Download Is climate change differentially affecting C3 and C4

2017_69: Is climate change differentially affecting C3
and C4 plant lineages in Africa? – a case study of
tribe Abildgaardieae
Supervisors: Professor Isabel Larridon ([email protected]), Professor Iain Colin
Prentice (Life Sciences)
Department: Royal Botanical Gardens, Kew
C4 photosynthesis is an evolutionary response to climate change (incl. aridification).
C4 species are few compared with C3 plants, but account for 25% of primary
productivity and dominate (sub)tropical grasslands. Investigating C4 evolution is
important to understand the origin and function of the biosphere and meet growing
demands for resources. Multiple independent origins of C4 in Cyperaceae provide
opportunities to study the response of C3 and C4 lineages to climate change. The
largest diversity of C4 sedge lineages occurs in Africa allowing investigation of C4
evolution within its unique climatic and biogeographical history. Africa is undergoing
aridification at a scale and level only comparable to Australia. Studying adaptation in
African flora may be key to decipher long-term evolutionary response to global
warming.
Evolutionary relationships in Cyperaceae (sedges) have been studied using a
conventional Sanger sequencing approach, however, robust phylogenetic resolution
across the family remains patchy. Relationships between C4 taxa are ill-understood,
hampered by an apparent faster rate of diversification leading to limited topological
resolution and support. Abildgaardieae (>500 spp.), a tribe diverse in Africa (>150
spp.) including e.g. Bulbostylis (C3/C4), Crosslandia (C4), Fimbristylis (C3/C4),
Nelmesia (C4), and Nemum (C4), remains one of the most poorly resolved sedge
groups due to a lack of research focus and complicated taxonomy. Very little is known,
even at generic level. We aim to build a dated phylogeny to resolve relationships in
C4 lineages of tribe Abildgaardieae and identify their closest C3 relatives. An
accurately dated and robust phylogeny is critical to determine evolutionary drivers and
processes, and inform how plants respond to environmental pressures. Molecular data
will be generated using the high-throughput sequencing technique Hyb-Seq which
enables highly cost-efficient genome-wide data capture for phylogenomics. A new
angiosperm-wide Hyb-Seq enrichment probe kit is being developed for the Kew
Science Plant and Fungal Trees of Life (PAFTOL, http://science.kew.org/strategicoutput/plant-and-fungal-trees-life) Strategic Output programme based on
transcriptome and genome data generated by the oneKP project (www.onekp.com).
For more information on how to apply visit us at www.imperial.ac.uk/changingplanet
Science and Solutions for a Changing Planet
A Cyperaceae-specific probe kit, developed by collaborating researcher Dr Tamara
Villaverde at The Morton Arboretum/The Field Museum, is also available for use.
Good-quality DNA of a range of Abildgaardieae species is already available at the Kew
DNA Bank, and aliquots and/or additional samples are available from partners at
Ghent University (Belgium), Canada, Hungary, South Africa, and the USA.
Biogeographical and ecological niche modelling informed by Kew herbarium records
will be employed to infer whether evolution of C4 precedes radiation events in
Abildgaardieae, investigate whether C4 and C3 lineages occupy similar niches,
assess levels of niche conservatism, and provide knowledge on how C3 and C4
lineages have differentially responded to environmental changes in Africa. In
combination with identification of key lineages and habitats for conservation, this data
will inform on-the-ground plant conservation in Africa. Abildgaardieae (in particular
Bulbostylis) have been chosen as a focus groups for the Kew Science Strategic Output
programme Tropical Important Plant Areas (TIPAs; http://science.kew.org/strategicoutput/tropical-important-plant-areas) as they are capable of informing ecosystem
based conservation where wetlands, temporary wet habitats, metal-rich soils,
inselbergs and submontane grasslands are concerned.
For more information on how to apply visit us at www.imperial.ac.uk/changingplanet