Flora Graeca watercolour pigment analysis
Pigment analysis of one of Ferdinand Bauer's original Flora Graeca watercolours using Raman spectroscopic analysis. A collaborative research project with the Bodleian Libraries funded by the Leverhulme Trust.
More information can be found on page 4 of this article: http://www.leverhulme.ac.uk/templates/asset-relay.cfm?frmAssetFileID=1648
Rosemary Wise presented with Sibthorpe Medal
Sir Ghillean Prance FRS gave a lecture entitled A Passion for Plants: from the Rainforests of Brazil to Kew Gardens in the Department of Plant Science today, 22nd January 2015. He provided an exciting overview of his research on the floristic diversity of Amazonia in honour of Rosemary Wises's 50 years in the Department. In that time Rosemary has produced over 12,000 botanical illustrations and is currently working on Illustrations of plants in the genus Ipomoea.
Rosemary was then presented with the prestigious Sibthorpe Medal for lifetime contributions to Botany.
Forest Genomics: A major partnership between Université Laval and Oxford University
As part of an economic mission taking place in Europe, Prime Minister Philippe Couillard announced in London a scientific and academic partnership between Université Laval and Oxford University. The objective of this partnership is to create an international consortium in forest genomics.
Spearheaded by Professor John MacKay, a world-renowned expert in the field, Wood Professor of Forest Science at Oxford University, the consortium will address the major scientific challenges involving the productivity and sustainability of both natural and managed forests. Expected outcomes include improved health and productivity of forests and their sustainable management. This partnership represents a major opportunity for Québec and Canada.
More details from: http://www.genomequebec.com/208-en/news-forest-genomics-a-major-partnership-between-universite-laval-and-oxford-university.html
Special seminar about "the father of genetics", J. G. Mendel
Plant Sciences were privileged to hear a special seminar about "the father of genetics", J. G. Mendel, given by the Augustinian Abbot Mr Evzen Lukas Martinec. Abbot Martinec is the 6th direct successor of Mendel in the Old Brno Abbey in the Czech Republic.
The talk described Mendel's life, reasons for joining the Augustinian Order, his wide interest in natural sciences, and his lack of recognition for his unique discoveries with plant hybridisation during his life.
This seminar marked 150 years since Mendel's first public presentation of his work.
Case Study: Combating forest destruction through tree genetics
Forests are of great ecological importance: they shape the landscape, help to control erosion and water filtration, and provide habitat for large numbers of other species. In addition they provide us with wood, a highly important natural resource, making trees as valuable a crop as many of those that are grown for food. In the northern hemisphere natural forests are often 'harvested' for their wood, and new plantations established to replace the logged trees. As with any other crop, there is an increasing need to select strains of trees which are as productive as possible and will have the best chance of thriving.
Destruction of natural forests can be both environmentally and economically catastrophic, but it is not only man who has the potential to have adverse effects on forest health: forest pests also pose a serious threat. One of the most significant North American pests is the spruce budworm, a small moth whose larvae invade the growing shoots of spruce and fir trees, causing widespread devastation. From 1950 to 1993 a spruce budworm epidemic swept across eastern Canada, covering an area of almost a million square kilometres; the pest killed up to 58% of the trees it attacked, and had a disastrous impact on wood yields.
Modelling and predicting future outbreaks is essential, but currently this is difficult to achieve. Climate change is leading to major changes in insect populations and behaviour, and although some trees are naturally resistant to spruce budworm attack, the mechanisms controlling this were previously unknown and could not therefore be incorporated into models.
However, research by Professor John MacKay and colleagues has led to a breakthrough which could well provide a key to controlling future epidemics. The group (including Geneviève Parent, Gaby Germanos and Eric Bauce at Laval University, and Melissa Mageroy and Joerg Bohlmann at the University of British-Columbia) studied a ten-year localised outbreak of spruce budworm in a population of white spruce, a commercially important tree species in North America. Resistant trees produce high levels of a chemical which is toxic to the spruce budworm larvae. Critically, the group showed for the first time that this is linked to a single gene, which encodes an enzyme that makes the toxin from other chemicals in the trees' cells. Gene expression was a thousand times higher in resistant white spruce trees than in non-resistant trees. In addition, resistant trees timed their peak gene expression to coincide with the final larval stage, in which most of the damage occurs.
Professor MacKay and colleagues have shown these traits to be heritable, which has important implications for future forest management. It means that there is now a tool for the selection and breeding of white spruce trees which are most likely to be resistant to this highly destructive pest. Previously there was no basis on which to do this, and therefore there was no guarantee that new plantations would be better at surviving an epidemic than natural forest. The research also makes it possible to examine related tree species to see if they possess a similar protective genetic mechanism. Genomic selection of resistant strains is likely to be very much quicker than current tree breeding programmes, which can take up to 30 years to establish a successful new strain; as trees are slow-growing they require a test period of up to 15 years before desirable traits can be identified. Genomic selection can cut the test period down to 2 years and reduce the whole cycle to less than 10 years.
The impact of this research for both natural and planted forests is significant. Minimising the damage caused by such a serious pest will help to protect the environment and also have an important economic benefit by reducing serious losses suffered by the timber industry.
For more detail see: Mageroy, M.H., Parent, G.J., Germanos, G., Giguère, I., Delvas, N., Maaroufi, H., Bauce, É., Bohlmann, J., Mackay J.J. (2014) Expression of the beta-glucosidase gene PgΒglu-1 underpins natural resistance of white spruce against spruce budworm. Plant Journal, DOI: 10.1111/tpj.12699
Case Study: Helping crops to make their own fertiliser
Professor Phil Poole's research is unravelling the complex relationships that have evolved between plants and nitrogen-fixing bacteria. The results could help to solve the problem of how to feed the world's growing population.
Nitrogen is fundamental to the growth of every plant on earth. Without it, they cannot make the proteins and nucleic acids necessary for healthy development and production of seeds and fruit. Availability of nitrogen is the single biggest factor limiting the yield of all the crops grown on the planet.
Although our atmosphere is 78% nitrogen, plants cannot directly make use of this source because the nitrogen atoms are bonded strongly in pairs, making the gas virtually inert. The only organisms that are able to convert atmospheric nitrogen into usable compounds like ammonia are bacteria known as diazotrophs. Some plants such as legumes (the pea and bean family) are able to harness the abilities of these nitrogen-fixing bacteria, accommodating them in living plant cells within special root nodules, and providing them with food in exchange for ammonia – essentially making their own fertiliser. Some legumes can fix more than 200 kg of nitrogen per hectare per year.
However, farming based solely on crop rotation and organic methods can no longer feed the world. Many of our most important crops (including maize, rice, wheat and sorghum) do not have the natural ability to form relationships with nitrogen fixing bacteria, and their production is entirely dependent on man-made nitrate-based fertilisers, which are now responsible for supporting an estimated third of the world's population. Continued use of nitrates at this level is unsustainable because of the environmental impacts, including contamination of groundwater and contribution to climate change through creation of greenhouse gases. With the global population forecast to rise still further, alternatives are urgently needed.
Professor Phil Poole is an expert in the symbiotic relationships that have developed between legumes and diazotrophs. The signalling mechanisms that enable a bacterium in the soil to alert a plant to its presence and the plant to accept infection by the bacterium are highly sophisticated. Together with a team of five other laboratories, Professor Poole is working to understand the biochemistry of these mechanisms and the genes that govern them. The goal is to be able to engineer interactions between microbes and plants such as wheat, so that our key crops can become nitrogen-fixing and will no longer need to depend on artificial fertilisers.
Another aim is to improve the nitrogen-fixing capabilities of existing legume crops. Some bacteria are good at colonising legumes, but poor at nitrogen fixing, and some legumes are much better than others at 'selecting' the best bacteria to fix nitrogen. One crop in particular, the common French bean, a staple in many parts of sub-Saharan Africa, is not particularly good at adopting the 'right' kind of bacteria and so does not fix nitrogen very efficiently.
Professor Poole has pioneered a technique using a bacterial gene called lux, which can be triggered to produce luminescence. By splicing lux genes into bacteria and engineering the gene to respond to the presence of different chemicals, it becomes easy to see exactly what signalling is going on between the plant and the bacterium – the bacteria simply glow when the chemical under scrutiny is present. A similar method can be used to identify bacteria which are particularly good at fixing nitrogen, by adjusting the lux gene to create luminescence when the bacteria fix nitrogen.
Because the luminescence can be detected non-invasively as it is happening, huge amounts of time can be saved in identifying bacteria, which are good at both colonisation and fixing nitrogen, and plants which are good at selecting for these bacteria. Previously this could only be tested through crop trials of thousands of plants over long periods of time. Professor Poole's methods could enable crops like French beans to be selected or engineered to generate higher levels of ammonia and hence produce higher yields.
Historically, global population growth has been supported by discoveries that have enabled farmers to increase the amount of nitrogen available to their crops. The first breakthrough, crop rotation using beans and peas, was succeeded by fertilisers based first on guano and then on natural nitrate deposits from the Atacama Desert, until finally in the early 20th century Fritz Haber invented a process that could manufacture ammonia from nitrogen and hydrogen gases. A century on from this, Professor Poole's research could help to solve the current 'nitrogen crisis' and give us crops which are both environmentally sustainable and high-yielding.
Bacteria glow when they start fixing nitrogen. The strength of the glow shows where the strongest fixation is taking place.
Case Study: Balancing conservation and commerce in the world's forests
Research into forest ecology at the University of Oxford has helped to reconcile the competing pressures of biodiversity and economic development in many parts of the developing world.
Natural forests in many parts of the developing world are under serious threat from logging, conversion to agriculture and mining. The tension between maintaining biodiversity and encouraging economic development can become acute, and a blanket requirement to 'protect forests' is unlikely to be successful in poorer countries with limited options for income generation.
Research led by Dr William Hawthorne, an expert in the ecology of the forests of Ghana, has helped to address this problem in many parts of the world, resulting in a major impact on forestry conservation and biodiversity. In 1996 Dr Hawthorne developed ways of identifying forest plants without requiring them to be in flower or fruit, which allowed even closely related species to be easily differentiated by non-specialists. He showed how, even on a fine scale, globally rare plants were clustered in 'hotspots', while heavily-exploited timber species were clustered in different areas, and tended to be well-dispersed and not globally rare.
Realising that effective mapping of forests could enable the preservation of areas with high concentrations of rare plants, whilst allowing logging to continue in other areas, Dr Hawthorne developed three 'biological Indices':
- The Bioquality Index, based on a 'Star' system of categorising species according to rarity (Black Star species are the most globally rare), and used to identify 'bioquality hotspots'.
- The Economic Index, used to identify the distribution of commercially exploitable trees.
- The Pioneer Index, used to quantify past disturbance, based on analysis of how different species regenerate after forest damage, such as logging or fire.
These indices were applied to results from large-scale 'Rapid Botanical Surveys' to assess species richness and threats within forest communities, and such surveys have now been used to prioritise and protect biodiversity hotspots not only in Ghana but across the globe.
In Ghana, the government introduced legislation to restrict logging in line with Hawthorne's 'Star' system, and initiated a large-scale project to conserve those areas of Ghanaian forest most important for biodiversity, identified using Hawthorne's Bioquality Index. Around 2,300 km2 of forest reserves were established (13% of the total forest network) and excluded from timber harvesting. To support the project Dr Hawthorne developed a user-friendly field guide to forest plants, now widely used in West Africa; and with colleagues in the Netherlands, a comprehensive and more technical guide to all the woody plants of Western Africa. In 2009 Ghana was the first country to sign a FLEGT Voluntary Partnership Agreement, a voluntary scheme to ensure that only legally harvested timber is imported into the EU.
In Liberia, Dr Hawthorne's work has influenced mining practices. In 2010 the multinational mining company ArcelorMittal (AML) commissioned Dr Hawthorne's group to carry out a Bioquality assessment of the mountainous West Nimba region, a global biodiversity hotspot also rich in iron ore. As a result, AML made significant conservation decisions which have protected important forest sites.
Dr Hawthorne's methods have also been applied in many other African countries, as well as in Malaysia, Brunei, Mexico, Honduras, Chile and Trinidad and Tobago. His work has thus helped to reconcile the demand for the conservation of biodiversity with the need to support local agricultural and economic development in many parts of the world.
'[Dr Hawthorne's] work confirmed the biological importance of forests in northern Nimba from a global perspective. Botanical mapping … helps us to determine key areas of importance in planning our strategy for forest conservation and offsets. [The work also] identified priority species for plantation trials which are highly important to local communities who depend on these plants for medicine, food, and construction materials.'
John Howell, Environmental Adviser, ArcelorMittal Liberia
Research funded by: the Overseas Development Agency, the Department for International Development (DFID), the 6th EU Framework Programme for Research and Technological Development (EU FP6), the Oxford Martin School and others.
Survey team members establishing the precise location of bioquality hotspots in Liberia's Nimba Mountains. Photo © W.D. Hawthorne
Lorna Casselton featured in Scientific American
Lorna Casselton celebrated as one of ten top female scientists who passed away in 2014 by Scientific American:
Research Assessment Exercise 2014: Biological Science at Oxford tops rankings
The results of the Research Excellence Framework (REF) 2014 were published today and confirm the University of Oxford’s world leading position in biological sciences. We ranked top for the volume of world-leading research.
The University as a whole also ranked top with the largest volume of word leading research in the UK.
Our REF Impact case was developed by William Hawthorne and highlights the contribution Williams research has had on sustainable forestry in West Africa:
You can find out more about Oxford’s results at www.ox.ac.uk/research/research-impact/ref-2014-results.