intervals of 2–10 years. Some species do not necessarily participate in every synchronous mast reproduction, however. This may be due to a lack of carbohydrate resources in the trees for masting. We tested the hypothesis that interspecific differences in the time required to store assimilates in trees for seed production are due to the frequency of masting and/or seed size in each species. We examined the relationship between reproductive frequency and the carbon accumulation period necessary for seed production, and between the seed size and the period, using radiocarbon analysis in 18 dipterocarp canopy species. The mean carbon accumulation period was 0.84 years before seed maturation in all species studied. The carbon accumulation period did not have any significant correlation with reproductive frequency or seed size, both of which varied widely across the species studied. Our results show that for seed production, dipterocarp masting species do not use carbon assimilates stored for a period between the masting years, but instead use recent photosynthates produced primarily in a masting year, regardless of the masting interval or seed size of each species. These findings suggest that storage of carbohydrate resources is not a limiting factor in the masting of dipterocarps, and that accumulation and allocation of other resources is important as a precondition for participation in general flowering. [ABSTRACT FROM AUTHOR]

Monoterpenoids are typically present in the secretory tissues of higher plants, and their biosynthesis is catalyzed by the action of monoterpene synthases (MTSs). However, the knowledge about these enzymes is restricted in a few plant species. MTSs are responsible for the complex cyclization of monoterpene precursors, resulting in the production of diverse monoterpene products. These enzymatic reactions are considered exceptionally complex in nature. Therefore, it is crucial to understand the catalytic mechanism of MTSs to elucidate their ability to produce diverse or specific monoterpenoid products. In our study, we analyzed thirteen genomes of Dipterocarpaceae and identified 38 MTSs that generate a variety of monoterpene products. By focusing on four MTSs with different product spectra and analyzing the formation mechanism of acyclic, monocyclic and bicyclic products in MTSs, we observed that even a single amino acid mutation can change the specificity and diversity of MTS products, which is due to the synergistic effect between the shape of the active cavity and the stabilization of carbon-positive intermediates that the mutation changing. Notably, residues N340, I448, and phosphoric acid groups were found to be significant contributors to the stabilization of intermediate terpinyl and pinene cations. Alterations in these residues, either directly or indirectly, can impact the synthesis of single monoterpenes or their mixtures. By revealing the role of key residues in the catalytic process and establishing the interaction model between specific residues and complex monoterpenes in MTSs, it will be possible to reasonably design and engineer different catalytic activities into existing MTSs, laying a foundation for the artificial design and industrial application of MTSs. [ABSTRACT FROM AUTHOR]

Abstract Tropical and subtropical trees provide key ecosystem services but are facing global population decline due to logging, habitat degradation, land conversion, and climate change. Vatica guangxiensis used to be a characteristic timber species of China's tropical forests but is now terminally endangered (280 individuals) and fragmented into three relictual populations in southwest China. Generating genome‐wide DNA for ∼82% of all living tree individuals of this species complex, we found evidence for a late Pliocene division into two species‐level lineages that have not had gene flow for approximately 3 million years. All three relictual populations exhibited a loss of genetic diversity and recent bottlenecks. In addition, forward simulations indicated a likely population collapse in all three populations within the next century. Our study generates a model framework for the integration of genomic evidence—including evolutionary history, current genetic variation, and future projections—into conservation planning.

The leaves, bark, and twigs of Dipterocarpus alatus have been used to treat many diseases because they contain large amounts of bioactive compounds that can protect against free radical damage. The extraction process is a key step in the utilization of bioactive compounds from plants. Therefore, the aim of this study was to determine the phytochemical compounds, antioxidant capacity and acetylcholinesterase (AChE) inhibitory activity of extracts of D. alatus leaves, bark and twig prepared using three extraction solvents with different polarities; methanol (MeOH), ethanol (EtOH) and isopropyl alcohol (IPA). The results revealed that the bark and twig extracts had a strong antioxidant activity, while the leaves had a potential AChE inhibitory activity. The strong antioxidant activity found in MeOH and EtOH extracts was related to their phenolic acid contents. A class of triterpenoid compounds, dipterocarpol and betulonic acid, which were abundant in the IPA extract, and their presence correlated with AChE inhibitory activity. Solvent polarity was therefore a critical extraction parameter affecting phytochemical content and biological activity. [ABSTRACT FROM AUTHOR]

Introduction: Shorea macrophylla is a commercially important tropical tree species grown for timber and oil. It is amenable to plantation forestry due to its fast initial growth. Genomic selection (GS) has been used in tree breeding studies to shorten long breeding cycles but has not previously been applied to S. macrophylla. Methods: To build genomic prediction models for GS, leaves and growth trait data were collected from a half-sib progeny population of S. macrophylla in Sari Bumi Kusuma forest concession, central Kalimantan, Indonesia. 18037 SNP markers were identified in two ddRAD-seq libraries. Genomic prediction models based on these SNPs were then generated for diameter at breast height and total height in the 7th year from planting (D7 and H7). Results and discussion: These traits were chosen because of their relatively high narrow-sense genomic heritability and because seven years was considered long enough to assess initial growth. Genomic prediction models were built using 6 methods and their derivatives with the full set of identified SNPs and subsets of 48, 96, and 192 SNPs selected based on the results of a genome-wide association study (GWAS). The GBLUP and RKHS methods gave the highest predictive ability for D7 and H7 with the sets of selected SNPs and showed that D7 has an additive genetic architecture while H7 has an epistatic genetic architecture. LightGBM and CNN1D also achieved high predictive abilities for D7 with 48 and 96 selected SNPs, and for H7 with 96 and 192 selected SNPs, showing that gradient boosting decision trees and deep learning can be useful in genomic prediction. Predictive abilities were higher in H7 when smaller number of SNP subsets selected by GWAS p-value was used, However, D7 showed the contrary tendency, which might have originated from the difference in genetic architecture between primary and secondary growth of the species. This study suggests that GS with GWAS-based SNP selection can be used in breeding for non-cultivated tree species to improve initial growth and reduce genotyping costs for next-generation seedlings. [ABSTRACT FROM AUTHOR]

While much research has focused on genetic variation in plants in relation to abiotic clines in temperate and boreal forests, few studies have examined similar relationships in tropical forests. Genetic variation in desirable performance traits of trees, such as drought tolerance, fast‐growth, and carbon sequestration rates, is widely used to improve reforestation efforts in nontropical systems. However, evolutionary processes such as local adaptation are poorly understood in tropical forests making it difficult to locate desired phenotypes. To test for genetic variation in growth rate in relationship to climatic clines, we conducted a common garden study over 18 months in a nursery using four dipterocarp tree species, represented by 9–12 half‐sib families, sourced across an elevational gradient ranging from lowland to hill forests (circa 130–470 m above sea‐level) in Malaysian Borneo. We found genetic variation in growth for all four species with fast‐growing half‐sib families growing 42–88% faster than poorly performing half‐sib families. Furthermore, in three species we found that elevation of seedling origin predicted seedling performance; in Shorea fallax and S. johorensis, half‐sib families originating from low elevations performed the best. In S. argentifolia half‐sib families' seedlings from low elevations grew slowly. Because elevation is a good proxy for climate, the finding of elevational clines predicting genetic variation in growth provides evidence of evolution affecting the function of tropical tree species. Our research highlights opportunities to better understand evolutionary processes in tropical forests and to use such information to improve seed source selection in reforestation. [ABSTRACT FROM AUTHOR]

Climatic factors have commonly been attributed as the trigger of general flowering, a unique community-level mass flowering phenomenon involving most dipterocarp species that forms the foundation of Southeast Asian tropical rainforests. This intriguing flowering event is often succeeded by mast fruiting, which provides a temporary yet substantial burst of food resources for animals, particularly frugivores. However, the physiological mechanism that triggers general flowering, particularly in dipterocarp species, is not well understood largely due to its irregular and unpredictable occurrences in the tall and dense forests. To shed light on this mechanism, we employed ecological transcriptomic analyses on an RNA-seq dataset of a general flowering species, Shorea curtisii (Dipterocarpaceae), sequenced from leaves and buds collected at multiple vegetative and flowering phenological stages. We assembled 64,219 unigenes from the transcriptome of which 1,730 and 3,559 were differentially expressed in the leaf and the bud, respectively. Differentially expressed unigene clusters were found to be enriched with homologs of Arabidopsis thaliana genes associated with response to biotic and abiotic stresses, nutrient level, and hormonal treatments. When combined with rainfall data, our transcriptome data reveals that the trees were responding to a brief period of drought prior to the elevated expression of key floral promoters and followed by differential expression of unigenes that indicates physiological changes associated with the transition from vegetative to reproductive stages. Our study is timely for a representative general flowering dipterocarp species that occurs in forests that are under the constant threat of deforestation and climate change as it pinpoints important climate sensitive and flowering-related homologs and offers a glimpse into the cascade of gene expression before and after the onset of floral initiation. [ABSTRACT FROM AUTHOR]

There is disparity between the estimated time of origin of the ‘superclade’ Dipterocarpaceae sensu lato, that includes Sarcolaenaceae, Cistaceae, Pakaraimaea, Bixaceae, Cochlospermaceae and Sphaerosepalaceae, as determined by recent molecular phylogenies (100−85 million years ago, Ma) and its strongly tropical, South American-African-Madagascan-SE Asian distribution that indicates an older Gondwanan origin (>110 Ma). We used several paleobiogeographic approaches, including recently reported fossil records, to explore the hypothesis that Dipterocarpaceae sl has a Gondwanan/early-Cretaceous origin.We created molecular phylogenies for this group, assigned each genus/family to the tectonic plate on which it is extant, and subjected the cladogram to areogram analysis. We also assessed ecological, mycotrophic and morphological traits, and global circulation patterns, as these might affect this group’s distribution.The initial analysis (omitting fossil evidence) showed that the crown of Dipterocarpaceae sl occurred concurrently on the South American and Madagascan plates. Including fossils from Africa and India changed this to a South American-African origin. Collectively, these origins represent NorthWest Gondwana with South America, Africa and Madagascar remaining conjoined until ≥105–115 Ma, setting the minimum age for this superclade with some evidence that it may be much older. We also show that the immediate ancestors of the three daughter lineages [Dipterocarpaceae- Sarcolaenaceae (in Africa/Madagascar, ≥115 Ma), Cistaceae- Pakaraimaea (South America/Africa/Eurasia, ≥105 Ma) and Bixaceae-Cochlospermum-Sphaerosepalaceae (South America/ Africa, ≥105 Ma)] also arose in NorthWest Gondwana.The immediate ancestors or basal species in Sarcolaenaceae, Sphaerosepalaceae, Dipterocarpaceae (both its subfamilies) and Bixaceae migrated from (South America)/Africa to Madagascar and we propose that the Dipterocarpoideae proceeded from Africa to India while still linked to Madagascar. In addition, much subsequent diversification of this superclade has occurred on the Eurasian, Indian, SE Asian (Sunda) and North American plates post-Gondwanan breakup.This long vicariant history is supported by fossil, ecological, mycotrophic and morphological traits, and global circulation patterns that show negligible propensity for transoceanic dispersal to explain this clade’s wide intercontinental distribution.We conclude that all these areocladogram/plate-breakup/ ecomorphological/circulation features are consistent with a Gondwanan/early-Cretaceous (>115 Ma) origin for the Dipterocarpaceae-Cistaceae-Bixaceae superclade plus its three daughter clades. Future analyses at the species level, exploring alternative diversification dates from both fossils and plate-tectonic dynamics, are needed to refine these findings.

In tropical Southeast Asia, Shorea is the most economically important tree and the largest genus in the Dipterocarpaceae family. It comprises about 150–200 species, of which majority are distributed in Malaysia, with others found in Sumatra and Borneo (Kalimantan) in Indonesia. Research on the chemical constituents of Shorea plants has been ongoing for many years. To date, a total of 113 different compounds, including 83 stilbenes and their resveratrol oligomers, 18 triterpenes/terpenoids, 7 coumarins 3 flavonoids and 2 steroids have been isolated and successfully elucidated from 26 different species of this genus. The diversity of the stilbene resveratrol oligomers in the Shorea genus is primarily due to the difference in the amount of resveratrol constituent units, which include dimers, trimers and tetramers. In addition to the species’ traditional usage in the treatment of illnesses, such as diarrhea, toothaches, skin diseases, ear troubles and wounds, the extracts and secondary metabolite compounds isolated from various parts of the plant species are known to have a very potent antioxidant, antimicrobial, anticancer, anti-diabetic, anti-obesity, antiulcer, hepatoprotective and nephroprotective activities. This review aims to summarize the most recent research made from 1999 to date on the secondary metabolite compounds isolated from different species of genus Shorea, as well as the bioactivity (in vitro and in vivo) of the crude extracts and the isolated secondary metabolite compounds.

Climatic factors have commonly been attributed as the trigger of general flowering, a unique community-level mass flowering phenomenon involving most dipterocarp species that forms the foundation of Southeast Asian tropical rainforests. This intriguing flowering event is often succeeded by mast fruiting, which provides a temporary yet substantial burst of food resources for animals, particularly frugivores. However, the physiological mechanism that triggers general flowering, particularly in dipterocarp species, is not well understood largely due to its irregular and unpredictable occurrences in the tall and dense forests. To shed light on this mechanism, we employed ecological transcriptomic analyses on an RNA-seq dataset of a general flowering species, Shorea curtisii (Dipterocarpaceae), sequenced from leaves and buds collected at multiple vegetative and flowering phenological stages. We assembled 64,219 unigenes from the transcriptome of which 1,730 and 3,559 were differentially expressed in the leaf and the bud, respectively. Differentially expressed unigene clusters were found to be enriched with homologs of Arabidopsis thaliana genes associated with response to biotic and abiotic stresses, nutrient level, and hormonal treatments. When combined with rainfall data, our transcriptome data reveals that the trees were responding to a brief period of drought prior to the elevated expression of key floral promoters and followed by differential expression of unigenes that indicates physiological changes associated with the transition from vegetative to reproductive stages. Our study is timely for a representative general flowering dipterocarp species that occurs in forests that are under the constant threat of deforestation and climate change as it pinpoints important climate sensitive and flowering-related homologs and offers a glimpse into the cascade of gene expression before and after the onset of floral initiation.

Vaticanol N (1) is a new resveratrol tetramer isolated from the acetone extract of Vatica bantamensis (Dipterocarpaceae) leaves. Spectroscopic analyses, including electrospray ionization–mass spectrometry and nuclear magnetic resonance, were used to analyze the structure of 1 , and its absolute configuration was determined using circular dichroism data. Notably, 1 is the first 8–8′ resveratrol tetramer produced via the 8–8′ cross-coupling of two 8–10′-coupled dimeric precursors with C–C-connected fused ring systems, a dihydrobenzofuran and hexacyclic tribenzobicyclo[3.3.2]decatriene, each with two and six asymmetric carbons. Moreover, a plausible biosynthetic pathway for 1 was proposed. The isolation of 1 exhibited further diversification of the resveratrol tetramer within the considered family. [Display omitted] • Vaticanol R is a resveratrol tetramer with a tribenzobicyclo[3.3.2]decatriene skeleton. • Vaticanol R is isolated from Vatica bantamensis. • Absolute configuration was determined based on NMR and CD spectral properties. • The isolation of 8 − 8′tetramer with one dihydrobenzofuran ring is the first instance. • The plausible biosynthetic pathway was proposed. [ABSTRACT FROM AUTHOR]

Vatica venulosa is one of the Dipterocarpaceae species that is threatened with extinction. Distributed in Peninsular Malaysia, Sumatra and Borneo, the tree is classified as Critically Endangered by IUCN Red List (International Union for Conservation of Nature) based on an assessment conducted in 1998. This assessment, however, was only based on the populations in Sumatra and Peninsular Malaysia. Therefore, this study aims to update the global conservation status of V. venulosa using all the occurrence records across the species' natural distribution. Reduction analysis and geographic range of the species were calculated based on the occurrence data stored in the Global Biodiversity Information Facility and scientific publications. Following IUCN Red List Categories and Criteria, the category Vulnerable (VU A4c) was proposed as the new global conservation status of the species. Under this category, V. venulosa is facing a high risk of extinction in the wild. Therefore, comprehensive conservation action is needed to prevent it from extinction. This study aims to update the global conservation status of Vatica venulosa using all the occurrence records across the species' natural distribution. Reduction analysis showed that the species experienced 30% population reduction over the past three generations. We proposed the category Vulnerable (VU A4c) as the new global conservation status of V. venulosa. [ABSTRACT FROM AUTHOR]

Shorea leprosula belongs to the Dipterocarpaceae family and grows in Indonesia's tropical forests which have an economic and ecological role. They are a plant in tropical forests that is known as a producer of fruit and tengkawang oil. The presence of S. leprosula trees in the habitat naturally at this time was very hard to find and began to decrease in population. This study aims to determine the potential and distribution pattern of S. leprosula found around KHDTK Aek Nauli. The research method uses the plot path method measuring 20 m × 20 m, the total number of plots is 150 plots. The research results show that the potency of S. leprosula is 63.17 m3 ha-1. The highest important value index of S. leprosula at the tree level was 25.45%. The distribution pattern of S. leprosula at the sapling, pole, and tree levels was clustered, while the distribution pattern at the seedling level was random. The importance of information about the potential and pattern of S. leprosula to be known as an indicator of the current status of its population at KHDTK Aek Nauli and as an information basis for managing management S. leprosula for support preservation in the forest. [ABSTRACT FROM AUTHOR]

Diaporthales is a species-rich order of fungi that includes endophytes, saprobes, and pathogens associated with forest plants and crops. They may also occur as parasites or secondary invaders of plant tissues injured or infected by other organisms or inhabit living animal and human tissues, as well as soil. Meanwhile, some severe pathogens wipe out large-scale cultivations of profitable crops, timber monocultures, and forests. Based on morphological and phylogenetic analyses of combined ITS, LSU, tef1-α, and rpb2 sequence data, generated using maximum likelihood (ML), maximum parsimony (MP), and MrBayes (BI), we introduce two new genera of Diaporthales found in Dipterocarpaceae in Thailand, namely Pulvinaticonidioma and Subellipsoidispora. Pulvinaticonidioma is characterized by solitary, subglobose, pycnidial, unilocular conidiomata with the internal layers convex and pulvinate at the base; hyaline, unbranched, septate conidiophores; hyaline, phialidic, cylindrical to ampulliform, determinate conidiogenous cells and hyaline, cylindrical, straight, unicellular, and aseptate conidia with obtuse ends. Subellipsoidispora has clavate to broadly fusoid, short pedicellate asci with an indistinct J-apical ring; biturbinate to subellipsoidal, hyaline to pale brown, smooth, guttulate ascospores that are 1-septate and slightly constricted at the septa. Detailed morphological and phylogenetic comparisons of these two new genera are provided in this study. [ABSTRACT FROM AUTHOR]

Leaf litter is an essential functional aspect of forest ecosystems, acting as a source of organic matter, a protective layer in forest soils, and a nurturing habitat for micro- and macro-organisms. Through their successional occurrence, litter-inhabiting microfungi play a key role in litter decomposition and nutrient recycling. Despite their importance in terrestrial ecosystems and their abundance and diversity, information on the taxonomy, diversity, and host preference of these decomposer taxa is scarce. This study aims to clarify the taxonomy and phylogeny of four saprobic fungal taxa inhabiting Dipterocarpus alatus leaf litter. Leaf litter samples were collected from Doi Inthanon National Park in Chiang Mai, northern Thailand. Fungal isolates were characterized based on morphology and molecular phylogeny of the nuclear ribosomal DNA (ITS, LSU) and protein-coding genes (tub2, tef1-α, rpb2). One novel saprobic species, Ciliochorella dipterocarpi, and two new host records, Pestalotiopsis dracontomelon and Robillarda australiana, are introduced. The newly described taxa are compared with similar species, and comprehensive descriptions, micrographs, and phylogenetic trees are provided. [ABSTRACT FROM AUTHOR]

The Janzen–Connell hypothesis proposes that density and distance‐dependent mortality generated by specialist natural enemies prevent competitive dominance. Much literature on Janzen–Connell mechanisms comes from the neotropics, and evidence of the role of distance and density‐dependence is still relatively sparse. We tested the predictions of the Janzen–Connell hypothesis in a South‐East Asian system dominated by mast fruiting species. We hypothesized that seedling survival would decrease with distance and density, seedling growth would increase, and herbivory would decrease, according to the predictions of the Janzen–Connell hypothesis. Experiments were conducted to determine the strength of the Janzen–Connell mechanism by manipulating the density and identity of tree species as a function of the distance from parent trees. Survival of conspecific seedlings was reduced near adult trees of one species, but not another. High densities of seedlings decreased the growth of conspecific seedlings of both species. In both species, herbivory rates decreased with distance in low‐density areas. This study indicates that dipterocarp species experienced weak Janzen–Connell effects of distance and density dependence at the growth stage studied. Future studies in this system might focus on earlier life‐history stages such as seeds and small seedlings, as well as studying mortality during mast‐seeding events. [ABSTRACT FROM AUTHOR]

Indonesia, particularly the island of Java, is dominated by a number of Shorea tree species (Dipterocarpaceae). Trees of the genus have been utilized for various practices, and they play a fundamental role in managing the stability of tropical forests. This study was carried out to understand the relationships between biomass and microfibril angle in Shorea spp. growing in West Java, where Shorea spp., are abundant. A total of 35 young trees belonging to 5 species were studied. The average age of these trees was 9 years, but in general there was a wide variation in tree diameter and total height. On average, biomass was the highest in S. leprosura and the lowest in S. palembanica. The lowest average microfibril angles (MFAs) were found in S. leprosura and S. mecistopteryx. The regression relationship between biomass and diameter was strong with an R2 value of 0.85, while the strength of the relationship between MFA and diameter was weaker (R2 = 0.195). In general, the MFA degree decreased with increased biomass accumulation Shorea species, which affects tree resistance to environmental variables and competitiveness in Indonesian tropical forests. [ABSTRACT FROM AUTHOR]

Southeast Asia supports high biodiversity, in a mosaic of forest types formed by the expansion and contraction of habitats through past climate changes. Among the region's forest types, the geographical distribution of peat swamp forests has fluctuated intensely over the past 120,000 years. Most peat swamp forests in Southeast Asia are found in coastal regions and formed within the last 7,000 years after a decline in sea level. However, some peat swamps were initiated earlier on substrates of slightly higher elevation, and these peat swamps might have been refugia for peat swamp species in the last glacial period and the high sea level period. We assessed genetic diversity, genetic structure and divergence time of current genetic groups for Shorea albida in Brunei, an endemic tree species of Bornean peat swamp forests, using 18 microsatellite markers. Genetic diversity was not lower than has been found in other Shorea species, possibly because of the high density of S. albida in Brunei. Although overall genetic divergence between populations was low, two populations (Ingei and Labi Road 3) were distinct from the other populations. Analysis using DIYABC estimated that three genetic groups (Ingei, Labi Road 3 and others) diverged simultaneously from their ancestral population, whose effective size was very small, about 7,500 years ago, corresponding to a recent sea level peak in the Belait-Baram river basin. In that high sea level period, some higher-elevation lands remained, and peat formation had already started in this region. We propose that the current genetic structure of S. albida in Brunei was formed from small refugial populations that survived the period of higher sea level in these higher-elevation areas. Because of their relatively high genetic diversity, Brunei's S. albida populations should become an important genetic resource for the recovery of genetically healthy populations in other parts of northwest Borneo. [ABSTRACT FROM AUTHOR]

Shorea macrophylla belongs to the Shorea genus under the Dipterocarpaceae family. It is a woody tree that grows in the rainforest in Southeast Asia. The complete chloroplast (cp) genome sequence of S. macrophylla is reported here. The genomic size of S. macrophylla is 150,778 bp and it possesses a circular structure with conserved constitute regions of large single copy (LSC, 83,681 bp) and small single copy (SSC, 19,813 bp) regions, as well as a pair of inverted repeats with a length of 23,642 bp. It has 112 unique genes, including 78 protein-coding genes, 30 tRNA genes, and four rRNA genes. The genome exhibits a similar GC content, gene order, structure, and codon usage when compared to previously reported chloroplast genomes from other plant species. The chloroplast genome of S. macrophylla contained 262 SSRs, the most prevalent of which was A/T, followed by AAT/ATT. Furthermore, the sequences contain 43 long repeat sequences, practically most of them are forward or palindrome type long repeats. The genome structure of S. macrophylla was compared to the genomic structures of closely related species from the same family, and eight mutational hotspots were discovered. The phylogenetic analysis demonstrated a close relationship between Shorea and Parashorea species, indicating that Shorea is not monophyletic. The complete chloroplast genome sequence analysis of S. macrophylla reported in this paper will contribute to further studies in molecular identification, genetic diversity, and phylogenetic research.

Studying the spatial pattern of plant species can improve understanding of ecological processes and mechanisms that maintain forest stand stability. To better understand the population dynamics of two dipterocarp species Dipterocarpus costatus and Dipterocarpus alatus, in the semi-deciduous forest in Southern Vietnam, we used the spatial point-pattern analysis methods to evaluate the spatial patterns and the interaction of these two species. The results showed that the population structure of D. costatus and D. alatus was similar; their diameter distributions were reverse J-shaped, and the numbers of trees were high at the juvenile and premature stages. The spatial patterns of two dipterocarp species tend to shift from aggregation to randomness and regularity as the tree diameter increases. We found negative interactions between mature and premature trees of two dipterocarp species at small scales. Mature and premature trees of two dipterocarp species showed no inhibition with their juveniles. Seed dispersal and natural self-thinning may be two main processes that control the spatial distribution and association patterns of two dipterocarp species. With the obtained results, our study contributes to simulate the population dynamics of tropical forest trees by using time-replacing space. [ABSTRACT FROM AUTHOR]

A study related to species composition and diversity of sapling was conducted in the coastal hill forests at Pulau Pangkor, Perak. Six study plots of 20m x 20m (0.04 ha) each were established in Pangkor Utara Forest Reserve (two plots) and Pangkor Selatan Forest Reserve (four plots), making a total area of 0.24 ha. The composition of sapling species was represented by 460 individuals consisting of 52 species, 46 genera and 30 families. Dipterocarpaceae and Rubiaceae recorded the highest number of species with seven species each. At genus level, Diospyros recorded the highest number of species with three species. Sapling density of the study area was 1917 individuals/ha, where Dipterocarpaceae has the highest density with 588 individuals/ha while at species level, Hopea beccariana recorded 483 individuals/ha. Dipterocarpaceae was the most important family with Importance Value Index (IVi) of 21.11%, while the most important species was Hopea beccariana (IVi = 16.98%). Shannon Diversity Index, Evenness Index, and Margalef Richness Index were 2.99, 0.76, and 8.32, respectively. [ABSTRACT FROM AUTHOR]

3 Jul 1952) was fortunate in obtaining fossil wood that allowed him to determine the extant genus to which the Burmese fossils could be related: he recombined them in his previously published generic name, I Glutoxylon i K.A. Chowdhury (in Curr. He noted that several other problematic fossil wood types published under I Grewioxylon i awaited re-classification in different fossil wood genera, not even related to an extant " I Grewia i -like" fossil wood type. 1927) reviewed the fossil wood species referred to I Dipterocarpoxylon i by Kräusel (l.c. 1922, 1926) and assigned many of them to genera with quite different relationships. (2929-2931) Proposals to conserve the names Dipterocarpoxylon with a conserved type against Hippocrateoxylon, Dryobalanoxylon against Naucleoxylon, and Shoreoxylon against Bredaea and Grewioxylon (fossil Dipterocarpaceae, Magnoliophyta). [Extracted from the article]

It has been hypothesized that most Asian tropical lineages have originated in Gondwana with the Indian subcontinent playing a crucial role in the dispersal of ancestral Gondwanan taxa. The disjunct distribution of dipterocarps and the fossil record in India support the Gondwana hypothesis. This is the first comprehensive study addressing the evolutionary and biogeographic relationships of dipterocarps in the Indian subcontinent to test the Gondwana hypothesis. A Bayesian phylogenetic tree of the Dipterocarpaceae family including the Indian counterparts corroborates the monophyly of subfamilies/tribes and shows new biogeographic affinities. Molecular dating reveals the Cretaceous origin of Dipterocarpaceae. Diversification of major lineages occurred during the Pliocene‐Miocene epochs. The DEC analysis ascertains the Gondwanan origin and dispersal route from the Madagascar (Africa)‐India‐Sri Lanka‐Seychelles block to Eurasia. The biogeographic analysis suggests early vicariance followed by an out‐of‐India dispersal of Dipterocarpaceae. Three dispersal events from India to the remainder of Asia at 47.6 Ma, 42.53 Ma and 37.6 Ma are identified. There probably was a biotic interchange between India and mainland Asia via Sumatra following the collision of the Indian plate with Eurasia. Molecular dating and dispersal events coincide with the geological events. During the Miocene, uplift of the Himalayan‐Tibetian plateau induced climatic variation, which seems to have resulted in the extinction of major Indian dipterocarp lineages and reverse dispersal into India. Hopea‐Shorea, one of the earliest diverged lineages, originated in Southeast Asia. The establishment of Southeast Asian monsoon climate may have favoured allopatric speciation and diversification of Southeast Asian lineages also resulting in further dispersal into India. [ABSTRACT FROM AUTHOR]

Shorea leprosula is one of the tree species within Dipterocarpaceae Family, which is a major source of timber production. The species has been planted massively in Gunung Dahu Research Forest (GDRF) in Leuwiliang, Bogor. Gunung Dahu Research Forest is a manmade dipterocarp forest that has varying slope classes, topography, and canopy cover. Furthermore, natural regeneration is an important ecological factor in assessing the ability of forest regeneration, including in a plantation forest. Therefore, it is necessary to know the effect of slope and canopy cover on the regeneration of S. leprosula in order to characterize what factors support and constrain the naturally regenerating forest of Gunung Dahu Research Forest. Regeneration capacity of the species was observed in purposive plots which have been recorded for their flowering events. Seedlings were grouped into seedlings and saplings. It was measured by census method on every slopes. Meanwhile, variable observed included number of available seedlings at each slope category slope with its canopy cover, height and diameter of seedlings, and litter thickness. The results show that a flat slope with shady canopy cover has the highest capacity of seedlings and the best growth. The uneven distribution of height and diameter indicates the need for silviculture action, such as, maintenance. [ABSTRACT FROM AUTHOR]

Dipterocarp species dominate tropical forest ecosystems and provide key ecological and economic value through their use of aromatic resins, medicinal chemicals, and high-quality timber. However, habitat loss and unsustainable logging have endangered many Dipterocarpaceae species. Genomic strategies provide new opportunities for both elucidating the molecular pathways underlying these desirable traits and informing conservation efforts for at-risk taxa. This review summarizes the progress in dipterocarp genomics analysis and applications. We describe 16 recently published Dipterocarpaceae genome sequences, representing crucial genetic blueprints. Phylogenetic comparisons delineate evolutionary relationships among species and provide frameworks for pinpointing functional changes underlying specialized metabolism and wood development patterns. We also discuss connections revealed thus far between specific gene families and both oleoresin biosynthesis and wood quality traits-including the identification of key terpenoid synthases and cellulose synthases likely governing pathway flux. Moreover, the characterization of adaptive genomic markers offers vital resources for supporting conservation practices prioritizing resilient genotypes displaying valuable oleoresin and timber traits. Overall, progress in dipterocarp functional and comparative genomics provides key tools for addressing the intertwined challenges of preserving biodiversity in endangered tropical forest ecosystems while sustainably deriving aromatic chemicals and quality lumber that support diverse human activities. • Dipterocarp species, vital to tropical ecosystems, face endangerment due to habitat loss and logging. • Genomic strategies unveil molecular pathways behind key traits, aiding conservation efforts. • Review covers 16 recently sequenced Dipterocarpaceae genomes, offering crucial genetic insights. • Phylogenetic comparisons provide evolutionary context, aiding in understanding functional changes. • Identification of key genes linking to oleoresin biosynthesis and wood quality enhances knowledge. [ABSTRACT FROM AUTHOR]

While restoration projects globally scale-up to meet the growing demand to restore degraded ecosystems, data on the long-term benefits of restoration are still rare. Here, we describe the lessons learned from the Sow-A-Seed project in Sabah, Borneo: a long-term and large-scale restoration project launched in 1998 with the aim to rehabilitate 18,500 ha of tropical rainforest degraded by logging and forest fires. The project was built from the ground-up, including establishment of essential infrastructure and knowledge creation via trial-and-error. Three restoration techniques were used depending on the level of degradation; 1) Assisted Natural Regeneration (weeding, climber cutting and selective girdling) to promote natural regeneration of late-successional species in the least disturbed forests, and; 2) Enrichment Planting in gap-clusters in moderately disturbed forests, and; 3) Enrichment Planting in rows (i.e, line-planting) throughout heavily degraded forests with no- or few late successional tree species in the overstory. The project includes successful propagation of 92 native tree species including dipterocarps and fruit trees, and planting of over 5 million trees during the last 25 years. Long-term monitoring shows that the mortality rate of planted seedlings is ∼15% per year up to 3 years, but decreases to ∼2% between years 3–10 and 10–20. One of the largest trees, a Shorea leprosula planted in 1998, is now 74 cm in DBH and some planted trees have reached reproductive age and are contributing to natural regeneration. A range of wildlife including orangutans, elephants, hornbills and all five wildcat species in Sabah have been documented in the area. In 2015, the area was classified as a Class 1 protected forest, the highest level of conservation status in Malaysia, and removed from commercial forestry. We highlight that there is much knowledge to be gained by research dove-tailing with operational activities, and we encourage that the lessons learned from operational restoration are shared among practitioners and restoration ecologists. We present 8 key lessons learned from the Sow-a-Seed project. [ABSTRACT FROM AUTHOR]

Important plant area (IPA) is one of the global approaches to conserving threatened species and their habitats in situ. In the present study, we assess the risk of ecosystem collapse of Mursala Island and identify the island's potential as the first IPA site in Indonesia. Mursala Island is located on the west coast of the Sumatera Utara Province and is known as one of the hotspots for dipterocarps species diversity. Our compiled data records at least 178 species of plant on Mursala Island, which belong to 47 families. A total of 104 species have been assessed for their conservation status according to the IUCN Red List, of which 27 (25.96%) are threatened with extinction with the category of Critically Endangered (CR; 4), Endangered (10), and Vulnerable (13). The majority (24 or more than 88%) of these threatened species are from the Family Dipterocarpaceae. Following the IUCN Red List of Ecosystems protocol, we propose CR B1c as the risk category of Mursala Island's ecosystem. Under this category, the ecosystem is considered to be at an extremely high risk of collapse. Furthermore, our assessment shows that Mursala Island qualifies as an IPA under criteria Ai and Aii. Increasing the protection level of the island is recommended to conserve the ecosystem and its plant diversity. [ABSTRACT FROM AUTHOR]

Many companies are making ambitious pledges to achieve positive impacts for climate and nature by financing restoration of carbon- and biodiversity- rich natural habitats. However, companies cannot make evidence-based choices that will deliver successful restoration if the scientific information required to guide investment has not been synthesised in a way that they can use, or there are knowledge gaps. To explore this issue, share information, and identify knowledge gaps and research priorities, we bring together researchers, a conservation NGO and a multinational consumer goods company (Unilever), focusing on Southeast Asian rainforests. These habitats offer significant restoration opportunities for carbon and biodiversity in areas that have been degraded by commercial logging and agriculture. We find that procedures for carbon restoration are much better developed than those for biodiversity, and that new research is urgently needed to deliver evidence-based biodiversity restoration. Companies need to be confident that their actions are fit-for-purpose to meet their environmental pledges. Achieving successful restoration outcomes will require co-designed projects with the potential to deliver positive co-benefits for carbon, biodiversity and local livelihoods.

Summary: Fine‐scale topographic–edaphic gradients are common in tropical forests and drive species spatial turnover and marked changes in forest structure and function. We evaluate how hydraulic traits of tropical tree species relate to vertical and horizontal spatial niche specialization along such a gradient.Along a topographic–edaphic gradient with uniform climate in Borneo, we measured six key hydraulic traits in 156 individuals of differing heights in 13 species of Dipterocarpaceae. We investigated how hydraulic traits relate to habitat, tree height and their interaction on this gradient.Embolism resistance increased in trees on sandy soils but did not vary with tree height. By contrast, water transport capacity increased on sandier soils and with increasing tree height. Habitat and height only interact for hydraulic efficiency, with slope for height changing from positive to negative from the clay‐rich to the sandier soil. Habitat type influenced trait–trait relationships for all traits except wood density.Our data reveal that variation in the hydraulic traits of dipterocarps is driven by a combination of topographic–edaphic conditions, tree height and taxonomic identity. Our work indicates that hydraulic traits play a significant role in shaping forest structure across topographic–edaphic and vertical gradients and may contribute to niche specialization among dipterocarp species. [ABSTRACT FROM AUTHOR]

Shorea macrophylla is also named as 'Engkabang' (Iban), 'Kawang' (Brunei), and 'Tengkawang' (Indonesia). It belongs to the Dipterocarpaceae family and is categorised under the genus Shorea, which can be found in the tropical rainforests in Southeast Asia. It prefers wet habitats, such as in periodically flooded alluvium and riverbanks. The tree size of S. macrophylla is medium or large; however, some researchers in Kalimantan claim it is a small tree. The flowering and fruiting systems of most Dipterocarps, including S. macrophylla, are irregular, but there is a massive flowering event once every few years. Its genetic structure is characterised by moderate genetic diversity within species and populations, as well as high genetic differentiation within local populations. Shorea macrophylla, also known as the Light Red Meranti, is a suitable timber supply for light construction work. It produces illipe nuts that are widely used as cocoa butter replacer fat. Wildlife eats the ripe illipe nuts, which contain a high oil content with mostly beneficial unsaturated triglycerides. The fat extracted from the nut are suitable for cosmetic application as it provides a good moisturising effect. Future investigation into the illipe nuts' composition and other potential uses should be carried out. [ABSTRACT FROM AUTHOR]

Leaf litter is an essential functional aspect of forest ecosystems, acting as a source of organic matter, a protective layer in forest soils, and a nurturing habitat for micro- and macro-organisms. Through their successional occurrence, litter-inhabiting microfungi play a key role in litter decomposition and nutrient recycling. Despite their importance in terrestrial ecosystems and their abundance and diversity, information on the taxonomy, diversity, and host preference of these decomposer taxa is scarce. This study aims to clarify the taxonomy and phylogeny of four saprobic fungal taxa inhabiting Dipterocarpus alatus leaf litter. Leaf litter samples were collected from Doi Inthanon National Park in Chiang Mai, northern Thailand. Fungal isolates were characterized based on morphology and molecular phylogeny of the nuclear ribosomal DNA (ITS, LSU) and protein-coding genes (tub2, tef1-α, rpb2). One novel saprobic species, Ciliochorella dipterocarpi, and two new host records, Pestalotiopsis dracontomelon and Robillarda australiana, are introduced. The newly described taxa are compared with similar species, and comprehensive descriptions, micrographs, and phylogenetic trees are provided.

The interaction effects between climate and fire regime in controlling the type of vegetation and species composition is well established among the Earth's biomes. Climate and the associated fire regime are never stable for long, and annual temperatures, atmospheric carbon dioxide and oxygen levels, and burn probability have varied radically over the last 350 million years. At the scale of thousands of years, floras have oscillated between spreading and retracting as climate and the dependent fire regime have fluctuated. At the scale of millions of years, distinct traits have evolved along three lines: fire resistance, fire-stimulated dormancy release, and rapid postfire growth, all limited by the type of fire (as controlled by climate) and postfire weather. Eight pairings of fire- and postfire-related traits resulting from the interplay between fire and climate are noted here. Smoke-released seed dormancy is beneficial on two counts: it increases the chance of recruitment under the present fireprone climate and increases the chances of survival should the wet season shift to another time of year where temperatures are higher or lower. Four pathways can be recognized with respect to the fire regimes induced by climate changes: (1) from non-fireprone to fireprone habitats (gains fire-adapted trait, 13 studies covering the last 115 million years (My) described here); (2) from a surface fire to a crown fire-type habitat (gains a different fire-adapted trait, 13 studies); (3) from a crown fire-type to surface fire-type habitat (loss of fire-adapted trait, 12 studies); and (4) from moderately burnt (crown fire) to non-fireprone habitat, such as desert, rainforest, or alpine habitats (loss of fire-adapted trait, 6 studies). Four case studies, at decreasing taxonomic rank, are used to illustrate the intimate relationship between climate change with its associated vegetation and fire regime change as they promote adaptive trait evolution: gain then loss of heat-released seed dormancy in Dipterocarpaceae–Cistaceae–Bixaceae over 90 My, gain then loss of serotiny in Callitroid Cupressaceae over the last 65 My, gain then loss of smoke-released seed dormancy in Proteoid Proteaceae over the last 120 My, and gain then loss of resprouting and serotiny among Hakea species (Grevilleoid Proteaceae) over the last 20 My. Examples of within-species rates of migration and trait change, including a model describing increasing degree of serotiny with intensifying drought, are given. The relevance of this historical approach to current (anthropogenic) climate change and associated fire regime alteration is discussed. Despite major threats expected to species conservation status at both the macro-(biome) and micro-(population) scales, I conclude that insufficient time or opportunities remain for effective migration to less-stressed areas or suitable adaptive responses to climate/fire regime change to evolve. [ABSTRACT FROM AUTHOR]

The role of conspecific density dependence (CDD) in the maintenance of species richness is a central focus of tropical forest ecology. However, tests of CDD often ignore the integrated effects of CDD over multiple life stages and their long-term impacts on population demography. We combined a 10-year time series of seed production, seedling recruitment and sapling and tree demography of three dominant Southeast Asian tree species that adopt a mast-fruiting phenology. We used these data to construct individual-based models that examine the effects of CDD on population growth rates (λ) across life-history stages. Recruitment was driven by positive CDD for all species, supporting the predator satiation hypothesis, while negative CDD affected seedling and sapling growth of two species, significantly reducing λ. This negative CDD on juvenile growth overshadowed the positive CDD of recruitment, suggesting the cumulative effects of CDD during seedling and sapling development has greater importance than the positive CDD during infrequent masting events. Overall, CDD varied among positive, neutral and negative effects across life-history stages for all species, suggesting that assessments of CDD on transitions between just two stages (e.g. seeds seedlings or juveniles mature trees) probably misrepresent the importance of CDD on population growth and stability. [ABSTRACT FROM AUTHOR]

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 enforcement officials in ensuring only sustainably harvested timbers are traded in the market. In this study, we developed chloroplast DNA (cpDNA) and simple sequence repeat (SSR) databases as tracking tools for an important tropical timber tree species, Shorealeprosula from Peninsular Malaysia. A total of 1410 individual trees were sampled from 44 natural populations throughout Peninsular Malaysia. Four cpDNA regions were used to generate a cpDNA haplotype database, resulting in a haplotype map comprising 22 unique haplotypes derived from 28 informative intraspecific variable sites. This cpDNA database can be used to trace the origin of an unknown log at the regional level. Ten SSR loci were used to develop the SSR allele frequency database. Bayesian cluster analysis divided the 44 populations into two genetic clusters corresponding to Region A and Region B. Based on conservativeness evaluation of the SSR databases for individual identification, the coancestry coefficients (θ) were adjusted to 0.1900 and 0.1500 for Region A and B, respectively. These databases are useful tools to complement existing timber tracking systems in ensuring only legally sourced timbers are allowed to enter the wood supply chain. [ABSTRACT FROM AUTHOR]

Uliginoside H (1) is a new resveratrol trimer diglucoside derivative with fused heptacycles. It was discovered from the acetone extract of the stem bark of Shorea uliginosa (Dipterocarpaceae). Spectroscopic analysis, such as NMR experiments, was used to elucidate the structure, and the absolute configuration was determined using circular dichroism data. Notably, 1 has a fused ring system composed of a dihydrobenzofuran ring, a hexahydrocyclopenta[ c ]chromene ring, and a cyclohex-2-enone ring, each with eight asymmetric carbons. Thus, a plausible biosynthetic pathway for 1 was proposed. [Display omitted] • Uliginoside H is a C -di-glucoside of trimeric resveratrol. • Uliginoside H is isolated from Shorea uliginosa. • Absolute configuration was determined based on NMR and CD spectral properties. • Structure of the core heterocyclic skeleton bearing dearomatized ring was elucidated. • The plausible biosynthetic pathway was proposed. [ABSTRACT FROM AUTHOR]

While reforestation is gaining momentum to moderate climate change via carbon sequestration, there is also an opportunity to use tree planting to confront declining global biodiversity. Where tree species vary in support of diversity, selecting appropriate species for planting could increase conservation effectiveness. We used a common garden experiment in Borneo using 24 native tree species to examine how variation among tree species in their support of beetle diversity is predicted by plant traits associated with "acquisitive" and "conservative" resource acquisition strategies. We evaluate three hypotheses: (1) beetle communities show fidelity to host identity as indicated by variation in abundance and diversity among tree species, (2) the leaf economic spectrum partially explains this variation as shown by beetle preferences for plant species that are predicted by plant traits, and (3) a small number of selected tree species can capture higher beetle species richness than a random tree species community. We found high variation among tree species in supporting three highly intercorrelated metrics of beetle communities: abundance, richness, and Shannon diversity. Variation in support of beetle communities was predicted by plant traits and varied by plant functional groups; within the dipterocarp family, high beetle diversity was predicted by conservative traits such as high wood density and slow growth, and in non‐dipterocarps by the acquisitive traits of high foliar K and rapid growth. Using species accumulation curves and extrapolation to twice the original sample size, we show that 48 tree species were not enough to reach asymptote levels of beetle richness. Nevertheless, species accumulation curves of the six tree species with the highest richness had steeper slopes and supported 33% higher richness than a random community of tree species. Reforestation projects concerned about conservation can benefit by identifying tree species with a disproportional capacity to support biodiversity based on plant traits. [ABSTRACT FROM AUTHOR]

During the routine survey for exploring the hidden macrofungal wealth of tropical Sal (Shorea robusta Roth) forests in West Bengal and Jharkhand (India), we found a specimen similar to Tylopilus plumbeoviolaceous (Snell & E.A.Dick) Snell & E.A.Dick. After careful morphological observations and phylogenetic analysis, the species was found to be conspecific with Tylopilus glutinosus Iqbal Hosen, a recently established taxon from Bangladesh. We report T. glutinosus for the first time from India and provide a detailed description, figures, a multigene phylogenetic analysis, and comprehensive comparisons with similar species. A distributional map is also provided. [ABSTRACT FROM AUTHOR]

Community‐managed forests (CF) bordering protected areas are critical to conservation in Borneo. Iban‐managed CF retain tree species characteristic of primary forests within pulau, remnant old growth forests conserved for harvesting forest products. However, the selective felling of large trees, and proximity to surrounding mixed‐use mosaic habitat, likely influence pulau structure and composition. Tropical Asian forests exhibit supra‐annual mast fruiting (3–7 years) and extended periods of fruit scarcity, but fruit trees encouraged and planted by communities, in mixed‐use mosaic bordering pulau, may benefit wildlife during periods of fruit scarcity. We investigated seasonal availability of foods important to wildlife within protected primary forest and pulau at the boundary of the Lanjak Entimau Wildlife Sanctuary (LEWS), in Sarawak, Malaysia. We tracked the presence of fruits and seeds, comparing relative composition and fruiting activity between forests, using bi‐monthly phenology surveys across 50 locations (October 2016–2019). We also compared fruit presence along walking transects within LEWS's primary forest and the mixed‐use mosaic in Iban territories. We found forests within and adjacent to LEWS shared similar composition, synchrony, and extended periods of fruit scarcity. Mixed‐use mosaic bordering pulau provided more consistent fruits, however, due largely to an invasive tree (Bellucia pentamera). Our study suggests pulau retain diversity and synchrony of fruit resources comparable to primary forest, sustaining valuable habitat for wildlife within the greater mixed‐use mosaic of traditional Iban land management practices. These findings are important for understanding resources available to wildlife outside of protected areas, and how CF contribute to conserving biodiversity. [ABSTRACT FROM AUTHOR]

Abstract While reforestation is gaining momentum to moderate climate change via carbon sequestration, there is also an opportunity to use tree planting to confront declining global biodiversity. Where tree species vary in support of diversity, selecting appropriate species for planting could increase conservation effectiveness. We used a common garden experiment in Borneo using 24 native tree species to examine how variation among tree species in their support of beetle diversity is predicted by plant traits associated with “acquisitive” and “conservative” resource acquisition strategies. We evaluate three hypotheses: (1) beetle communities show fidelity to host identity as indicated by variation in abundance and diversity among tree species, (2) the leaf economic spectrum partially explains this variation as shown by beetle preferences for plant species that are predicted by plant traits, and (3) a small number of selected tree species can capture higher beetle species richness than a random tree species community. We found high variation among tree species in supporting three highly intercorrelated metrics of beetle communities: abundance, richness, and Shannon diversity. Variation in support of beetle communities was predicted by plant traits and varied by plant functional groups; within the dipterocarp family, high beetle diversity was predicted by conservative traits such as high wood density and slow growth, and in non‐dipterocarps by the acquisitive traits of high foliar K and rapid growth. Using species accumulation curves and extrapolation to twice the original sample size, we show that 48 tree species were not enough to reach asymptote levels of beetle richness. Nevertheless, species accumulation curves of the six tree species with the highest richness had steeper slopes and supported 33% higher richness than a random community of tree species. Reforestation projects concerned about conservation can benefit by identifying tree species with a disproportional capacity to support biodiversity based on plant traits.

• The endemic and critically endangered Vatica cauliflora was rediscovered in its native locality after 67 years. • Recently collected specimens with fruiting material enabled us to assign to the correct section. • We propose placement in section of Vatica as it shares equal, woody, and non-incrassate calyx lobes with other species in that section. • To support ex-situ conservation action, the fruit of V. cauliflora was collected and served in Bogor Botanic Gardens. Vatica cauliflora P.S.Ashton (Dipterocarpaceae) is an endemic and critically endangered tree found only in Kapuas Hulu, West Kalimantan, Indonesia. Due to a lack of fruiting specimens, the species has not been placed within one of the three sections currently recognised in the genus Vatica. In early 2020, this plant was recollected after 67 years. Voucher specimens were made of fruiting material, which enable us to assign this species to the correct section. Based on the equal, woody, and non-incrassate calyx lobes, the species is here placed in the sect. Vatica as these traits are shared with other species in that section. An updated morphological description alongside information on the habitat, vernacular names, and germination of the species are provided. [ABSTRACT FROM AUTHOR]

Ampelopsin C is a trimeric oligostilbene found in a limited number of plant families including Dipterocarpaceae. It shows anti-inflammatory effects in experimental models of psoriasis, induces apoptosis in HepG2 human hepatoma cell line, inhibits human glioma through inducing apoptosis and autophagy and other biological properties. The present work oversees a method for isolation of ampelopsin C from the methanol extract of Dipterocarpus semivestitus leaves. Different chromatographic techniques were employed, including an ultra-high performance liquid chromatography (UHPLC) analysis for method development, a preparative high performance liquid chromatography (prep-HPLC) for isolation and a recycling high performance liquid chromatography (r-HPLC) for purification of the compound. The isolated compound was identified and characterized using nuclear magnetic resonance (NMR). The spectroscopic data confirmed the structure of ampelopsin C. [ABSTRACT FROM AUTHOR]