Large-Scale Syntheses
Recent Achievements
Collections (2001-2005)
199,353 specimens have been accessioned into the Herbarium. The herbarium catalogue, HerbCat, was developed in 2002, and since then, 179,776 herbarium specimens have been databased and added.
Over 60,000 type specimens from Africa databased and imaged within the African Plants Initiative. 21,000 Monocot types have been databased and imaged.
13,000 seed collections of 8,000 wild plant species added to the Millennium Seed Bank, mainly from partner countries in the drylands; of which more than 25% of species are endangered, endemic or of economic value.
A large-scale synthesis of taxon-based seed biological information has been created and made available over the web as the Seed Information Database, incorporating information on c. 22,000 species by the end of 2005.
The RBG Kew DNA Bank now numbers nearly 24,000 accessions of which 10,000 have been added since 2001, representing 9,100 species. Over 700 new DNA samples were added to the bank via a Darwin Initiative project on DNA banking of the Flora of South Africa and 300 DNA samples of species used in traditional Chinese medicine were banked.
Baseline Plant Diversity Research (2001-2005)
International attention and resources have been focused on GSPC Target 1 (a widely accessible working list of known plant species) through publications, international meetings e.g. gap analysis meeting and seminar at International Botanical Conference (Vienna) and fundraising (Moore Foundation, GBIF, BBSRC).
Checklists for 106 families, around one third of known flowering plants, have been made accessible via Kew’s website.
In collaboration with New York and Missouri Botanical Gardens we have developed tools and procedures to accelerate checklist production as part of the iPlants project.
Over 50,000 fern names were added from the Index Filicum to International Plant Names Index (IPNI) making the data available on the internet for the first time. IPNI has been searched on average around 10,000 times per day.
Both the Kew Record of Taxonomic Literature and the Plant Micromorphology Bibliographic Database were launched on the RBG Kew external website in 2001. In 2002 they were included as datasets in Kew’s ePIC (electronic Plant Information Centre) and have been queried over 600,000 times each since their launch.
Comparative Plant Biology (2001-2005)
Large-scale phylogenetic trees have been published where molecular clock methods have been applied. A dated supertree has shown a complex pattern of diversification across all angiosperm families. In vascular plants as a whole, dating phylogenies using molecular clocks proved more difficult, for example with tree ferns being 'molecular living fossils' and their low rate of molecular change being consistent with their morphological stasis in the last c. 170 million years.
Our research has shown that species richness of some taxa in the Cape of S Africa is of recent origin and associated with the effects of a recent period of dryness (Richardson et al., 2001), whereas other radiations are much older (Goldblatt et al., 2002).
Research demonstrated that pollinator specialization in the fig-wasp symbiosis led to the parallel diversification of both partners, thereby providing an unparalleled example of plant-insect co-divergence over geological times, and for at least the past 60 million years (Ronsted et al., 2005).
Research showed that species response to changes in climate can be based on selection of genotypes within populations differing in their response to temperature in the year of germination (Kelly et al., 2003).
The APG classification of the orders and families of angiosperms was updated in 2003 and demonstrated that there can be stability in a classification based on cladistic analyses of molecular data (APG II, 2003).
Research showed that a population-based marker (AFLP) can reproduce phylogentic patterns obtained with DNA sequences as well as providing detailed information about relationships of populations (Hodkinson et al., 2002; Richardson et al., 2003).
Implications of the APG system of angiosperm classification for testing hypotheses concerning evolutionary aspects of the angiosperms (genome sizes, morphological evolution, floral development etc) published (Soltis et al., 2005).
A special issue of the American Journal of Botany was published, dedicated to unravelling the plant and fungal trees of life and edited by Palmer, Soltis and Chase (2004).
Sampling for the angiosperm tree was broadened, moving from the familial to generic level, thereby allowing a more accurate inference of the general patterns and processes of angiosperm evolution; using accurate ages and geographic distribution in combination with other attributes (species number, environmental energy loads, key innovations etc.). So far a tree with c. 2,500 genera has been produced based on rbcL data, and simulation studies have shown that a well resolved complete-generic tree could be achieved using only a few plastid genes, such as rbcL. DNA banks of wild plant material are crucial to achieving this goal, and a plea for DNA banking has been published in a letter in Science and via a manual DNA and Tiisue Banking for Biodiversity and Conservation co-published by Kew and IUCN in January 2006.
Internal support (bootstrap percentages) was shown to be effectively assessed for large phylogenetic matrices of DNA sequences (more than 300 terminals) with rapid methods (Salamin et al., 2003).
Telomeres of many angiosperms were shown to exhibit a great deal more diversity than previously thought. Continued probing into the evolution of telomere sequence organization in plants revealed that the majority of species in the Asparagales clade which lack the ‘typical’ Arabidopsis-type sequence have replaced it with the human-type telomere repeat sequence (Sykorova et al., 2003a). Further, the first eudicot genera to lack typical Arabdiopsis-type telomere sequences were identified as Vestia and Sessea (Solanaceae) (Sykorova et al., 2003b).
The elucidation of factors that contribute to cell viability loss is compromised by the lack of a universal measure that quantifies ‘stress’. We showed in four species subject to ageing or desiccation that seed viability changes with an alteration in the half-cell reduction potential of glutathione, a major cellular antioxidant and redox buffer. This pattern was confirmed during a meta-analysis of cell viability data representative of 13 plant and fungal orders. This universal stress marker for cell viability provides a metabolic interface between stress and orchestrated responses, including programmed cell death (PCD). An end point of PCD is DNA degradation and this has been established in ageing dry seeds, as has the temporal loss of telomeres. This study is published in a high impact factor journal (CIF 5).
Development of a strategy for the DNA barcoding of land plants was outlined in a special issue of the Philosophical Transactions of the Royal Society edited and co-authored in part by Kew staff.
A number of targeted genera have been used to produce complete species-level analyses and encompass both putative factors of speciation and provide replicates of the observed patterns, thereby permitting greater generalisation (e.g. publications of pollinator-driven radiations in coastal rainforests in Brazil, and energy theories for the southern African Flora).
Several large external grants have been secured (e.g. Darwin Initiative, Leverhulme Trust, European Commission) to combine phylogenetic trees, DNA barcoding and other taxonomic data to answer evolutionary/ecological questions and provide outcomes for conservation (e.g. maps of phylogenetic diversity for the Cape Flora, DNA-barcoding and ecological monitoring of Mesoamerican orchids, and diversification of Proteaceae in Mediterranean hotspots).
There has been a movement towards more detailed (and mechanistic) explanations of evolution in several case studies, making use of RBG Kew’s current expertise in combination with evolutionary developmental genetics, evolutionary ecology, population biology and other innovative approaches (e.g. speciation genomics in Lord Howe Islands palms, and eco-evo-devo in the African beetle daisy).
The evolutionary and ecological drivers for seed desiccation (in)tolerance were investigated in a broad range of taxa. Cross-species and/or phylogenetic analyses were used to compare seed traits of 225 species (from > 35 families) from semi-deciduous forest in Panama and 69 species from dryland Africa and a predictive tool for seed desiccation sensitivity developed based on 104 species and two traits, including seed mass. The probabilistic model was validated on European species and work published in three higher impact factor journals, including Kew’s first ‘open access’ article published in Annals of Botany.
A large-scale synthesis of taxon-based seed biological information has been created and made available over the web as the Seed Information Database, incorporating information on c. 22,000 species (GSPC Target 3).
Since 2001 two further compilations of DNA amounts for over 900 species have been published in hard copy form, bringing the total number of lists published to eight.
Increasingly robust phylogenetic trees and an increase in the amount of plant genome size data have enabled the nearly 2,000-fold range of genome sizes to be viewed from a phylogenetic context. Superimposing genome size data onto a tree for land plants has highlighted similarities and differences in genome size profiles among different plant groups and provided the first insights into the ancestral genome size of land plants (embryophytes; Leitch et al., 2005).
Large scale analysis of genome size data from the Plant DNA C-values database revealed that genome downsizing (i.e. loss of DNA) following polyploidy is a widespread phenomenon of considerable biological importance (Leitch and Bennett, 2004).
The application of multicolour fluorescent chromosome painting approaches has contributed to new insights into the structure, organization and evolution of Brassicaceae genomes. These approaches have revealed details about the polyploid nature of species traditionally considered to be classical diploids and advanced our understanding of karyotype evolution. The results have been published in higher impact journals (Lysak et al., 2005).
The separation of dormant, non-germinating seeds from inviable non-germinating seed has a crucial impact on the interpretation of germination tests. In wild species the timing of such an assessment can be delayed by weeks or months from the start of the test. This delay was dramatically reduced to hours or days for c. 200 species by using the vital stain, tetrazolium. Comparative analyses revealed an interfering effect of seed oils in the assessment, particularly in Asteraceae, Brassicaceae, Solonaceae and Pinaceae.
A large genus-level supertree of grasses has been published and is being used to look for grass-herbivore co-evolution and the origin of savannas and C4 photosynthesis.
Thirty six papers on pollen structure and evolution have been authored by Kew staff in peer-reviewed publications since 2001, including six in higher impact journals. One staff member was awarded a PhD for successful completion of a thesis on pollen structure in caesalpinioid legumes (Banks, 2004). Another PhD on pollen was successfully defended (Schols, 2004).
Thirty five papers on floral evolution have been published in peer-reviewed publications since 2001, including seven in higher impact journals. Two DPhil theses were successfully defended (Moylan, 2001; Wortley, 2004).
An International Symposium on Palynology was hosted by the Linnean Society in 2005, to mark the retirement of Kew Palynologist, Dr Madeline Harley.
A popular book on pollen was published authored by Rob Kesseler and Madeline Harley (2004).
Three papers were published on cell inclusions since 2001.
Over 40 papers on different aspects of wood structure and evolution have been published in peer-reviewed journals since 2001, including 13 in higher impact journals. One PhD thesis was successfully defended (Lens, 2005).
Over 70 papers have been published since 2001 on different aspects of comparative phytochemistry providing data on the distribution of flavonoids, essential oils and alkaloids among different plant families. Ten PhD’s on different aspects of plant chemistry were successfully defended.
The appointment of two lecturers with joint appointments between Kew and Imperial College, University of London has facilitated the development of joint research projects on different aspects of plant ecology and plant-fungal interactions.
The appointment in 2004 of a wood specialist with interests in xylem evolution and function has reinforced existing links with an international research community, and augmented existing studies focusing on systematics, wood identification, and applied projects. Preliminary studies on pit membranes with thickenings known as tori indicate a correlation between presence of tori and narrow tracheary elements with helical thickenings, indicating that torus-bearing pit membranes show a more efficient hydraulic efficiency and increased safety from embolism. These results address questions about the functional and ecological significance of pit membrane structure.
Sustainable Utilisation of Plant Resources (2001-2005)
Three posters were produced which enable front line custom officers to identify the CITES timbers mahogany (Swietenia macrophylla), afromosia (Pericopsis elata) and ramin (Gonystylus spp.).
Insidewood, an interactive wood identification database (produced collaboratively with NCSU, USA) was launched online (http://insidewood.lib.ncsu.edu/search/) in 2004.
Funds from the World Cancer Fund supported research at Kew and Leicester University on the anti-cancer activity of compounds present in wild relatives of food plants lost or decreased in concentration during cultivation. As a result of this research the cancer protective properties of tricin isolated from rice bran was identified.
The Medicinal properties of 80 species of British plants were studied. Data collected on the anti-diabetic (1,700 spp.) and anti-tuberculosis (1,200 spp.) properties of plants, with an emphasis on African and British species of plants.
Studies of the wild harvested vegetables eaten by communities in parts of Kenya and South Africa started with the aim of studying the nutritional and health benefits of these species.
The evolution of plant life forms and their association with habitat was investigated by studying the potentially germination-enhancing effect of plant-derived smoke. Of the 301 horticulturally important fynbos species tested, smoke significantly improved germination in about 50% of these species, particularly in Asteraceae, Ericaceae, Proteaceae and Restionaceae, but not in families of geophytes such as Amaryllidaceae. Serotinous species were less likely to respond to smoke than non-serotinous species, as were resprouters compared to obligate seeders.
Since 2001, over 2,500 different species of plants have been studied for their role in different aspects of plant-animal interactions, making a total of over 11,000 species studied since 1985. In the last five years over 400 compounds isolated from some of these species were tested for antifeedant activity and the results presented in 60 publications.
Reviews were published on the distribution of flavonoids within different plant families.
Over 2,000 samples (incuding over 3,500 photograghs) of plants and plant-derived drugs used in traditional medicine collected from China to enable more species to be authenticated.
Methods have been developed for the chemical authentication of 55 different plant species currently being traded in Britain.
Since 2001, over 10,000 scientific enquiries have been answered about the sustainable and economic uses of plants, many leading to new funded projects.
Conservation and Environmental Monitoring (2001-2005)
Kew played a key role in the negotiation of the Global Strategy for Plant Conservation (GSPC) and its adoption at the sixth meeting of the Conference of the Parties to the Convention on Biological Diversity. Following this, Kew was a lead partner in the development of Plant Diversity Challenge, the UK response to GSPC.
Species-level conservation assessments were prepared and disseminated, representing a significant contribution towards GSPC Target 2.
Contributed to conceptual development and methodology for the Sampled Red List Index and now co-ordinating plant-focused input to this global indicator of biodiversity change.
Advised the UK government on over 25,000 CITES licence applications and supported inspections of 45,000 plants and over 62 tonnes of timber for HM Revenue and Customs.