Kew ScientistScience news from the Royal Botanic Gardens at Kew and Wakehurst Place

Spring 2015 Issue 47

ISSN: 0967-8018

1www.kew.org Kew Scientist Spring 2015 Issue 47

Digitising Kew’s collectionsDigitisation strategies at Kew

The new science strategy of RBG Kew recognises the need to increase access to its 8.5 million collections and sets an ambitious target of digitising 80% of these by 2020. Kew is seeking to reach this target with two strategies: rapid digitisation of large parts of the collections using modern technologies and smaller-scale projects capturing more in-depth data from specific collections.

Examples of the rapid digitisation approach are the imaging of all Kew’s herbarium specimens of the potato genus (Solanum) and yam family (Dioscoreaceae) in collaboration with the Natural History Museum, (London) and Picturae, a specialist digitisation company based in The Netherlands. In contrast, in-depth data will start to be be captured from Kew’s 150,000 microscope slide collection following the recent acquisition of a digital microscope slide scanner.

Contact: Dr Alan Paton (a.paton@kew.org)

Digitisation of type specimens

This year sees the culmination of a long-term endeavour which counts among its achievements the digitisation of all the type specimens deposited in Kew’s herbarium. Initiated in 2004 as the African Plants Initiative (API), with generous support from the Andrew W. Mellon Foundation, the digitisation work grew rapidly to encompass numerous herbaria, creating high quality (600 dpi) images of African type specimens, and detailed transcription of all associated data to common data standards. The Latin American Plants Initiative (LAPI) built on this success and by 2009 the endeavour had grown into the Global Plants Initiative, eventually involving 329 partner herbaria worldwide and imaging a cumulative total of 2.2 million herbarium sheets including nomenclatural types, other historic and original material, and specimens of plants endemic to a single tropical country. The images and data mobilised are consolidated in a single resource at JSTOR Global Plants: http://plants.jstor.org.

Kew’s contribution to the Global Plants Initiative and its predecessors (API and LAPI) included the provision of imaging equipment, staff training and technical support to herbaria as they joined the network of contributors. The main focus of digitisation efforts at Kew has been

specimens filed in red covers within the main Kew herbarium, which include confirmed types, putative types and other historic material. Over 325,000 such sheets at Kew have been digitised to date, and this work is expected to be completed over the summer of 2015. In addition, the Mellon-funded digitisation team have imaged all of the specimens (> 25,000) in the East India Company Herbarium, which is rich in unmarked types, and conducted pilot projects on imaging important material in the Fungarium (> 4,000 specimens). Kew’s herbarium specimen images are also available at www.kew.org/herbcat.

Contact: Dr Eimear Nic Lughadha (e.niclughadha@kew.org)

Economic Botany CollectionsKew’s Economic Botany Collection has been online since 2012, making available full data for nearly 90,000 ethnobotanical specimens. A major upgrade occurred in 2014 with the addition of 5,500 specimens of materia medica from the Harrod Collection of the former Chelsea College, donated by King’s College London. The online catalogue has both raised the visibility of the Economic Botany Collection and enabled users to target specimens more effectively; data can also now be downloaded for use in spreadsheets. The next challenge is to increase the proportion of photographed specimens. So far about 2,500 specimens have been imaged, mainly those used in recent publications and exhibitions. http://apps.kew.org/ecbot/search

Contact: Dr Mark Nesbitt (m.nesbitt@kew.org)

Imaging of herbarium specimens in The Netherlands Photo: S. Knapp

Type specimen of Carex banksii Boott, collected by Charles Darwin Photo: RBG Kew

Examples of the Harrod Collection recently accessioned into Kew’s Economic Botany Collection with data now digitised. Photo RBG Kew

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DirectionScience Strategy

2015 marks the beginning of a new phase in Kew Science. The launch of the Science Strategy in February has set the organisation on a clearly defined pathway in pursuit of a new scientific vision: to document and understand global plant and fungal diversity and its uses, bringing authoritative expertise to bear on the critical challenges facing humanity today. It reinforces Kew’s position as a global resource in plant and fungal knowledge and recognises the value and potential of the collections to contribute to hard-hitting, relevant research. Developed by scientists across Kew, the strategy provides focus and clarity on Kew’s scientific priorities, which are defined as follows:

1. To document and conduct research into global plant and fungal diversity and its uses for humanity.

2. To curate and provide data-rich evidence from Kew’s unrivalled collections as a global asset for scientific research.

3. To disseminate our scientific knowledge of plants and fungi, maximising its impact in science, education, conservation policy and management.

These priorities will enable us to curate, use, enhance, explore and share Kew’s global resource, providing robust data and a strong evidence base for our UK and global stakeholders.

We have also developed an ambitious set of strategic outputs to be delivered by 2020. These include an online portal giving access to information on all the world’s known plant species, an annual report on the State of the World’s Plants, and a target of banking 25% of the world’s seeds by 2020.

Each of our outputs draws on strengths from across the Science Directorate at Kew and will be implemented by the six newly formed research departments: Collections, Identification and Naming, Comparative Plant and Fungal Biology, Conservation Science, Natural Capital and Plant Health, and Biodiversity Informatics and Spatial Analysis. The departments bring out the best in our collections, our people and our partnerships, and with a new vision and strategy we aim to make Kew’s scientific resources a global asset, bringing benefits to science, conservation policy and education worldwide.

The strategy does not claim to have all the answers. The challenges facing humanity will evolve, and science will continue its forward progress. However, understanding and conserving plant and fungal diversity has never been more relevant, and I am excited by the opportunities for Kew’s scientists to continue to produce world-class research and make an important and unique contribution to addressing some of the major challenges of our time.

Prof. Katherine Willis, Director of Science

AwardsIn February 2015, Honorary Research Fellow Peter Brandham was awarded the Peter Barr Memorial Cup by the Royal Horticultural Society at a ceremony in the RHS Lindley Hall in recognition of his work on the chromosomal evolution of Narcissus in cultivation. Herbarium volunteer Sheila Thompson was the 2014 winner in the Long Service category of the London Volunteers in Museums Awards. The Herbarium reorganisation volunteers were the overall winners of the 2014 Marsh Trust Volunteer Awards.In November 2014, Kew magazine won the Environmental Award at the 2014 Garden Media Guild Awards at The Savoy in London. The award was for a piece by Stephanie Pain called ‘Saving for the Future’ on the UK National Tree Seed Project.An Atlas of the World’s Conifers by Aljos Farjon was awarded an Outstanding Academic Title by CHOICE (Current Reviews for Academic Libraries) in January 2015.An exhibit by Joanne Everson, Ilia Leitch and Laurence Hill showcasing the variation in genome size in Fritillaria, using photographic, scientific and horticultural displays, won a Gold Award at the Early Spring Show of the Alpine Garden Society in Harlow, February 2015.

PhDs

The following students, co-supervised by Kew staff, have successfully defended their theses:Paulina Hechenleitner, ‘Biogeography and systematics of South American Vicia (Leguminosae)’ (December 2014). Jacqueline St Quinton, ‘An evaluation of fungal pathogens as biological control agents against the weed Rubus niveus’ (February 2015).

Preferences of horse chestnut leaf miner

A study has examined oviposition preference and larval performance of the horse chestnut leaf miner (Cameraria ohridella) on its native host, Aesculus hippocastanum, and other species of Aesculus that are novel hosts. Cameraria ohridella laid eggs on all species of Aesculus, but showed preferences for A. hippocastanum and the closely related A. turbinata. Successful mine development, however, was observed only on A. hippocastanum and A. turbinata, and these species showed similar leaf traits, which might explain why larvae performed equally well. In contrast, resistant species showed considerable variation in leaf traits, suggesting that different species of Aesculus have different mechanisms of resistance. Entomol. Exp. Appl. 152, 157 (2014).

Contact: Prof. Monique Simmonds (m.simmonds@kew.org)

Soejatmi plants SoejatmiaIn October 2014, Honorary Research Fellow Soejatmi Dransfield ceremonially planted her eponymous bamboo, Soejatmia ridleyi, in Singapore Botanic Gardens. The monotypic genus Soejatmia was described by K.M. Wong in 1993 to accommodate Bambusa ridleyi, misplaced in Bambusa. The new genus was named after Soejatmi for her contribution to the systematic knowledge of Malesian bamboos.

Contact: Dr Soejatmi Dransfield (s.dransifeld@kew.org)

Peter Brandham awarded the Peter Barr Memorial Cup Photo: R. Scamp

Horse chestnut leaves damaged by the leaf miner Cameraria ohridella Photo: T. Kokubun

Soejatmi Dransfield planting Soejatmia ridleyi at Singapore Botanic Gardens Photo: J. Dransfield

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Climbing palm diversityClimbing plants contribute significantly to species diversity and ecosystem processes in tropical rainforests. In palms, climbing species account for 22% of global palm species richness, but their distribution is highly skewed across the tropics. A multi-institution team has analysed the broad-scale patterns and drivers of climbing palm species richness. The study identified multiple origins of the climbing habit between the early Eocene and the Miocene, with diversification rate increases occurring in those lineages leading to the most species-rich groups. Past and present day climatic factors and canopy height partly explain climbing palm species richness, but a strong role for historical contingencies is also evident. Thus, climbing palm origins and diversification are likely to have been driven by a combination of factors including climate, morpho-anatomical innovations, biogeographic history of Southeast Asia, and ecological opportunity due to the evolution of tall dipterocarps in Asian rainforests since the Miocene. Front. Genet. 5, 452 (2015).

Contact: Dr Bill Baker (w.baker@kew.org)

Climate-driven extinctionsSpecies extinction is one of the fundamental processes shaping biodiversity as well as the appearance and function of ecosystems. Extinction of entire groups of related organisms is more likely to have drastic ecosystem consequences than species losses that are spread evenly across the tree of life and is less easily amended by the evolution of new species. Understanding what circumstances lead to the loss of entire branches from the tree of life is crucial.

In the temperate forests of the Northern Hemisphere, many tree genera went regionally extinct due to a global cooling trend that started approximately 50 million years ago. By combining data on fossil and present distributions, environmental

Adaptive species divergence

Research on the plants of Lord Howe Island has revealed some of the most compelling examples of how natural selection can drive the evolution of new species in a very small area. Now, a research team from Kew and Imperial College London has used innovative genetic methods to understand whether individuals of 18 endemic plants on Lord Howe Island are adapted to their local habitat. Unexpectedly, all species studied show genetic evidence of adaptation to the local environment and a third of the species are adapted to their local plant communities. These results further strengthen the case for adaptive species divergence in nature and demonstrate that local adaptation is widespread in plants. Phil. Trans. R. Soc. B 369, 20130342 (2014).

Contact: Dr Alex Papadopulos (a.papadopulos@kew.org)

Genomes ‘frozen in time’?

The royal ferns (Osmundaceae) have traditionally been regarded as ‘living fossils’ due to similarity in morphological appearance between extant species and fossils over 200 million years old. Further evidence for this stasis was recently suggested by scientists from Sweden who discovered a new Jurassic fossil with exceptionally well preserved cellular structures. Indeed, the similarity in size of the fossil cell nuclei with extant species of Osmundastrum led the authors to suggest that genome size had remained unchanged over 180 million years.

Does this mean that the DNA which makes up the genomes of royal ferns has also undergone limited evolution and hence become ‘frozen in time’? To address this, colleagues at Kew, the Natural History Museum (London) and Fairylake Botanical Garden (China) combined new genomic data with those in the literature. The observations indicate that while the genomes of royal ferns are indeed less dynamic and evolving more slowly than other fern lineages, they are not completely ‘frozen in time’ as there is evidence of some limited evolutionary capacity. New Phytol. 207, 10 (2015).

Contact: Dr IIia Leitch (i.leitch@kew.org)

tolerances, and phylogenetic relationships of temperate trees, researchers from Kew and Aarhus University have shown that this cold-driven extinction was concentrated in groups of closely related genera. Therefore, certain parts of the tree of life are overrepresented in the surviving floras, while others are lacking. This effect was most pronounced in the regions that were hardest hit by cold-driven extinction.

Given that many taxa are currently threatened with extinction due to anthropogenic climate change, the study raises concerns that future climate-driven extinctions will prune the tree of life in a similarly non-random way. Ecol. Lett. 18, 263 (2015).

Contact: Dr Wolf Eiserhardt (w.eiserhardt@kew.org)

Plectocomia elongata, a climbing palm Photo: W. Baker

Osmunda regalis – frozen in time? Photo: G. Kite Zygogynum howeanum Photo: W. Baker

Many extinctions occurred in the magnoliid clade (Liriodendron pictured) following the global cooling that started approximately 50 million years ago Photo: W. Eiserhardt.

Drivers of global plant diversity

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Eugenia systematics Eugenia is one of the most species diverse genera in the Neotropics and one of the most taxonomically challenging. In the first phylogenetic hypothesis of Eugenia, based on DNA sequencing and analyses carried out at Kew, researchers from Brazil and Kew have investigated the validity of currently recognised infrageneric groups in Eugenia as well as identifying supporting morphological characters. The study used the largest Eugenia sample analysed to date and included representative species from Africa, Asia and the Pacific. The results confirm that Neotropical genera Calycorectes, Hexachlamys, Phyllocalyx and Stenocalyx should be included within Eugenia to preserve its monophyly. In Eugenia s.l., nine morphologically diagnosable clades are identified. The results provide a basis for a much needed new subgeneric classification for Eugenia. These subgeneric groupings now form the bases for multiple doctoral studies currently underway. Kew Bull. 69, 9497 (2014).

Contact: Dr Eve Lucas (e.lucas@kew.org)

The advent of high throughput DNA sequencing has had a major impact on many areas of biological research, including systematics where the use of genomic data for phylogeny reconstruction has been greatly accelerated. However, the utility of preserved natural history collections for generating genomic datasets is not well known. A new study, led by Kew scientists Bryn Dentinger and Ester Gaya, applied high throughput sequencing to generate 14 whole genome sequences from fungarium specimens and newly collected fungi. Their study, which compiled a dataset

When using next-generation sequencing, most genomic information, especially repetitive elements, is usually discarded without any investigation of content and usefulness. Various types of repeats are scattered across chromosomes in angiosperms and can comprise most genomic DNA. In a new study, the usefulness of these repetitive elements is evaluated in a phylogenetic context by comparative graph-based clustering of next-generation sequence reads. This analysis results in abundance estimates of different classes of genomic repeats that must be treated as continuously varying characters

Researchers from Universidade Federal de Goiás and Kew have produced a DNA-based phylogenetic overview of relationships in a section of Myrcia (sect. Aulomyrcia c.130 species; Myrtaceae) that brings clarity to the systematics of a very complex and ecologically significant group. The researchers also used likelihood to estimate region-dependent rates of speciation, extinction and dispersal, comparing historical climatically stable (refuges) and unstable areas. Phylo-systematic results re-iterate the polyphyly of Myrcia and Marlierea and divide the ‘Aulomyrcia’ clade into morphologically explicable

Phylogenetic signal in repetitive elements

Relationships in Myrcia sect. Aulomyrcia

of >60,000 amino acids from over 200 genes for 35 taxa representing most of the known families of mushrooms in the order Agaricales, demonstrates the feasibility of using traditional fungarium collections for generating genomic datasets, and provides the first reliable subordinal classification for the group. In addition to seven new suborders, this study also provides a set of top performing genes for phylogenomic studies of other fungi. Biol. J. Linn. Soc, in press, doi: 10.1111/bij.12553 (2015).

Contact: Dr Bryn Dentinger (b.dentinger@kew.org)

(programs that do this are available). In six distantly related cases, five flowering plants and one insect (the fruit fly, Drosophila), this method provides generally well-supported relationships that are in accord with results based on standard markers. This methodology is potentially useful in groups where there is minimal variability found in standard phylogenetic markers and hybridisation is suspected. It also provides a wealth of data for comparative studies of genome evolution. Syst. Biol., in press, doi: 10.1093/sysbio/syu080 (2015).

Contact: Prof. Mark Chase (m.chase@kew.org)

groups for imminent monography. The major ecological results are that there is support for a link between Amazonian and northeastern species as well as between northeastern and southeastern species. Lower extinction rates within glacial refugia suggest that these areas were important in the maintenance of current diversity in the Atlantic forest biodiversity hotspots and that range expansion from unstable areas contributed to the highest levels of plant diversity within these refugia. Ann. Bot. 181, 115, 747(2015).

Contact: Dr Eve Lucas (e.lucas@kew.org)

Diversity of mushrooms from a cloud forest in Ecuador Photo: B. Dentinger

Eugenia azurensis Photo: O.Berg

Nicotiana cavicola, one of the species studied that revealed phylogeneatic signal in repetitive elements Photo S. Hopper

Floral and fruit diversity of Myrcia sect. AulomyrciaPhoto: V. Staggemeier

What plants and fungi occur on Earth?

Genome mining from fungarium specimens

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Filling gaps in legume phylogeny A recent study (Mol. Phylogenet. Evol. 84, 112; 2015) has focused on filling the gaps in early diverging lineages of papilionoid legumes. It revealed that the Amazonian monospecific genus Petaladenium is sister to the genus Dussia in the Amburaneae clade, one of the first-diverging lineages of the Papilionoideae. The fimbriate-urceolate-glandular wing petals make Petaladenium unique among legumes. Similar structures on the bracts of some Dussia species and a similar floral morphology support the sister relationship of the two genera. Previously, Petaladenium was considered related to genistoid legumes, but a supplementary study (Phytochemistry 116, 198; 2015) showed that the leaves lacked quinolizidine alkaloids, characteristic of genistoids, and instead accumulated novel pipecolic acids derivatives, a character unique among members of the Amburaneae clade.

Two further studies into the Amburaneae clade have focussed on Amburana, describing the taxonomy of the genus and one new species (Phytotaxa 212, 249; 2015) and floral morphology and development (Int. J. Pl. Sci. 176, 94; 2015). The corolla of Amburana cearensis is reduced to a single petal and the analysis of its floral ontogeny unearthed rare and novel ontogenetic characters that deviate from patterns found in more derived papilionoid legumes. This fits into the emerging picture of an ‘experimental phase’ in the floral evolution of early diverging legumes.

Contact: Dr Gerhard Prenner (g.prenner@kew.org)

Ochnaceae phylogeneticsWith nearly-complete generic sampling for the first time, phylogenetics of family Ochnaceae has been studied using five DNA regions. Based on this, a new classification of Ochnaceae has been published, with Medusagynoideae and Quiinoideae included as subfamilies, and former subfamilies Ochnoideae and Sauvagesioideae recognized as tribes. Medusagynoideae (Medusagyne oppositifolia alone) are weakly supported as sister to Quiinoideae. Ochneae are supported as monophyletic, but Sauvagesieae in the traditional sense are polyphyletic, necessitating recognition of Luxemburgieae

Molecular studies have covered nearly all groups of Orchidaceae, and this wealth of information has revealed many unexpected sets of relationships and required fairly extensive revision of generic limits within many groups. A team led by Mark Chase has reviewed phylogenetic papers published since the reclassification of Orchidaceae in 2003 and proposed an updated classification. Relative to the 2003 classification, the updated classification recognises three new tribes, all in subfamily Epidendroideae, the largest of the five subfamilies recognised. Compared to other large families, such as Asteraceae, the number of genera recognised in Orchidaceae is modest (approximately 740), and several recent cases of major lumping of genera has occurred, propelling many orchid genera into the top ten largest genera, for example: Bulbophyllum, Dendrobium, Epidendrum and Maxillaria. Publication of this revised classification can be used to organise other sorts of studies because it provides a reliable way of knowing the closest relatives of any target orchid genus. Bot. J. Linn. Soc. 177, 151-174 (2015).

Contact: Prof. Mark Chase (m.chase@kew.org)

In terms of pollination strategies, vegetative adaptations and sheer number of species, Epidendroideae, the largest subfamily of Orchidaceae, represent one of the largest angiosperm radiations. A new study has used seven DNA regions to evaluate associations of key characters with diversification. The matrix included representatives of 312 genera (of the roughly 740 recognised in the most recent classification). Likelihood and parsimony analyses yielded highly resolved trees that are in good agreement and show significant support for many key clades. Statistical character-associated diversification analyses were performed and showed that epiphytism is most strongly associated with diversification, followed by dispersal to the New World and anther characters involved with pollinator specificity. However, all other characters examined also exhibited significant association with species richness, indicating that there was no single key character that initiated an episode of explosive speciation. A series of important features evolved at different times, sometimes in parallel, and these often supported diversification. Ann. Bot., in press, doi:10.1093/aob/mcu253 (2015).

Contact: Prof. Mark Chase (m.chase@kew.org)

Bolivian biodiversityKew scientists contributed accounts of Acanthaceae, Convolvulaceae, Cyperaceae, Lamiaceae, Leguminosae and Poaceae to the Catalogue of the Vascular Plants of Bolivia (Monogr. Syst. Bot. Mo. Bot. Gard. 127; 2014). In Kew’s Science Strategy, Bolivia is identified as a focus for developing partnerships to conduct targeted field research and identify priority areas for plant and habitat conservation under Kew`s TIPAs (Tropical Important Plant Areas) programme.

Contact: Dr Bente Klitgaard (b.klitgaard@kew.org)

Updated classification of Orchidaceae

Epidendroideae phylogeny

and Testuleeae. The position of Lophira has varied between earlier classifications, but in the new study it is sister to the rest of Ochneae; endosperm-free seeds and ovules with partly to completely united integuments are thus characters that unite that tribe. Ancestral state reconstructions revealed zygomorphic flowers with adaptations to buzz-pollination, syncarpous gynoecia, numerous ovules, septicidal capsules and winged seeds with endosperm as ancestral states in Ochnoideae. Winged seeds in Medusagyne are not homologous with those in Ochnoideae. Mol. Phylogenet. Evol. 78, 199 (2015).

Contact: Dr Mike Fay (m.fay@kew.org)

Eugenia azurensis Photo: O.Berg

Dehisced fruits of Medusagyne oppositifolia Photo: M. Christenhusz

Seasonally dry woodland of the inter-Andean valleys of Bolivia Photo: B. Klitgaard

What plants and fungi occur on Earth?

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Mapping and monitoring mycorrhizal fungiMycorrhizal fungi are a major functional guild controlling plant-soil interactions. Mapping and monitoring of forest ectomycorrhizal fungi has untapped potential to inform forest management and fungal conservation. However, studies need to reach beyond national boundaries to reflect fungal geographic distributions and their drivers of change. The vast European forest monitoring network, ICP Forests, is an ideal platform for mycorrhizal studies. A study, based on the findings of an NERC-supported workshop organized at Kew in April 2014, has assessed the potential of intensively monitored long-term forest plots in developing and scaling up forest mycorrhizal research and fungal biomonitoring. The authors propose research hypotheses and encourage further discussion by raising questions covering current knowledge gaps. They also make recommendations for scaling up mycorrhizal assessments so as to inform a variety of stakeholders, with a focus on conservation and policy. Discussions will continue at a workshop supported by the British Ecological Society in October 2015 at Kew. Ann. For. Sci., in press, doi: 10.1007/s13595-014-0447-4 (2015).

Contact: Dr Laura Martinez-Suz (l.martinez-suz@kew.org)

Phylogeny, extinction and conservationThe IUCN Sampled Red List Index (SRLI) is a policy response by biodiversity scientists to the need to estimate trends in extinction risk. Kew scientists are actively involved in the SRLI for Plants, Phase I of which provided baseline data predominantly by making assessments using herbarium specimen data. This is due to the overwhelming absence of accurate population data or detailed distribution maps for the vast majority of plant species. This method creates difficulties in re-assessing these species to measure genuine changes in conservation status. However, the same specimen data identify precise localities where threatened species have previously been collected and can be used to model species ranges and to target fieldwork. Thus, Phase II of the SRLI for Plants aims to mobilise an extensive global network of botanists, academics and conservationists to establish an international monitoring scheme. The strategy for prioritising fieldwork efforts to produce a more robust estimation of the SRLI in Phase II has been published in a discussion meeting issue of the Philosophical Transactions of the Royal Society B entitled ‘Phylogeny, extinction and conservation’ (http://rstb.royalsocietypublishing.org/content/370/1662/).

The goal of this discussion meeting issue, outlined in the introductory paper by the organisers (including Felix Forest

Following the rediscovery of Anogramma ascensionis (Ascension Island parsley fern) in 2009, successful propagation work has been carried out by Kew and the Ascension Island Government Conservation Department. In November 2014, ten plants at different developmental stages were planted into the habitat of this critically endangered species on Ascension Island. The success has been outstanding with gametophytes producing over 175 sporophytes, many of which have produced spores, ensuring the full cycle of generations.

Contact: Marcella Corcoran (m.corcoran@kew.org)

Invasive plants are estimated to cost the UK over £1.7 billion each year. Much research has been targeted at trying to understand and predict why some plants become invasive and others do not by comparing traits of invasive and non-invasive species. However, the role of genome size (the total amount of DNA in the nucleus), which varies c. 2,400-fold, has not been widely investigated even though species with large genomes are known to be constrained in many functional traits that have been linked to invasive potential (e.g. minimum generation time, seed characteristics, relative growth rate of seedlings, water use and photosynthetic efficiency). A recent review highlights the many ways that genome size could influence the invasive potential of a species, and argues that such data are needed in comparative macroecological studies on species invasiveness. The authors of the review predict that such data will provide a more complete understanding of how interactions between multiple traits influence the invasive potential of a species. New Phytol. 205, 994 (2015).

Contact: Dr Ilia Leitch (i.leitch@kew.org)

Winners and losers among British and Irish orchids.

Based on the Local Change Survey (published by the Botanical Society of the British Isles) and recent Red List assessments, the current state and the likely future of populations of all native British and Irish orchids have been analysed. This identified likely winners and losers

in the face of climate change and other factors. Winners include Himantoglossum hircinum, Ophrys apifera and Orchis purpurea, while losers include Cephalanthera longifolia, Epipactis palustris, Hammarbya paludosa and Neottia nidus-avis. Changes in woodland management and drying out of localities (due to natural causes or human intervention) appear to be major reasons for the declining populations of some of the losers. Curtis’s Bot. Mag. 32, 3 (2015).

Contact: Dr Mike Fay (m.fay@kew.org)

Currently, there is only one non-lichen fungus species worldwide on the IUCN’s Red List. To begin to address this dearth of information on what fungal diversity is under threat, mycologists from Europe, including Kew’s Martyn Ainsworth, attended a workshop in Sweden aimed at getting the conservation status of more threatened fungal species assessed.

Anogramma success Does genome size influence invasive potential?

and Mark Chase from Kew), was to offer a platform to present the available methods allowing the integration of phylogenetic and extinction risk data in conservation planning. Evolutionary studies have played a fundamental role in our understanding of life, but they have had only a modest involvement in addressing conservation issues. In a third paper in the issue co-authored by Kew scientists, it is shown how incorporating evolutionary history directly in conservation actions is beneficial, particularly given the likelihood that extinction is not random and that phylogenetic diversity is lost at higher rates than species diversity. The authors use evolutionary data on the legumes of Madagascar to show that this evidence is even more compelling in biodiversity hotspots.

Contact: Dr Félix Forest (f.forest@kew.org)

Immature fruits of Eligmocarpus cynometroides, a ‘Critically Endangered’ Madagascan legume Photo: F. Forest

Sporophytes developing on gametophytes of Anagramma ascensionis.

What plant and fungal diversity is under threat?

Neottia nidus-avisPhoto: M. Christenhusz

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Evolutionary history of Aloe A team of scientists led by Kew and the University of Copenhagen have studied evolution in the succulent genus Aloe, shedding light on the world’s preference for Aloe vera over hundreds of related species of Aloe. The common term ‘aloes’ refers to the large Old World genus Aloe (ca. 500 species) and a further 20 species in five smaller related genera, Aloidendron, Aloiampelos, Aristaloe, Gonialoe and Kumara. In this study, a phylogenetic tree constructed with DNA sequence data from about 40% of the aloes—an unprecedented sampling of the group—was used to estimate the distribution of the predecessors of modern aloes using biogeographical methods. The resulting evolutionary hypothesis identified the origin of the aloes to southern Africa approximately 16 million years ago, and the origin of Aloe vera to the Arabian Peninsula more recently. The succulent leaf tissue of Aloe vera is one of the world’s most popular plant ingredients. Many other species of Aloe are used traditionally, but none has the same commercial status. Using the phylogenetic tree to scrutinise patterns in the properties of leaf succulence and medicinal use revealed that aloes with very succulent leaves are the most likely to be used medicinally. Hence, Aloe vera does not appear to have a unique evolutionary history, and the early introduction of the species to major trade routes likely contributed to its popularity and near-cosmopolitan distribution, and the global market it supports today. BMC Evol. Biol. 15,29 (2015).

Contact: Dr Olwen Grace (o.grace@kew.org)

Phytochemicals as micronutrients in health and disease Worldwide, non-infectious diseases (NIDs) – including cardiovascular disease, cancer and diabetes – kill 38 million people each year, and 47.5 million people have dementia, which is a WHO public health priority. While unhealthy diets increase the risk of dying from a NID, intake of dietary phytochemicals has been associated with health benefits. The role of phytochemicals in maintaining health and preventing disease has recently been reviewed by Kew scientists in a study that focused on recent progress on their mechanistic effects, clinical and epidemiological evidence. Phytochemicals emerging as potentially relevant for health, with particular relevance for NIDs, include catechins, resveratrol, curcumin, anthocyanins and isoflavones. It was concluded that evidence for the role of phytochemicals in health and disease is growing, but knowledge of the species in which they occur and their specific associations with health need to be more firmly understood and established from more robust data using authenticated plant material and phytochemically characterised preparations. Curr. Opin. Clin. Nutr. Metab. Care 17, 558 (2014).

Contact: Dr Melanie Howes (m.howes@kew.org)

Food security from cultivated yams

Across Madagascar, wild endemic yam species are collected from open access areas and used as a food of last resort, at times when other crops fail. An alternative is to cultivate yams. A notable knowledge gap in using yam cultivation to enhance local food security is a paucity of data concerning demand for cultivated yams and whether people in the relevant communities prefer the wild yam species to the exotic cultivated yam species. Understanding these preferences contributes to addressing the issue of poor food security causing extinction pressure on specific native yams and helps to determine whether yam cultivation can reduce this. A study, using a preference choice experiment approach, has found that subsistence farmers would rather obtain the cultivated but introduced species Dioscorea alata as a standby rather than the three wild species of yam that occur locally: D. kimiae, D. arcuatinervis and D. seriflora. The study shows that a choice experiment can provide information about preferences in a subsistence setting and demonstrates how validity tests can be incorporated into a choice experiment approach. Afr. J. Agric. Econ. Rural Develop. 31, 165 (2015).

Contact: Dr Tim Harris (t.harris@kew.org)

Plants contributing to natural capital

Aloe vera, a globally popular succulent plant Photo: O. Grace

Comparative seed biologyHomoglutathione in legumesGlutathione ( -glutamylcysteineglycine), a tripeptide found in all higher eukaryotes, has antioxidant properties and plays a key role in maintaining cellular redox homeostasis. A glutathione homologue, homoglutathione, is found only in some species of Leguminosae and is believed to have arisen as a result of gene duplication after the divergence of the Leguminosae. Previous studies on the distribution of homoglutathione have focused only on species belonging to seven of the 35 tribes of Leguminosae, all of which belonged to subfamily Papilionoideae.

Recent research by Kew scientists into the distribution of glutathione and homoglutatione in legume species, representing 30 tribes across all three sub families, revealed that homoglutathione was restricted to the Old World clade of Papilionoideae. The appearance of homoglutathione coincides with a whole genome duplication event that is proposed to have occurred after divergence of the Old World clade. Not all species in the Old World clade produce homoglutathione, so the ability to synthesise homoglutathione may have been lost in some species. Homoglutathione showed a different tissue-specific distribution to glutathione, which suggests that it may play a distinct role in some tissues. Phytochemistry 115, 175 (2015).

Contact: Dr Louise Colville (l.colville@kew.org)

Seed persistence

A team of scientists from Australia and the UK have reviewed the ecophysiology of seed persistence. Seed persistence is a strategy enabling plants to disperse seeds through time and avoid germination in adverse seasons. It also enables seeds to be stored for long periods ex situ. Seeds dispersed into the natural environment encounter dynamic climatic, soil and site conditions, which result in variable persistence times. Thus, persistence of individual seeds is an expression of numerous seed characteristics including inherent dormancy, longevity and defence, and how these characteristics are influenced by the immediate environment of the seed. An understanding of seed persistence is critical for weed management, agricultural management and restoration programmes. The authors of the review propose a resistance-exposure model as a first step in addressing the need to predict how seed, species, climate, soil and site factors influence overall persistence. Biol. Rev. 90, 31 (2015).

Contact: Dr Louise Colville (l.colville@kew.org)

Centrosema pubescens: contains homoglutathione in its roots and seedsPhoto: L. Colville

8

Each year Kew scientists publish numerous species of plants and fungi from around the world that are new to science. Discovering new species in the glasshouses at Kew, rather than in a remote corner of the tropics, is unusual. Nevertheless, two new species (a pitcher plant and an orchid) have recently been discovered in Kew’s living collections.

Curating Biocultural Collections: A Handbook (Eds J. Salick, K. Konchar & M. Nesbitt, Kew Publishing, 2014; ISBN 978 18 2464 98 4) provides advice for successful

management of collections that document the richness and diversity of human engagement with the natural world. The book places a strong emphasis on meeting the needs of collection users and encourages ethical and equitable engagement with source communities, and it gives valuable insight into biocultural collections for anyone working to preserve these valuable resources. The Plants of Sudan and South Sudan: An Annotated Checklist (by I. Darbyshire, M. Kordofani, I. Farag, R. Candiga & H. Pickering; Kew Publishing, 2015; ISBN 978 18 4246 47 3) is the first publication dedicated to the flora of the Republic of Sudan and the recently seceded Republic of South Sudan. It provides a baseline reference for all future botanical and conservation work in the Sudan region.

Treasured Trees (by M. Yamanaka, C. Harrison & M. Rix; Kew Publishing, 2015; ISBN 978 18 42465 86 8) is a celebration of the oldest and finest trees growing at the Kew, with

beautiful botanical art by Japanese artist Masumi Yamanaka.

On the Forests of Tropical Asia: Lest the Memory Fade (by P. Ashton; Kew Publishing/Arnold Arboretum, 2015; ISBN 97 8 1 842464 75 5) is the first book to describe the forests of the entire tropical Asian region, from Sind to New Guinea. It opens with chapters on physical geography and geological history and then moves on to address forest and tree structure and dynamics, floristics, and symbiotic organisms, as well as genetics, evolutionary history, species diversity, and human impact. A final chapter covers future policy and practice options for saving what remains.

Atlas of Wood Diversity in the Cerrado of São Paulo (by J. Sonsin, P. Gasson, S. Machado, C. Caum & C. Marcati; Editora FEPAF, 2014; ISBN 978 85 98187 50 1) describes the wood anatomy and macromorphology of 91 species of trees and shrubs collected in a 180 ha nature reserve in the state of São Paulo.

In partnership with Queen Mary University of London, Kew will launch a new joint MSc course in Plant and Fungal Taxonomy, Diversity and Conservation in September 2015, based at Kew. With only a small percentage of the planet’s diversity formally described by science, it is more important than ever to train a new generation of taxonomists who will go on to describe, understand and conserve biodiversity. The new MSc course delivers vital plant and fungal identification skills in combination with a thorough grounding in molecular systematics, evolutionary biology and conservation policy, theory and practice. The one-year taught Masters programme is designed for biology graduates or graduates of other relevant natural science degree courses. Applicants with relevant professional experience in science will also be considered. Applications should be made through Queen Mary University of London.Kew is also organizing an Applied Plant Taxonomy, Identification and Field Survey Skills Course from 7 to 18 September, 2015. The course is designed for early career environmental scientists and PhD students of any discipline, with competitive bursaries supported through NERC funding. Contact: Dr Gemma Bramley (g.bramley@kew.org)

New pitcher plantThe longstanding Nepenthes research collaboration of Martin Cheek (Kew) and Matthew Jebb (National Botanic Gardens, Ireland) has resulted in many new species of Nepenthes being described. Twelve new species from the Philippines alone were published in 2013, resulting from examination of herbarium specimens loaned to Kew from diverse botanical institutes. In addition to these, the sterile specimen ‘Elmer 14248’ collected in 1912 from Mt Masaya in Mindanao did not fit any known species. While verifying identifications of the living collections in Kew’s glasshouses, Martin Cheek noticed a plant mislabelled as N. copelandii that connected it to the Elmer specimen. Eventually the living plant flowered, and the herbarium specimen made from it was a close match for the Elmer specimen. Records showed that the Kew plant had been collected from Mindanao in 1997 from a location close the Elmer specimen. The species has been named Nepenthes zygon, and it is only known from a small number of individuals at two locations in Mindanao, one of which is reported to have been cleared for timber, so the species has been assessed as Critically Endangered. Blumea 59, 144 (2014).

Contact: Dr Martin Cheek (m.cheek@kew.org)

New orchid in quarantineDuring a fieldtrip to the Cardamom Mountains in Cambodia in November-December 2013, André Schuiteman and Christopher Ryan had permission to collect a number of living orchid specimens for Kew. Among these was a small epiphytic orchid, which superficially resembled the widespread Porpax elwesii. About a dozen specimens were seen, all growing on the trunk of a fallen tree. The flowering season of this species being almost over, only two flowers were left, which were collected and preserved in spirit. A few living plants were brought back to Kew, where they flowered a year later in the Quarantine House. A closer examination of the bell-shaped flowers revealed that it was not P. elwesii, but an undescribed species. It differs from P. elwesii especially in the much broader petals that are covered with large, translucent warts. The new orchid will soon be published and named in Kew Bulletin.

Contact: André Schuiteman (a.schuiteman@kew.org)

Nepenthes zygon Photo: M. Cheek

The undescribed species of PorpaxPhoto: A. Schuiteman

New species found in Kew glasshouses

New books MSc in Plant and Fungal Taxonomy, Diversity and Conservation

Kew Scientist, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB. Tel: +44 (0)20 8332 5000 Fax: +44 (0)20 8332 5310 Web: www.kew.orgPublished in Spring and Autumn.

Editor: Dr M. FayProduction Editor: Dr G. KiteDesign: Design team, RBG Kew

Editorial advisory team:F. Cook, Dr C. Clubbe, Dr F. Forest, Dr E. Gaya, Dr G. Lewis, Prof. M. Simmonds

RBG Kew receives about half its funding from the UK Government through the Department for the Environment, Food and Rural Affairs (Defra).

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