Rothamsted Research

where knowledge grows

Cropping Carbon

The UK has an ambitious target of 80% reductions in greenhouse gas emissions by 2050. We will aim to provide renewable and sustainable alternatives for fossil fuel-based products and to translate these into robust technologies and practices that can be used by policymakers, agribusinesses and energy companies to help underpin the UK's transition to a low carbon economy and contribution to future energy security and mitigation of global climate change.

This strategic theme will be delivered through three programmes:

1. Maximising carbon harvest. We will study the genetics, biochemistry, physiology and agronomy of carbon flux in Willow and Miscanthus, and exploit the unique knowledge developed at Rothamsted on genetic regions in Willow associated with high biomass and energy production (1). At the biochemical level, the pathways and flux of fixed carbon in these highly productive lines will be analysed using metabolomics (2,3). Our ability to cross and select improved willows using conventional breeding, underpinned with molecular marker technologies, provides a delivery route to industry, whilst Willow transformation is being developed to provide a rapid means of testing the function of potentially useful genes.

2. Increasing carbon retention. We will study the potential to increase carbon stocks in agricultural soils by using our long-term trials in perennial energy crops, particularly exploiting the C4 physiology of Miscanthus and the Highfield reversion experiment where wheat, grass and fallow land-use has been monitored since 1949. At our North Wyke site, we will investigate potential carbon sequestration in soils at the molecular level using the analyses of plant biomarkers and compound-specific stable 13C isotope ratio mass spectrometry. The carbon cycle in soils is a continuum of “above ground” and “below ground” plant biomass deposition and relatively little is known about what controls the residence time of carbon in soils between these two end points. Understanding the contribution of roots to sub-soil carbon stocks and the underlying biogeochemical processes for carbon stabilisation in deep soils may inform strategies for enhanced sequestration of carbon (4, 5).

3. Integrating carbon systems. We shall examine patterns of carbon fluxes between sources and sinks in different perennial cropping systems by developing models to assess interactions between “above ground” and “below ground” plant biomass. We will take into account not only carbon used in growth of the living plant, or stored in reserves, but also secondary metabolites and losses through soil litter, volatiles and exudates. These models are highly relevant to the farming industry and land use planning (6) where the entire carbon (and nitrogen) flux of a farm operation must be optimised. In the future, based on such calculations farmers could access carbon credits for new land use practices, which markedly improve their overall carbon footprint compared to standard procedures.

References

1. Brereton, N. J., Pitre, F. E. Hanley, S. J., Ray, M., Karp, A. & Murphy, R. J. (2010) Mapping of enzymatic saccharification in short rotation coppice willow and its independence from biomass yield. Bioenergy Research 3, 251-261. DOI: 10.1007/s12155-010-9077-3

2. Bino, R. J., Hall, R. D., Feihn, O, Kopka, J., Saito, K., Draper, J., Nikolau, B. J., Mendes, P., Roessner-Tunali, U., Beale, M. H., Trethewey, R. N., Lange, B. M., Wurtele, E. S. & Sumner, L. W. (2004) Potential of metabolomics as a functional genomics tool. Trends in Plant Science 9, 418-425. DOI: doi:10.1016/j.tplants.2004.07.004

3. Ward, J. L, Baker J. M & Beale, M. H. (2007) Recent applications of NMR spectropscopy in plant metabolomics. FEBS Journal 274, 1126-1131. DOI: 10.1111/j.1742-4658.2007.05675.x

4. Dungait, J. A. J., Docherty, G., Straker, V. & Evershed, R. P. (2011a) Variation in bulk tissue, fatty acid and monosaccharide d13C values between autotrophic and heterotrophic plant organs. Phytochemistry 72, 2130-2138. DOI: 10.1016/j.phytochem.2011.07.010

5. Dungait, J. A. J., Kemmitt, S. J., Michallon, L., Guo, S., Wen, Q., Brookes, P.C. & Evershed, R. P. (2011b) Variable responses of the soil microbial biomass to trace concentrations of 13C-labelled glucose, using 13C-PLFA analysis. European Journal of Soil Science 62, 117-126. DOI: 10.1111/j.1365-2389.2010.01321.x

6. Karp, A. & Richter, G. M. (2011) Meeting the challenge of food and energy security. Journal of Experimental Botany 62, 3263-3271. DOI: 10.1093/jxb/err099