Defra Project: WU0128
Project Completion: September 2012
Project Leader: Miriam Gifford
Investigators: Andrew Thompson, John Hammond
Carol Ryder, Martin Sergeant, James Lynn,
Howard Hilton, Will Spracklen, Rory Hayden
A major challenge for plant and crop science is discovering ways that we can increase food production in a sustainable manner. To do this we must reduce our reliance on inorganic fertilisers and irrigation, but not to the detriment of yield.
The aim of this project is to produce tools and materials suitable for breeding new crop varieties that have improved water and nutrient use efficiency. Such varieties will help:
- to reduce water pollution and improve water availability for ecosystems
- to sustain crop production during global climate change when water is predicted to become limiting
- to reduce the demand for phosphorus fertilizers as cheap, non-renewable supplies become exhausted
- to reduce the greenhouse gas emmisions associated with the intensive use of nitrogen fertilizers
The research addresses the efficiency by which plants use a number of resources:
Globally, water is the most important factor limiting crop production. It is important to develop crop varieties that can use the available water more efficiently so that crop production can be maintained, while leaving sufficient water for domestic and industrial users and the environment. Cheap phosphorus fertilisers are currently obtained by mining rock phosphate; this is predicted to become exhausted within 60 years. Thus crop varieties that use phosphorus more efficiently will be critical for food security, and for the sustainability of rural economies that depend on the purchase of phosphorus fertilizers for crop production. Manufacture of inorganic nitrogen fertilizers is a major source of carbon dioxide emissions, and price increases for nitrogen fertilizers will continue as energy prices climb. Breeding for increased nitrogen use efficiency therefore has an important role to play in reducing nitrogen inputs.
Approaches being taken in this research project:
We will use Brassica species as model field crops to identify genetic loci and genes that control resource use efficiency. Brassicas are suitable as they are grown with relatively high inputs of phosphorus and nitrogen, and the vegetable Brassicas do recieve supplementary irrigation in the UK, particularly in the case of Broccoli and on lighter soils. Their requirement for irrigation is likely to increase as water availability declines. Brassicas provide excellent model crops because of the available genetic resources and the close relationship to Arabidopsis thaliana, the model plant with the most comprehensive genetic resources.
We will identify natural variants within Brassica and Arabidopsis that have high water and nutrient use efficiencies, and then map and identify regions of the genome (including genes) that are associated with these traits. In the future, the knowledge of genes (or markers) associated with improved resource use efficiency will be transferred to other important crops (e.g potato and cereals), and used as molecular markers to facilitate the breeding of varieties with improved water and nutrient use efficiency.
This work delivers a number of benefits:
It is directly relevant to maintaining UK food security, a major policy priority for funding councils including Defra. In addition, abstraction of water for irrigation, and diffuse pollution from fertilisers, particularly nitrogen and phosphorus, can have negative impacts on adjacent ecosystems. Breeding crop varieties that require less water and fertiliser can form part of an effective mitigation strategy for reducing diffuse agricultural pollution, and maintaining biodiversity in aquatic ecosystems. Our work thus addresses the objectives set out in the EU Water Framework Directive.