Identifying the centres of origin of cultivated plants is important for conservation and sustainable management, since this is where these species tend to be most genetically diverse. This research seeks to determine the centre of origin and evolutionary history of nutmeg (Myristica fragrans; Myristicaceae), an emblematic spice tree species traditionally believed to originate from the Banda Islands, South Moluccas, Indonesia. We explored nutmeg's genetic diversity and structure across the Moluccas archipelago using nuclear microsatellite markers and whole plastid genome sequences. Two primary intra-specific genetic clusters were found: one in the North Moluccas (Ternate, Tidore and Bacan islands) with higher genetic diversity and another in the South Moluccas (Banda and Ambon islands), which exhibited signs of a recent bottleneck. Although the North Moluccas showed higher genetic diversity, approximate Bayesian computation analyses supported South Moluccas as the centre of origin of M. fragrans. The species migrated from South to North Moluccas during the late Pleistocene to early Holocene period and experienced a recent bottleneck in the South. These findings suggest a naturally driven distribution influenced by migration and past climate changes. Human activities have further shaped these patterns, offering insights for developing targeted conservation strategies for nutmeg based on its genetic diversity.

Architectural analysis provides a powerful analytical framework for understanding the ontogenetic trajectories of tree species and their adaptive responses to environmental constraints. Despite their ecological, economic, and cultural importance in West African agroforestry systems, the architectural development of Khaya senegalensis (Desr.) A. Juss. (Meliaceae) and Pterocarpus erinaceus Poir. (Fabaceae), two overexploited taxa classified as Vulnerable on the IUCN Red List, had never been formally described. This study presents the first complete characterization of their architectural development, from the seedling stage to senescence, based on architectural and retrospective analyses conducted on 360 individuals per species across seven localities along a south-north bioclimatic gradient in Côte d'Ivoire, covering contrasting vegetation zones ranging from dense humid forest to dry Sudanian savanna. Both species display well-defined ontogenetic trajectories comprising four phases: juvenile establishment, architectural construction, reproductive transition, and crown restructuring associated with ageing. Distinct architectural models were identified: K. senegalensis conforms to Rauh's model, characterized by a monopodial orthotropic trunk with indefinite growth and rhythmic acrotonic branching; P. erinaceus follows Troll's model, in which the orthotropic trunk progressively gives rise to a sympodial plagiotropic system with mixed terminal and lateral flowering. Architectural units, defined as the minimal structural organization enabling a species to reach reproductive maturity, were established at the adult stage: that of K. senegalensis comprises four axis categories and five branching orders, while that of P. erinaceus comprises three axis categories and up to six branching orders in old trees. Significant variation in growth-unit morphology among habitats and localities ( P<0.05 ) revealed the architectural plasticity of both species in response to ecological gradients. The calculated Favourable Development indices ( FDi ) identified Bouaké and Katiola as optimal zones for K. senegalensis , and Bouaké and Toumodi for P. erinaceus , providing objective spatial criteria for reforestation planning. These findings demonstrate that architectural traits are robust indicators of development, adaptive strategies, and crown functioning. By linking structural organization to productivity, resilience, and regeneration potential, this study provides a scientific basis for integrating architectural analysis into reforestation programmes, sustainable forest management, and the design of agroforestry systems for threatened African tree species facing growing climatic and anthropogenic pressures. Complementary regression analyses further showed that phytomer number, rather than internode elongation, primarily governs growth-unit length in both species, and that growth unit diameter scales positively with growth unit length; a multivariate analysis of variance (MANOVA) confirmed that ontogenetic stage and locality, but not habitat alone, robustly structure growth-unit morphology.

Canarium schweinfurthii (Burseraceae), commonly known as African Elemi, is a culturally and economically significant food tree in tropical Africa, valued for its fruits, medicinal uses, and high-quality timber. Despite its importance and wide distribution, no prior studies have explored the species’ genetic diversity, a crucial component for its conservation and sustainable management. This study aims to develop nuclear microsatellite (SSR) markers and use them to provide the first insights into the spatial genetic structure of C. schweinfurthii populations across West and Central Africa. We selected 48 primer pairs from a large SSR database and tested them for amplification and polymorphism. Thirteen polymorphic loci were retained and used to genotype 98 individuals sampled from four populations in three African countries (Cameroon, Côte d’Ivoire, and Burkina Faso), including both wild and cultivated trees. The 13 markers were highly polymorphic with a number of alleles per locus varying from 6 to 29 (average of 16.54 ± 7.81). The mean FIS coefficient per population was 0.165 ± 0.070. The genetic differentiation (FST) was the lowest between geographically neighboring populations (between the population from Côte d’Ivoire and Burkina Faso, and between the two populations from Cameroon) and was the highest between West African populations and Central African populations. We have not observed any reduction in genetic diversity between the wild and cultivated populations in Cameroon. These new SSR markers provide effective tools to study gene flow and population structure in C. schweinfurthii. The observed genetic patterns offer a foundation for future genomic studies and support the development of targeted conservation strategies for this emblematic African tree. Thirteen novel SSR markers were developed for Canarium schweinfurthii, a key African fruit tree species. High genetic diversity was revealed in both wild and cultivated populations across West and Central Africa. A clear genetic structure separates Upper and Lower Guinean populations, suggesting historical fragmentation. Cultivated populations maintain significant diversity, but show signs of inbreeding due to local management. New SSR tools enable future studies on gene flow, domestication and conservation of C. schweinfurthii.

Since their inception, the French academic organizations dedicated to agricultural research have developed plant collections in genebanks, often within a public–private framework, to support the study of plant traits and the development of new improved varieties. In addition, since the 2000s, a centre for genomic resources has also been established in France. Over the last 20 years, this decentralized system, consisting of the academic genebanks and the centre for genomic resources, has been supported by a national coordination structure. The objectives were to align the network activities with the framework proposed by the Organisation for Economic Co-operation and Development (OECD) for Biological Resource Centres and to foster collaboration with other national stakeholders involved in the conservation and characterization of plant genetic resources (PGR). In 2015, the network was named BRC4Plants and become part of the French National Research Infrastructure RARe (www.agrobrc-rare.org), supported by the French Ministry of Research. This paper describes BRC4Plants, its users, services and cross-cutting activities. We also highlight its relations with its national and international stakeholders involved in the conservation and characterization of PGRs. BRC4Plants aims to be a key player in addressing societal and research challenges regarding agroecology, climate change mitigation and healthy food systems.

Canarium schweinfurthii is an endemic species in tropical Africa indicative of ancient sites of human occupation. A better understanding of the dynamics of sociocultural and traditional ecological knowledge surrounding this species could contribute to the development of strategies for its sustainable management and conservation in situ and ex situ. To analyze its uses and management practices across forest and savanna zones in Cameroon, focus groups (N = 6) and semi-structured interviews (N = 300) were conducted with seven ethnic groups from six sites. The analysis of the interviews revealed significant variations in the uses and management practices of the species among respondents from different ethnic groups living in the savanna and forest zones, as well as among those from different ethnic groups within the forest. In the savanna, where the fruit is valued for food and trade, participants used non-destructive harvesting practices, preserving the species through maintenance and/or transplantation of wildings. Meanwhile, in forest areas, resin and bark harvesting were carried out regularly and unsustainably, potentially contributing to the degradation of natural stands. Moreover, respondents were unfamiliar with the use of the fruit, and no tree planting or maintenance initiatives were reported in the forest. These results highlight the need to promote participatory domestication as a sustainable management strategy for Canarium schweinfurthii. Such efforts aim to encourage planting initiatives in the savanna, while raising awareness for its conservation among communities in the forest.

Understanding the distribution of genetic diversity of endemic food tree species holds significant importance for conservation planning and the formulation of effective management strategies. Natural and anthropogenic factors can influence species geographic range and distribution of genetic diversity. Here, we tested the relative influence of barriers to gene flow (rivers, mountains and past climate change) and recent human activities on the evolutionary history of an endemic species from Fakfak district, Papua Island, Myristica argentea Warb (Myristicaceae), better known as Papuan nutmeg. Myristica argentea is a spice tree species used by local populations since centuries/millennia. The species has been introduced in other locations from the region. Fourteen microsatellite markers (nSSRs), whole chloroplast (cp) genome, and nuclear-targeted sequence genes (nrDNA sequence) were used to characterize the genetic diversity, population structure, and demographic history of the species across its distribution range (native and introduced populations). We found that native populations of the species in Fakfak present higher levels of genetic diversity than introduced populations. We further detected the presence of a moderate genetic structure (FST = 0.143), and the presence of three intraspecific genetic clusters. Additionally, our findings indicate that population fragmentation within the native range of the species in Fakfak, may have been influenced by the presence of riparian networks, mountain ranges and by Pleistocene climatic fluctuations. Our results suggest that all introduced populations were sourced mainly from the native population of Raduria, in the South of Fakfak region. Given the population genetic variation across the ranges of Papuan nutmeg, management plans should not treat them as single populations, but rather consider the broader genetic diversity within its range. ### Competing Interest Statement The authors have declared no competing interest.

The identification of cultivated plant centers of origin is of growing interest since the pioneering work of Nikolaï Vavilov. Cultivated species generally show a high level of genetic diversity in their center of origin, thus identifying these areas would have important implications for the conservation and sustainable management of their genetic resources. We aim to identify the center of origin and to infer recent evolutionary history of one of the most emblematic spice tree species ¬¬– nutmeg (Myristica fragrans; Myristicaceae). The species is thought to originate from the Banda islands (Southern Moluccas archipelago, Indonesia), but this has never been confirmed. We characterized the genetic diversity of this species across the Moluccas archipelago using recently developed nuclear microsatellites markers and whole plastid genome sequences. We found two main intra-specific genetic clusters: one in South Moluccas (Banda and Ambon islands) and another in North Moluccas (Ternate, Tidore and Bacan islands). The latter cluster showed higher genetic diversity than the South Moluccas cluster. We then inferred the demographic history of nutmeg and evaluated different evolutionary scenarios using Approximate Bayesian Computation (ABC) analyses. Populations from South Moluccas show patterns of a recent bottleneck, whereas North Molucca populations did not. Moreover, South Moluccas populations are inferred as ancestral, with subsequent population migration to the North Moluccas during the late Pleistocene to early Holocene period. These results have strong implications for conservation strategies of nutmeg.

Background and aims – We developed a new set of nuclear microsatellite markers for Cola acuminata (Malvaceae), an important African food tree species commonly known as the kola nut. Probably originating from the tropical rainforests of the Congo Basin, C. acuminata is widely cultivated in the humid savannahs of the region where its nuts are sold throughout Central and West Africa for their stimulant properties. Nuclear microsatellite markers (SSRs) are well suited for assessing the genetic diversity and population structure of plant species due to their high variability. Material and methods – Leaf samples were collected from 84 C. acuminata cultivated individuals across three sites in Cameroon, two in the savannah zone, one in the forest zone. SSR markers were developed by sequencing genomic DNA from two individuals using an Illumina HiSeq platform. Genetic diversity was assessed based on 14 SSR markers genotyped in 84 individuals, and marker transferability to the closely related species Cola nitida was tested. Key results – Forty-eight new microsatellite loci were developed, of which 14 were polymorphic in C. acuminata. The results demonstrated a high level of genetic diversity with the presence of two to 33 alleles per locus (with an average of 14.14) across the three sites. The transferability of these markers was confirmed with 13 out of the 14 SSRs successfully amplifying in the closely related species, Cola nitida. Conclusion – These newly developed SSRs will be useful for assessing genetic diversity, genetic differentiation, and gene flow patterns of C. acuminata in the tropical forests of Central Africa. Preliminary results suggest genetic similarity between the two savannah sites. However, these two sites were significantly differentiated from the site in the forest zone. This suggests that the propagation material introduced in the savannah zone did not originate from the forest in southern Cameroon.

Correction to: Genetic Resources https://doi.org/10.46265/genresj.ASZO2413; published online 04 March 2025 Incorrect affiliation In the published article, there was an error in the affiliations of Nilda Paulo-de-la-Réberdiere. Instead of “[h,g]”, it should have been “[g,h]”. Incorrect author names In the published article, two author names were incorrectly written: - Cristophe Jenny (correct: Christophe Jenny) - Françoise Nuissier (correct: Franciane Nuissier) Error in Table 1 In the published article, there was an error in Table 1: - [Perennial plants in Guyana (PPG)]: Instead of “Guyana”, it should have been “French Guiana”. - [Coffea spp., Theobroma spp., Hevea spp., Dalbergia spp.]: Instead of Dalbergia, it should have been Aniba rosodora. The authors apologize for these errors and state that they do not affect the scientific conclusions of the article in any way.The PDF and HTML versions of the original article have been updated and are available at https://doi.org/10.46265/genresj.ASZO2413

The architectural plasticity forms observed in trees is a result of meristem functioning, which generates new organs and branches, and adjusts growth processes in response to heterogeneous climatic adaptations that affect biomass allocation. Analyzing this plasticity should enable the selection of adapted individuals for optimizing successful cropping systems. Mahogany tree (Khaya senegalensis) is a rhythmically growing indigenous agroforestry tree that is heavily exploited for its multiple uses. Understanding its growth characteristics, as well as the complexity of its structure (randomness, rhythmicity, etc. of Mahogany tree), could facilitate its conservation and sustainable management. This study aims to model the architecture and physiology of young mahogany trees based on field data using an organ-level structural-functional model called 'GreenLab', which is founded on source-sink relationships. Ninety trees aged 6, 12, and 24 months were measured in the field. Development was calculated using a dual-scale automaton based on the Monte Carlo process, while biomass production and its distribution to different plant organs (source and sink) were calibrated using Pressler's law using Markov chains. Meristematic activity laws, combined with organ sinks (D: Demand), photosynthesis (Q: Supply), and organic series (Q/D: Trophic pressure), were employed to simulate individual architecture. The results demonstrate that the model realistically and flexibly describes topological development and replicates biomass production and allocation processes for rhythmically growing trees. This model will enable the identification of mahogany ideotypes suited for enhancing agroforestry cropping systems based on this species and several other threatened species. These findings introduce and thus lay the groundwork for a computational plant model tailored to the needs of agroforestry from a novel perspective, offering new avenues for agronomic and forestry applications in West Africa and Cote d'Ivoire.

Dacryodes edulis, known as the African plum tree, is an important indigenous fruit species in Central Africa that has long been used by humans. Wild individuals of this species are found in forests, whereas cultivated trees are distributed in agroforests and homegardens. As knowledge is sparse regarding local knowledge and uses of wild African plum trees this study fills this gap by collecting and analyzing the knowledge of different ethnic groups in Cameroon and Gabon. Focus groups, field visits, and individual surveys were conducted with 243 participants from the Baka, Fang, Nzime, Bassa, and Obamba ethnic groups. Several vernacular names were reported for wild African plum trees, generally related to their morphology and environment. Fruit size was the most common morphological trait used to identify wild individuals. This study recorded six tree parts and five different use categories, with food being the most common use, followed by medicine. Wild African plum trees have a socio-cultural importance for the Baka who still depend on forests for their livelihood. However, wild trees are not usually included in conservation strategies; hence, the wild form of this species is at risk due to poor regeneration success without human intervention. Recommended measures for sustainable management and conservation of wild individuals of this species are discussed.

Societal Impact Statement Crop seed exchange networks, shaped by social dynamics, strongly influence the organization and breadth of plant diversity in human‐managed environments. Integrating an urban and market perspective, this study explores the diversity dynamics of a socio‐economically important Central African fruit tree species, the African plum tree. Tree owners in urban, peri‐urban and rural sites use seeds from different origins as their main propagation material, leading to locational variations in genetic diversity and structure. This analysis contributes toward building a framework to inform the research agenda of cultivated African fruit trees, by highlighting the important role of urban centers in safeguarding crop genetic resources. Summary Biocultural factors constrain the dynamics of crop species diversity. Here, we considered different aspects of the social, spatial and temporal dynamics of morphological and genetic diversity in a multi‐purpose perennial crop, the African plum tree ( Dacryodes edulis ). We assessed (i) how seed exchange networks were organized along urbanization gradients, and how they influenced the distribution of species diversity; (ii) the temporal dynamic of seed exchange network by characterizing species genetic diversity through time. To do so, the study was carried out in Cameroon, where we focused on three urbanization gradients, covering urban, peri‐urban and rural areas, corresponding to three different ethnic groups (Bamileke, Bassa, Beti). We combined interviews with tree owners and nuclear microsatellite‐based genetic analyses. Tree owners from urban and peri‐urban sites primarily used distant seed sources, acquired in the market or from their village of origin, as propagation material, whereas tree owners in rural sites relied primarily on village‐level seeds. In turn, genetic diversity was not evenly distributed, with rural sites exhibiting their own genetic clusters. On the contrary, the genetic diversity of urban sites was enhanced by extensive human‐mediated seed flows. Looking at trees from different age classes, we found that genetic diversity was stable over time. Overall, this first attempt to combine different levels of diversity for African plum trees in commercially connected areas expands the scope for in situ intraspecific conservation by highlighting the contribution of urbanized areas.

Mangosteen (Garcinia mangostana var. mangostana) is a dioecious and agamospermous cultivated fruit tree. It has two recognised hypothetical wild ancestors, Garcinia mangostana var. malaccensis and G. mangostana var. borneensis, distributed in the lowland dipterocarp-dominated forests of Sumatra, the Malay Peninsula, and Borneo. The highly similar morphological characters between the cultivated and wild varieties have posed challenges in identification. Additionally, Garcinia penangiana is often mistaken for G. mangostana var. malaccensis, and G. venulosa is regarded as morphologically similar to G. mangostana var. borneensis. In the present study, we conducted morphometric analyses of Garcinia mangostana var. mangostana, G. mangostana var. borneensis, G. mangostana var. malaccensis, G. penangiana and G. venulosa. We assessed the efficacy of morphological characters in combination (vegetative–male flowers–female flowers) in distinguishing the taxa as recognised in the current taxonomy. In our morphometric analyses, we found that Garcinia penangiana and G. venulosa are well delimited and congruent with their current taxonomic designations. A combination of vegetative and male-flower characters provided the most definitive delimitation. We recovered the specific coherence of Garcinia mangostana, but the infraspecific delineations of G. mangostana var. mangostana, G. mangostana var. borneensis and G. mangostana var. malaccensis are not supported.

Phylogeographic studies on widespread rainforest species from West and Central Africa often reveal genetic discontinuities. These discontinuities can originate from past barriers to gene flow resulting from long-lasting population fragmentation during glacial periods, according to the forest refuge hypothesis. This study 69 nuclear SNPs, 13 plastid SNPs, and 24 mitochondrial SNPs to characterized the distribution of genetic diversity in 377 individuals of the widespread tropical tree Khaya ivorensis, in western and central African evergreen forests. Two very well-differentiated nuclear genetic clusters (FST = 0.28) are located respectively in West and Central Africa. The gradual transition of allele frequencies between the clusters across a broad geographic area going from Cameroon to Nigeria accords with the recognition of a single species, although we show an incipient divergence that could eventually lead to the separation of two taxa. The two clusters have similar genetic diversity at nuclear SNPs. However, the cytoplasmic data revealed high haplotypic diversity and numerous endemic haplotypes in Central Africa, and only one widespread haplotype in West Africa, suggesting an ancient colonization of West Africa from Central Africa. The genetic diversity inside and outside putative forest refugia (Anhuf et al., Palaeogeogr Palaeoclimatol Palaeoecol 239:510–527, 2006) does not differ significantly in either genetic cluster. Hence, we cannot confirm that forest refugia played a particular role in the pattern of distribution of genetic diversity in K. ivorensis. Owing to the high haplotypic diversity of their populations, Central Africa, especially Gabon, constitutes a priority area for the conservation of the genetic diversity of K. ivorensis.

Abstract Mangifera casturi Kosterm is one of the endemic fruits from South Kalimantan. It belongs to the genus Mangifera of the Anacardiaceae family. This study aimed to analyze the genetic relationship of Mangifera casturi from South Kalimantan and Riau using microsatellite markers. Fourteen Mangifera casturi accessions were amplified using fourteen microsatellite loci, and the data produced was utilized to evaluate the genetic relationship. DNA amplification using the multiplex PCR method with fluorescence-labeled dyes on the forward primer will be detected using capillary electrophoresis. Forty-two alleles were obtained from the fourteen loci, averaging three per locus. The observed heterozygosity value (Ho) is 0.24, which is lower than the expected heterozygosity value (He), with an average of 0.48. The fourteen-microsatellite fixation index (FIS) loci ranged between –0.876 and 1. The average Polymorphic information content (PIC) value is 0.39, with the highest found in MC58089 loci (0.65), indicating the SSR marker loci are informative for revealing genetic diversity. The phylogenetic analysis using the neighbor-joining method was constructed into four groups. Kasturi mango from Riau is closely related to Pelipisan and Cuban cultivars from South Kalimantan.

Community Forest Management in the Maya Biosphere Reserve (MBR; Petén, Guatemala) has been recognized internationally for yielding forest conservation and socioeconomic benefits. However, the effect of current timber harvesting practices on the genetic diversity of timber species populations has not previously been documented. This study assessed the effects of timber harvesting on the genetic diversity and viability of regeneration of the most commercially important timber species in the MBR: big-leaf mahogany (Swietenia macrophylla King). Trees and seeds were sampled for two consecutive years in two Forest Management Units of the Multiple Use Zone (MUZ) of the MBR: Cruce a la Colorada and Carmelita. We correlated genetic diversity parameters (as measured using nuclear microsatellites) with seed germination percentages and compared genetic diversity of adults and seeds in stands that had been affected by timber harvesting and those that had not. We found a significant correlation between seed germination percentages (81–83%) and observed heterozygosity (rho=0.27), confirming that genetic diversity is important to regeneration success. No significant differences were found in allelic richness (AR), expected and observed heterozygosity (HE and HO), or inbreeding (FIS), between adults and seeds in harvested vs. undisturbed stands; or before and after timber harvesting. We found low inbreeding levels (FIS=0.040–0.094), low biparental inbreeding (0–0.01), and high outcrossing rates (0.925–0.970) in the populations of S. macrophylla analyzed. Our study therefore provides evidence that genetic diversity in big-leaf mahogany populations was not diminished by one cutting cycle under current practices of community forest management in the MUZ of the MBR.

Non-timber forest products (NTFPs) are important components of rural people’s livelihood, being used notably for food and medicine. Given their socio-economic importance, NTFP species are often integrated in farmers’ fields using wild seed material from adjacent forests. In sub-Saharan Africa, the evolutionary history, and more specifically, the cultivation history of these species (geographical origin, dating), is still largely unknown. This study focuses on an African medicinal tree species, originating from the Guineo-Congolian rain forests and commonly known as the bitter kola tree ( Garcinia kola , Clusiaceae). We estimated species genome size and chromosome number. We developed eleven highly polymorphic nuclear microsatellite markers and used seven of them to characterize patterns of distribution of genetic diversity within populations of G. kola in the forest (161 wild individuals coming from nine different populations from Cameroon, Gabon, and the Republic of Congo) and on-farm (82 cultivated individuals from five populations from Cameroon). The species is most probably hexaploid, with a relatively large genome size (2C = 25.5 to 28.5 picogram) and ca. 170 chromosomes. Three intra-specific gene pools were observed along a north–south axis within wild populations. This genetic differentiation pattern presents some similarities with patterns already observed in other tree species from the region, suggesting that a common factor, potentially past-climatic oscillations, has affected the demography of forest trees in the same way. Cultivated populations were not spatially structured, and the genetic differentiation between wild and cultivated populations was low ( G ST = 0.017). The cultivation history of the species was difficult to interpret. It is actually unclear if cultivated populations from Cameroon are derived from wild Cameroonian populations or if they originate from wild populations of West African countries, notably Nigeria.

Abstract Mangosteen (Garcinia mangostana var. mangostana) is a popular tropical fruit, yet many aspects of its biology and evolutionary history are little known. Its origin remains contentious, although recent findings suggest G. mangostana L. var. malaccensis (Hook. f.) Nazre (synonym: G. malaccensis Hook. f.) as the sole progenitor. We review hypotheses on the origin of mangosteen and clarify points that have been affected by errors of fact and interpretation. The narrow focus and lack of detail in published results make their interpretation difficult. When possible, we support our interpretations with field observations and examination of herbarium specimens. We outline the main biological traits (e.g., dioecy, facultative apomixis, and polyploidy) of mangosteen and its wild relatives to infer traits that might have evolved during domestication of mangosteen. We find no clear indication that apomixis and polyploidy evolved during domestication. Polyploidy is known in the wild relatives, but apomixis has not yet been demonstrated. Also, we propose a testable new evolutionary‐ecological framework that we call “Forest‐Dusun Interface” to infer processes in the origin of mangosteen. Dusun (Malay) refers to subsistence orchards in this context. Lastly, we propose future studies to address identified knowledge gaps.