With more than two billion people suffering from malnutrition and diets homogenizing globally, it is vital to identify and conserve nutrient-rich species that may contribute to improving food ...security and diversifying diets. Of the approximately 390,000 vascular plant species known to science, thousands have been reported to be edible, yet their nutritional content remains poorly characterized. Here we use phylogenetic information to identify plants with the greatest potential to support strategies alleviating B-vitamin deficiencies. We predict the B-vitamin profiles of >6,400 edible plants lacking nutritional data and identify 1,044 species as promising key sources of B vitamins. Several of these source species should become conservation priorities, as 63 (6%) are threatened in the wild and 272 (26%) are absent from seed banks. Moreover, many of these conservation-priority source species overlap with hotspots of malnutrition, highlighting the need for safeguarding strategies to ensure that edible plant diversity remains a reservoir of nutrition for future generations, particularly in countries needing it most. Although by no means a silver bullet to tackling malnutrition, conserving a diverse portfolio of edible plants, unravelling their nutritional potentials, and promoting their sustainable use are essential strategies to enhance global nutritional resilience.
Summary
Angiosperms, which inhabit diverse environments across all continents, exhibit significant variation in genome sizes, making them an excellent model system for examining hypotheses about the ...global distribution of genome size. These include the previously proposed large genome constraint, mutational hazard, polyploidy‐mediated, and climate‐mediated hypotheses.
We compiled the largest genome size dataset to date, encompassing 16 017 (> 5% of known) angiosperm species, and analyzed genome size distribution using a comprehensive geographic distribution dataset for all angiosperms.
We observed that angiosperms with large range sizes generally had small genomes, supporting the large genome constraint hypothesis. Climate was shown to exert a strong influence on genome size distribution along the global latitudinal gradient, while the frequency of polyploidy and the type of growth form had negligible effects. In contrast to the unimodal patterns along the global latitudinal gradient shown by plant size traits and polyploid proportions, the increase in angiosperm genome size from the equator to 40–50°N/S is probably mediated by different (mostly climatic) mechanisms than the decrease in genome sizes observed from 40 to 50°N northward.
Our analysis suggests that the global distribution of genome sizes in angiosperms is mainly shaped by climatically mediated purifying selection, genetic drift, relaxed selection, and environmental filtering.
The five Mediterranean regions of the world comprise almost 50,000 plant species (ca 20% of the known vascular plants) despite accounting for less than 5% of the world's land surface. The ecology and ...evolutionary history of two of these regions, the Cape Floristic Region and the Mediterranean Basin, have been extensively investigated, but there have been few studies aimed at understanding the historical relationships between them. Here, we examine the biogeographic and diversification processes that shaped the evolution of plant diversity in the Cape and the Mediterranean Basin using a large plastid data set for the geophyte family Hyacinthaceae (comprising ca. 25% of the total diversity of the group), a group found mainly throughout Africa and Eurasia. Hyacinthaceae is a predominant group in the Cape and the Mediterranean Basin both in terms of number of species and their morphological and ecological variability. Using state-of-the-art methods in biogeography and diversification, we found that the Old World members of the family originated in sub-Saharan Africa at the Paleocene-Eocene boundary and that the two Mediterranean regions both have high diversification rates, but contrasting biogeographic histories. While the Cape diversity has been greatly influenced by its relationship with sub-Saharan Africa throughout the history of the family, the Mediterranean Basin had no connection with the latter after the onset of the Mediterranean climate in the region and the aridification of the Sahara. The Mediterranean Basin subsequently contributed significantly to the diversity of neighbouring areas, especially Northern Europe and the Middle East, whereas the Cape can be seen as a biogeographical cul-de-sac, with only a few dispersals toward sub-Saharan Africa. The understanding of the evolutionary history of these two important repositories of biodiversity would benefit from the application of the framework developed here to other groups of plants present in the two regions.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Fabales is a cosmopolitan angiosperm order that consists of four families: Leguminosae (Fabaceae), Polygalaceae, Surianaceae, and Quillajaceae. Despite the great interest in this group, a convincing ...phylogeny of the order is still not available. Therefore, the aim of this study was to explicitly test for possible long branch attraction (LBA) problems within Fabales for the first time, and determine whether low tree stemminess and unequal branch lengths could worsen this problem. Supermatrix analysis of Fabales was carried out using previously published plastid matK, trnL, rbcL, and newly sequenced nuclear sqd1 regions for 678 taxa in total, including 43 outgroup taxa from families of Fabidae. We employed additional analyses, such as simulations, network analyses, sampling different outgroup taxa (random or real), removing fast evolving sites and fast evolving taxa, and molecular clock rooting, to identify both LBA and (or) rooting problems. These analyses clearly show that the Fabales phylogeny has been influenced by the sampling of outgroup taxa, but not LBA. However, network analyses show that even though it is weak, there is a consistent phylogenetic signal among the rapidly radiated Fabales families, which can be traced by further analyses. While, molecular clock rooting analysis yielded a (Leguminosae(Polygalaceae(Surianaceae+Quillajaceae))) topology with strong support for the first time here, supermatrix analyses yielded a ((Leguminosae+Polygalaceae)(Surianaceae+Quillajaceae)) with low-moderate support.
Celotno besedilo
Dostopno za:
BF, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Although vanilla is one of the most popular flavours in the world, there is still uncertainty concerning the native distribution of the species that produces it, Vanilla planifolia. To ...circumscribe the native geographical extent of this economically important species more precisely, we propose a new landscape-based approach to incorporate information from open-source databases and validate occurrences. In this approach, we include metrics to account for habitat suitability and population sustainability in terms of the biotic (co-occurrence of pollinators and dispersers) and abiotic (habitat quality) factors limiting plant distributions. To further validate occurrences within the resulting distribution, we compare the presence of morphologically similar wild relatives, assess the heterogeneity of ecological niches and verify the correct identification of herbarium specimens. Results from this approach suggest that V. planifolia has a larger geographical distribution than previously recognized; we hypothesize that populations naturally dispersed from Mesoamerica and became established in South America (with a south-eastern limit in Brazil). The recognition of an improved estimate of the distribution of this species will increase the accuracy of predictive models, promote further species circumscription, improve the efficacy of conservation strategies, and help to ensure the sustainability of a valuable, sought-after spice.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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•The Brownea clade diversified gradually, following the ‘museum’ model.•The Brownea clade originated in the Eocene, and diversified throughout the Neogene.•The clade diversified ...mainly in Amazonia, with subsequent migrations across the Neotropics.
The flora of the Neotropics is unmatched in its diversity, however the mechanisms by which diversity has accumulated are debated and largely unclear. The Brownea clade (Leguminosae) is a characteristic component of the Neotropical flora, and the species within it are diverse in their floral morphology, attracting a wide variety of pollinators. This investigation aimed to estimate species divergence times and infer relationships within the group, in order to test whether the Brownea clade followed the ‘cradle’ or ‘museum’ model of diversification, i.e. whether species evolved rapidly over a short time period, or gradually over many millions of years. We also aimed to trace the spatio-temporal evolution of the clade by estimating ancestral biogeographical patterns in the group. We used BEAST to build a dated phylogeny of 73 Brownea clade species using three molecular markers (ITS, trnK and psbA-trnH), resulting in well-resolved phylogenetic relationships within the clade, as well as robust divergence time estimates from which we inferred diversification rates and ancestral biogeography. Our analyses revealed an Eocene origin for the group, after which the majority of diversification happened in Amazonia during the Miocene, most likely concurrent with climatic and geological changes caused by the rise of the Andes. We found no shifts in diversification rate over time, suggesting a gradual accumulation of lineages with low extinction rates. These results may help to understand why Amazonia is host to the highest diversity of tree species on Earth.
Premise
The carrot family (Apiaceae) comprises 466 genera, which include many well‐known crops (e.g., aniseed, caraway, carrots, celery, coriander, cumin, dill, fennel, parsley, and parsnips). ...Higher‐level phylogenetic relationships among subfamilies, tribes, and other major clades of Apiaceae are not fully resolved. This study aims to address this important knowledge gap.
Methods
Target sequence capture with the universal Angiosperms353 probe set was used to examine phylogenetic relationships in 234 genera of Apiaceae, representing all four currently recognized subfamilies (Apioideae, Azorelloideae, Mackinlayoideae, and Saniculoideae). Recovered nuclear genes were analyzed using both multispecies coalescent and concatenation approaches.
Results
We recovered hundreds of nuclear genes even from old and poor‐quality herbarium specimens. Of particular note, we placed with strong support three incertae sedis genera (Platysace, Klotzchia, and Hermas); all three occupy isolated positions, with Platysace resolved as sister to all remaining Apiaceae. We placed nine genera (Apodicarpum, Bonannia, Grafia, Haplosciadium, Microsciadium, Physotrichia, Ptychotis, Tricholaser, Xatardia) that have never previously been included in any molecular phylogenetic study.
Conclusions
We provide support for the maintenance of the four existing subfamilies of Apiaceae, while recognizing that Hermas, Klotzschia, and the Platysace clade may each need to be accommodated in additional subfamilies (pending improved sampling). The placement of the currently apioid genus Phlyctidocarpa can be accommodated by the expansion of subfamily Saniculoideae, although adequate morphological synapomorphies for this grouping are yet to be defined. This is the first phylogenetic study of the Apiaceae using high‐throughput sequencing methods and represents an unprecedented evolutionary framework for the group.
Aim: Recently developed parametric methods in historical biogeography allow researchers to integrate temporal and palaeogeographical information into the reconstruction of biogeographical scenarios, ...thus overcoming a known bias of parsimony-based approaches. Here, we compare a parametric method, dispersalextinction-cladogenesis (DEC), against a parsimony-based method, dispersalvicariance analysis (DIVA), which does not incorporate branch lengths but accounts for phylogenetic uncertainty through a Bayesian empirical approach (Bayes-DIVA). We analyse the benefits and limitations of each method using the cosmopolitan plant family Sapindaceae as a case study. Location: World-wide. Methods: Phylogenetic relationships were estimated by Bayesian inference on a large dataset representing generic diversity within Sapindaceae. Lineage divergence times were estimated by penalized likelihood over a sample of trees from the posterior distribution of the phylogeny to account for dating uncertainty in biogeographical reconstructions. We compared biogeographical scenarios between Bayes-DIVA and two different DEC models: one with no geological constraints and another that employed a stratified palaeogeographical model in which dispersal rates were scaled according to area connectivity across four time slices, reflecting the changing continental configuration over the last 110 million years. Results: Despite differences in the underlying biogeographical model, Bayes-DIVA and DEC inferred similar biogeographical scenarios. The main differences were: (1) in the timing of dispersal events -which in Bayes-DIVA sometimes conflicts with palaeogeographical information, and (2) in the lower frequency of terminal dispersal events inferred by DEC. Uncertainty in divergence time estimations influenced both the inference of ancestral ranges and the decisiveness with which an area can be assigned to a node. Main conclusions: By considering lineage divergence times, the DEC method gives more accurate reconstructions that are in agreement with palaeogeographical evidence. In contrast, Bayes-DIVA showed the highest decisiveness in unequivocally reconstructing ancestral ranges, probably reflecting its ability to integrate phylogenetic uncertainty. Care should be taken in defining the palaeogeographical model in DEC because of the possibility of overestimating the frequency of extinction events, or of inferring ancestral ranges that are outside the extant species ranges, owing to dispersal constraints enforced by the model. The wide-spanning spatial and temporal model proposed here could prove useful for testing large-scale biogeographical patterns in plants.
Hybridization has the potential to generate or homogenize biodiversity and is a particularly common phenomenon in plants, with an estimated 25% of plant species undergoing interspecific gene flow. ...However, hybridization in Amazonia's megadiverse tree flora was assumed to be extremely rare despite extensive sympatry between closely related species, and its role in diversification remains enigmatic because it has not yet been examined empirically. Using members of a dominant Amazonian tree family (Brownea, Fabaceae) as a model to address this knowledge gap, our study recovered extensive evidence of hybridization among multiple lineages across phylogenetic scales. More specifically, using targeted sequence capture our results uncovered several historical introgression events between Brownea lineages and indicated that gene tree incongruence in Brownea is best explained by reticulation, rather than solely by incomplete lineage sorting. Furthermore, investigation of recent hybridization using ~19,000 ddRAD loci recovered a high degree of shared variation between two Brownea species that co‐occur in the Ecuadorian Amazon. Our analyses also showed that these sympatric lineages exhibit homogeneous rates of introgression among loci relative to the genome‐wide average, implying a lack of selection against hybrid genotypes and persistent hybridization. Our results demonstrate that gene flow between multiple Amazonian tree species has occurred across temporal scales, and contrasts with the prevailing view of hybridization's rarity in Amazonia. Overall, our results provide novel evidence that reticulate evolution influenced diversification in part of the Amazonian tree flora, which is the most diverse on Earth.
The data presented in this paper is supporting the research article “Reconstructing an historical pollination syndrome: keel flowers” (Aygören Uluer et al., 2022). We present a dataset containing ...information on number of species, geographic distribution, floral type (keeled or not), presence or absence of fused petals, floral symmetry, presence or absence of a pentamerous corolla (petals+petaloid sepals in Polygalaceae), androecium type, presence or absence of enclosed reproductive organs, presence or absence of three distinct petal types (petals+ petaloid sepals in Polygalaceae), flower size, corolla size (i.e., in open flower) and/or filament size (i.e., entire filament size particularly in subfamily Caesalpinioideae), flower colour, UV reflectance, habit, height, inflorescence type and inflorescence size for 758 Fabales genera. The information was obtained from hundreds of appropriate, previously published sources. This the largest morphological dataset constructed for Fabales to date, and the data presented in this article can be used for morphology, biogeography, ancestral state, ancestral area analyses of any Fabales clades.
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