Crop varieties and agricultural practises developed as part of the Green Revolution have contributed to feeding the population growth of the 20th century. However, some of these practises are not sustainable because they are detrimental to the environment. In particular, high yield cereal crop such as wheat have benefited from the application of nitrogen fertiliser generated through the Haber-Bosh process, which produces large amount of greenhouse gases. In addition, the application and uptake of nitrogen in the field are inefficient processes, which lead to escape of nitrogen in aquatic ecosystems causing eutrophication or in terrestrial ecosystems leading to greenhouse gases volatilisation.
In order to continue producing cereal crop sustainably, it is important to grow crop varieties that can produce high yield with lower need for nitrogen application. Within the Crop Molecular Physiology group, we conduct research aiming to understand nitrogen responsiveness at the gene, the whole plant and the plot level, and to exploit this knowledge to select varieties with low nitrogen requirement. Through collaboration with Ethiopia and India, we also have an interest in millet species (e.g. foxtail millet, pearl millet and finger millet) and especially tef (Eragrostis tef).
Wheat decision: to respond or not respond to available nitrogen. (BBSRC funded- 2022-2025)
The aim of this project is to gain better understanding of the regulation of nitrogen responsiveness and how it is dampened under increasing nitrogen availability, in a crop relevant to worldwide food security. Our key hypothesis states that the intrinsic plant nitrogen status under increasing nitrogen availability promotes the down-regulation of nitrogen responsiveness. We propose to use a combination of genetics, molecular biology and physiology approaches to investigate nitrogen responsiveness in wheat. In particular, we will pinpoint the role of strigolactone in wheat nitrogen responsiveness and its downregulation under increasing nitrogen availability.
Exploiting novel wheat genotypes for regenerative agriculture (TMAF funded- 2022-2028) Co-I with Dr Nathan Morris (NIAB- Farming System).
One of the main challenges facing arable farmers is to produce high quantity and quality grain with low enough input to maximise profits, and limited negative environmental impacts. However, the current wheat varieties available to growers tend to be tested under high input conditions and under intensive cultivations methods. As part of the new farming system at NIAB, we have tested the effect of regenerative agronomic methods on soil health. Separately researchers in the Pre-Breeding Department have developed new wheat pre-breeding lines with increased genetic diversity. Here we propose to bring these two sets of expertise together in a joint project to identify solutions leading to lowering the environmental effect and cost of wheat production. Assessing new diverse wheat lines under regenerative agricultural practices will provide useful information for the development new wheat varieties.
Past team members
- Nick Fradgley (iCASE DTP PhD student, graduated 2023)
- Alek Ligeza (part time team member)
- Fatima Rasool (Visiting PhD student- March-July 2022)
- Anya Heathcote (2020-2021, Year in Industry student from University of Nottingham)
- Vijay Rajamanickam (2020-2021, Newton Bhabha Fellow, PhD Placement Programme)
- Violette Pepper (2020, Summer student funded through the Genetics Society)
Bandyopadhyay T, Swarbreck SM, Jaiswal V, Gupta R, Bentley AR, Griffiths H, Prasad M (2022) Grain number and genotype drive nitrogen-dependent yield response in the C4 model Setaria italica (L.) P. Beauv. Journal of Advanced Research.
Fradgley NS, Bentley AR, Swarbreck SM (2021) Defining the physiological determinants of low nitrogen requirement in wheat. Biochemical Society Transactions. BST20200282.
Swarbreck SM (2021) Phytohormones Interplay: Karrikin signalling promotes ethylene synthesis to modulate roots. Trends in Plant Science, 26(4):308-311.
Swarbreck SM, Mohammad-Sidik A, Davies JM (2020) Common components of the strigolactone and karrikin signaling pathways suppress root branching in Arabidopsis thaliana. Plant Physiology, 184:18-22
Swarbreck SM, Wang M, Wang Y, Kindred D, Sylvester-Bradley R, Shi Weiming, Varinderpal-Singh, Bentley AR, Griffiths H (2019). A roadmap for lowering crop nitrogen requirement. Trends in Plant Science 24 (10), 892-904.