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Yams (Dioscorea species) are an important food resource in Madagascar, where both cultivated winged yam (D. alata) and wild edible yams are consumed. However, there is limited knowledge on the nutrient composition of wild edible yams in Madagascar, and on how they compare with the cultivated winged yam. Therefore, in this study, nine wild edible yam species, one with two subspecies from Madagascar (D. bako, D. buckleyana, D. irodensis, D. maciba, D. orangeana, D. pteropoda, D. sambiranensis subsp. bardotiae and subsp. sambiranensis, D. seriflora, and Dioscorea species Ovy valiha), were analyzed for their nutrient composition, compared with cultivated D. alata. They include 6/6 of the most favored wild edible yam species in Madagascar. New nutrient composition data (protein, carbohydrate/starch, energy, lipid, β‐carotene, and minerals) are presented for these nine wild edible yam species. The results show that they contain comparable levels of lipids and starch to D. alata, but none are better sources of protein than D. alata. The results show that D. irodensis contains a significantly higher β‐carotene content when compared to all other edible yams analyzed, and that D. buckleyana, D. irodensis, and D. sambiranensis subsp. bardotiae have a higher calcium content than cultivated D. alata, while all nine wild edible yam species analyzed contain a higher iron content, compared to cultivated D. alata. The nutrient composition data presented could provide new incentives to conserve wild edible yams and inform on strategies to select Dioscorea species for sustainable cultivation and use, providing opportunities to enhance future food security in Madagascar. [ABSTRACT FROM AUTHOR]

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Clonal propagation enables favourable crop genotypes to be rapidly selected and multiplied. However, the absence of sexual propagation can lead to low genetic diversity and accumulation of deleterious mutations, which may eventually render crops less resilient to pathogens or environmental change. To better understand this trade‐off, we characterize the domestication and contemporary genetic diversity of Enset (Ensete ventricosum), an indigenous African relative of bananas (Musa) and a principal starch staple for 20 million Ethiopians. Wild enset reproduction occurs strictly by sexual outcrossing, but for cultivation, it is propagated clonally and associated with diversification and specialization into hundreds of named landraces. We applied tGBS sequencing to generate genome‐wide genotypes for 192 accessions from across enset's cultivated distribution, and surveyed 1340 farmers on enset agronomic traits. Overall, reduced heterozygosity in the domesticated lineage was consistent with a domestication bottleneck that retained 37% of wild diversity. However, an excess of putatively deleterious missense mutations at low frequency present as heterozygotes suggested an accumulation of mutational load in clonal domesticated lineages. Our evidence indicates that the major domesticated lineages initially arose through historic sexual recombination associated with a domestication bottleneck, followed by the amplification of favourable genotypes through an extended period of clonal propagation. Among domesticated lineages, we found a significant phylogenetic signal for multiple farmer‐identified food, nutrition and disease resistance traits and little evidence of contemporary recombination. The development of future‐climate adapted genotypes may require crop breeding, but outcrossing risks exposing deleterious alleles as homozygotes. This trade‐off may partly explain the ubiquity and persistence of clonal propagation over recent centuries of comparative climate stability. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Digitized molecular data are vital to numerous aspects of scientific research and genetic resource use. The Convention on Biological Diversity currently refers to this as "Digital Sequence Information" (DSI), a term not widely adopted by science and lacking a clear definition. There are concerns over the access to genetic resources and absence of benefit sharing by provider countries. Open access to DSI might exacerbate this, which is leading to increasing policy interventions and restricted access to genetic resources and DSI. We analyze current international debate and proposed solutions and provide case studies of DSI use producing tangible benefits for the provider countries and scientific research, demonstrating the importance of open access DSI to achieving conservation goals. Summary: Substantial advances in DNA sequencing over the last decades hold great potential to enhance food security and sustainable use of global biodiversity, benefiting the world's poorest people. Digital Sequence Information (DSI) plays a crucial role in catalyzing research applications that can contribute to international societal and biodiversity conservation targets. However, benefit sharing relating to DSI is difficult to identify and hindered by the lack of clear international governance and legislation, which in turn has led to a reluctance to make DSI publicly and freely available. Critically, no precise definition exists under the Convention on Biological Diversity (CBD), the Nagoya Protocol (NP), or the International Treaty for Plant Genetic Resources for Food and Agriculture (ITPGRFA). The key difference between DSI and biological resources, for which access and use are highly regulated under those frameworks, is that information is nonphysical. Information can be replicated and used without movement of, or access to, physical specimens. Thus, regulating the use of DSI is extremely challenging and remains controversial. Here, we review the regulation of DSI and the possible future steps by the international community, in the context of the benefit‐sharing obligations of the CBD, NP, and ITPGRFA. We highlight how multilateral agreements work in practice and are a solution to this impasse. We provide case studies demonstrating how the Royal Botanic Gardens, Kew, and its collaborators address the uncertainty surrounding the use of DSI, illustrating tangible and equitable benefits that have arisen from such use. We conclude that open access to DSI is needed for scientific research and international policy. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Enset is a staple food for over 20 million people via its starch‐rich corm and pseudostem, yet it is virtually unknown outside a narrow zone of cultivation in southern Ethiopia. Due to acculturation and urbanization coupled with climate change, emerging pests and the introduction of new crops, the extensive indigenous knowledge associated with this crop is in danger of being lost, imperilling the future food security and prosperity of millions of Ethiopians. Here, we synthesize the current state of enset ethnobotanical research, identifying key gaps and challenges, and provide a framework for further enset research to safeguard this important, but neglected, tropical crop. Summary Enset (Ensete ventricosum (Welw.) Cheesman) is the major starch staple of the Ethiopian Highlands, where its unique attributes enhance the food security of approximately 20 million people and have earned it the title "The Tree Against Hunger". Yet enset‐based agriculture is virtually unknown outside of its narrow zone of cultivation, despite growing wild across much of East and Southern Africa. Here, we review historical production data to show that the area of land under enset production in Ethiopia has reportedly increased 46% in two decades, whilst yield increased 12‐fold over the same period, making enset the second most produced crop species in Ethiopia—though we critically evaluate potential issues with these data. Furthermore, we address a major challenge in the development and wider cultivation of enset, by reviewing and synthesizing the complex and fragmented agronomic and ethnobotanic knowledge associated with this species; including farming systems, processing methods, products, medicinal uses and cultural importance. Finally, we provide a framework to improve the quality, consistency and comparability of data collected across culturally diverse enset‐based agricultural systems to enhanced sustainable use of this neglected starch staple. In conclusion, we discuss the challenges and opportunities for enset cultivation beyond its restricted distribution, and the regional food security potential it could afford smallholders elsewhere in Southern and East Africa. [ABSTRACT FROM AUTHOR]

Forest undergrowth plants are tightly connected with the shady and humid conditions that occur under the canopy of tropical forests. However, projected climatic changes, such as decreasing precipitation and increasing temperature, negatively affect understory environments by promoting light‐demanding and drought‐tolerant species. Therefore, we aimed to quantify the influence of climate change on the spatial distribution of three selected forest undergrowth plants, Dracaena Vand. ex L. species, D. afromontana Mildbr., D. camerooniana Baker, and D. surculosa Lindl., simultaneously creating the most comprehensive location database for these species to date. A total of 1,223 herbarium records originating from tropical Africa and derived from 93 herbarium collections worldwide have been gathered, validated, and entered into a database. Species‐specific Maxent species distribution models (SDMs) based on 11 bioclimatic variables from the WorldClim database were developed for the species. HadGEM2‐ES projections of bioclimatic variables in two contrasting representative concentration pathways (RCPs), RCP2.6 and RCP8.5, were used to quantify the changes in future potential species distribution. D. afromontana is mostly sensitive to temperature in the wettest month, and its potential geographical range is predicted to decrease (up to −63.7% at RCP8.5). Optimum conditions for D. camerooniana are low diurnal temperature range (6–8°C) and precipitation in the wettest season exceeding 750 mm. The extent of this species will also decrease, but not as drastically as that of D. afromontana. D. surculosa prefers high precipitation in the coldest months. Its potential habitat area is predicted to increase in the future and to expand toward the east. This study developed SDMs and estimated current and future (year 2050) potential distributions of the forest undergrowth Dracaena species. D. afromontana, naturally associated with mountainous plant communities, was the most sensitive to predicted climate warming. In contrast, D. surculosa was predicted to extend its geographical range, regardless of the climate change scenario. [ABSTRACT FROM AUTHOR]

Taxonomy provides a universal method to classify biodiversity at different scales locally and globally. Currently, existing taxonomic treatments are scattered, limiting their accessibility and utility. The Convention on Biological Diversity has responded to this challenge by setting the goal of compiling a World Flora Online (Global Strategy for Plant Conservation Target 1, 2011-2020). This can be done by aggregating electronically available information provided by each country, region or specialist group. Developing a Flora or a high-level monographic product requires time and input from a large pool of taxonomic specialists. Completing a Flora may be difficult to accomplish for phytodiverse countries, such as South Africa, if the 2020 target is to be met. Fortunately, a large number of taxonomic contributions and many electronic tools exist that can enhance progress. Where these are available, efforts have to be made to access and digitise the literature. Here we describe a pragmatic approach to developing an online Flora, involving taking f loristic information from multiple, previously published sources, digitising the legacy literature where needed and aggregating the required information into a single portal. South Africa is committed to producing an online Flora (the e-Flora of South Africa) and contributing the information to the World Flora Online initiative following the aggregator portal approach, a method described here that might be useful for other countries with high phytodiversity. [ABSTRACT FROM AUTHOR]

Aim Dioscorea (Dioscoreaceae) is a predominantly pantropical genus (< 600 species) that includes the third most important tropical tuber crop and species of pharmacological value. Fossil records from both the Northern and Southern Hemispheres were used to test hypotheses about the origin of the genus Dioscorea, and to examine potential macroevolutionary processes that led to its current distribution. Location Pantropical distribution. Methods Divergence times were estimated using the most comprehensive phylogeny of the group published to date based on plastid sequences and fossil calibrations, applying a relaxed-clock model approach. Ancestral areas and range shifts were reconstructed using time-stratified likelihood-based models, reflecting past continental connectivity and biogeographical models incorporating the spatial range of fossils. Results Fossil-informed biogeographical analysis supported colonization of the Nearctic by ancient yam lineages from the western Palaearctic and subsequent migration to the South. Most of the pantropical South American, African and Southeast Asian lineages experienced a relatively recent diversification in the Oligocene-Miocene. Long-distance dispersals were inferred for the colonizations of the New World, Africa and Madagascar. Main conclusions Dioscorea likely originated between the Late Cretaceous and the Early Eocene in the Laurasian Palaearctic, followed by possible dispersal to South America via the Eocene North Atlantic Land Bridge. [ABSTRACT FROM AUTHOR]

This paper provides an up-to-date linear sequence of monocot families and genera (excluding Orchidaceae and Poaceae) based on current phylogenetic evidence. The sequence is provided in a numbered list of each of the 1225 genera in 75 monocot families, together with a complementary alphabetical list. The sequence represents a standardized tool for the organisation of monocot herbarium collections. [ABSTRACT FROM AUTHOR]

Herbarium specimens are a vital resource in botanical taxonomy. Many herbaria are undertaking large-scale digitization projects to improve access and to preserve delicate specimens, and in doing so are creating large sets of images. Leaf characters are important for describing taxa and distinguishing between them and they can be measured from herbarium specimens. Here, we demonstrate that herbarium images can be analysed using suitable software and that leaf characters can be extracted automatically. We describe a low-cost digitization process that we use to create a set of 1895 images of Tilia L. specimens, and novel botanical image processing software. The output of the software is a set of leaf characters. As a demonstration of this approach, we extract the length and width of a large number of leaves automatically from images of whole herbarium specimens. We show that the lengths and widths that we extract are very strongly correlated with values in a published account of cultivated species, but are also consistently smaller. We discuss some particular features of herbarium specimens that may affect the results of this form of analysis, and consider further applications to extract characters such as leaf shape and margin characters. [ABSTRACT FROM AUTHOR]

The systematic relationships of Stenomesson Herb. And other Andean genera of Amaryllidaceae are discussed and one of its members, S. Pearcei Baker, is compared to similar species, described and illustrated. The cultivation requirements, habitat, distribution and conservation status of S. Pearcei are discussed. A lectotype is chosen. [ABSTRACT FROM AUTHOR]

Outstanding questions on floral structure in the small family Stemonaceae (Pandanales) include whether the gynoecium is monocarpellary, whether they possess floral nectaries, and how dimery and pentamery evolved in the family. To help resolve these issues we present new data on comparative floral anatomy in three genera of Stemonaceae in the context of a revised phylogenetic analysis using a "total evidence" approach with combined data from three genes (plastid rbcL, atpB and nuclear 18S rDNA) plus morphology. The monocarpellary condition is a synapomorphy for a clade comprising Croomia, Stemona and Stichoneuron, and the unilocular tricarpellary condition is an autapomorphy for Pentastemona. Nectaries are absent, but the densely papillate tepals may function as osmophores, especially in Croomia and Stichnoneuron. The hypothesis that the pentamerous condition in Pentastemona evolved as a result of suppression of an outer tepal and stamen, and thus represents an intermediate stage between trimery and dimery, is not contradicted by its phylogenetic placement as sister to other Stemonaceae, which are dimerous. However, since pentamery also occurs sporadically in the closely related family Triuridaceae, and dimery (and/or tetramery) occur in other Pandanales, this indicates that merism is relatively labile within the order, and that dimery and pentamery have both evolved separately and iteratively from a trimerous condition. [ABSTRACT FROM AUTHOR]

Premise: We developed a target enrichment panel for phylogenomic studies of Dioscorea, an economically important genus with incompletely resolved relationships. Methods: Our bait panel comprises 260 low‐ to single‐copy nuclear genes targeted to work in Dioscorea, assessed here using a preliminary taxon sampling that includes both distantly and closely related taxa, including several yam crops and potential crop wild relatives. We applied coalescent‐based and maximum likelihood phylogenomic inference approaches to the pilot taxon set, incorporating new and published transcriptome data from additional species. Results: The custom panel retrieved ~94% of targets and >80% of full gene length from 88% and 68% of samples, respectively. It has minimal gene overlap with existing panels designed for angiosperm‐wide studies and generally recovers longer and more variable targets. Pilot phylogenomic analyses consistently resolve most deep and recent relationships with strong support across analyses and point to revised relationships between the crop species D. alata and candidate crop wild relatives. Discussion: Our customized panel reliably retrieves targeted loci from Dioscorea, is informative for resolving relationships in denser samplings, and is suitable for refining our understanding of the independent origins of cultivated yam species; the panel likely has broader promise for phylogenomic studies across Dioscoreales. [ABSTRACT FROM AUTHOR]

Societal impact statement Summary Global yam production is centred on West Africa, but there are significant knowledge gaps about farm‐level diversity across much of the region, and especially in Guinea. Although yam production is increasing in Guinea, in the longer term, varietal diversity and the sustainability of agri‐systems are at risk. Documentation of local crop diversity is essential as a baseline to understand trajectories of past and future varietal loss. This study utilises interdisciplinary approaches, which are needed to help understand the ways historic crop diversity is created and maintained within indigenous agricultural and food heritage systems, as well as the reasons for its loss over time. Yams are important staple foods in many tropical and sub‐Saharan countries. The ‘yam belt’ extends from Guinea to western central Africa. However, yam cultivation is comparatively little researched or documented in Guinea, and the country is commonly not included within descriptions of key yam growing areas in Africa. Our study utilises ethnobotanic methods and plant specimen collections to fill these gaps in West African yam research. Interviews with over 70 farmers from six villages across the Kankan region of Guinea provide information on yam cultivation and diversity, and changes in living memory over the past 40 years. We present the analyses of ethnobotanical data from Haute‐Guinée on yam cuisine, and commercialisation, and on changes to the range of varieties grown over time. The annual cycle of indigenous yam agri‐systems remains a key part of rural life, food systems and economy. However, interviews revealed dramatic temporal changes over the last 40 years. Although yam production has increased, a narrow range of commercial cultivars is currently displacing the historically‐rooted local diversity. The expansion of yam cultivation is regarded locally as having relied on a shift to more unsustainable and extensive land use, and with herbicides and chemical fertilisers replacing intensive organic soil management. This has implications for research and development in sub‐Saharan agriculture for yams and other important native West African crops in the future. [ABSTRACT FROM AUTHOR]