Deputy Head of School of Biosciences, Professor of Agronomy
Debbie's research focuses on crop physiology and its application to improved crop management. Current projects include:
- Improving harvesting and processing efficiency of vining peas through prediction of yield and quality
- Improving elderflower production
- Exploring the potential of giant swamp taro as a future staple food
- Impact of tillage and crop residues on soil structure and crop production
- Novel traits for pest and disease tolerance in sugar beet
Crop physiology; agronomy; sustainable agriculture
I lead a number of undergraduate and masters level modules;
Field Crops: a week long field course based on visits to growers and applied research facilities
Plant Physiology: from cell to crop
Principles of Crop Science
I also contribute to a number of other modules such as Statistics and Experimental Design for Bioscientists, Grassland Management and Contemporary Agricultural Systems.
My research interests fall within two main areas; crop physiology and sustainable agriculture. Current and recent research includes:
- Improving harvesting efficiency of vining peas through prediction of yield and quality
Funded by Innovate UK and PGRO (Processors and Growers Research Organisation) this Knowledge Transfer Project (KTP) is using a combination of crop modelling and earth observation data to improve the prediction of harvest date and yield of vining peas.
- Novel traits for pest and disease tolerance in sugar beet
This KTP project (funded by Innovate UK and the British Beet Research Organisation) is developing tools to identify traits related to tolerance /resistance to the major sugar beet pests and diseases. By the end of the project we will produce a variety selection tool that enables growers to identify the most suitable varieties for their needs. In addition, we will share our results with plant breeders who may wish to incorporate the traits identified within their selection programmes.
A long term research experiment has been set up at the University of Nottingham's Farm to investigate the impact of cultivation strategy and residue retention on soil physical properties crop growth and yield and greenhouse gas emissions.
In a separate project, we are investigating the effect of cover crops on soil structure and on the growth and yield of the subsequent crop. This work combines detailed experiments in the glasshouse with replicated field experiments and on-farm measurements
XIE, Q, FERNANDO, KMC, MAYES, S and SPARKES, DL, 2017. Identifying root architectural traits associated with yield and yield components in wheat Annals of Botany. 119(7), 1115-1129 TOWNSEND, T.J., SPARKES, D.L. and WILSON, P., 2016. Food and Bioenergy: Reviewing the Potential of Dual-Purpose Wheat Crops. Global Change Biology: Bioenergy.
QUAN XIE, SEAN MAYES and DEBBIE SPARKES, 2015. Carpel size, grain filling, and morphology determine individual grain weight in wheat Journal of Experimental Botany. 6715-6730
- Understanding soil-plant interactions to improve sugar beet productivity.
This five year programme, funded by the British Beet Research Organisation, is divided into three work packages:
1.Evaluating and mitigating limitations to water uptake: A range of techniques, including X-ray CT imaging of intact soil cores, will be used to identify limitations to water uptake by the sugar beet crop. Field experiments will then explore strategies to overcome the most important limitations to water uptake, thereby increasing water availability for crop growth and enhancing yield.
2.Identifying rooting traits for optimal nutrient uptake: This work package will evaluate the diversity in rooting traits in UK and European sugar beet germplasm and explore relationships between rooting traits and nutrient uptake. The aim is to develop a rapid rooting screen for nutrient uptake efficiency. Allied to this work, and informed by the rooting traits associated with improved nutrient uptake, will be field experiments to evaluate nutrient placement techniques.
3.Improving establishment and early growth: The third work package will investigate soil physical properties at drilling (e.g. aggregate size, bulk density, shear strength, moisture content) and their relationship with emergence rate and final plant population. Data collected from a field survey across a range of soil types, will be used to develop a model that uses soil physical properties, plus environmental information (e.g. soil texture, temperature etc.) to predict establishment. The model will be validated across soil types and seasons before being used to develop a tool that growers can use in-field, to predict establishment rate, based on seedbed quality. The tool will facilitate grower decision making regarding the required seed rate or whether to improve establishment by, for example, carrying out additional cultivations.
Exploiting resource use efficiency and resilience of ancient wheat species. A combination of early domestication of crop plants and modern plant breeding has led to reduced genetic diversity in crop species compared to their wild progenitors making them more susceptible to biotic and abiotic stresses. This narrow gene pool makes it difficult to select for crop varieties that perform well in harsh environments. Landraces and progenitors of modern genotypes could provide the genetic diversity required to maintain genetic progress of crops such as wheat. Preliminary data indicates that spelt has a higher radiation use efficiency than bread wheat, and that emmer may have a higher water use efficiency. This project tested the preliminary data collected by repeating the evaluation of the ancient wheat species in terms of radiation capture and conversion (fractional interception, biomass production, radiation use efficiency, harvest index and grain yield) to see whether these trends are consistent across seasons and growing conditions. The experiment will compare spelt, einkorn and emmer with a range of elite varieties of wheat currently in use in the UK. In addition, water use efficiency, N uptake efficiency and N utilisation efficiency were be examined.
- Bioenergy from wheat straw. Wheat straw represents a potential source of biomass for the production of liquid transportation fuels to replace petrol. However, wheat needs to be optimised for several key parameters to make this process more effective. A wide range of wheat germplasm (elite cultivars, advanced breeding lines, mutant populations) were characterised for biomass production, partitioning between grain and straw, and cell wall deconstruction and subsequent fermentation to ethanol.
- Modelling the impact of climate change on UK wheat production
During a recent sabbatical at CSIRO in Australia, I validated the APSIM wheat model for use in the UK and then used APSIM to investigate the impact of climate change on UK wheat production.