MAGIC Yield: Deploying MAGIC Populations for Rapid Development of Genetic Markers for Yield Improvement in Elite UK Winter Wheat

Context:
Wheat is the UK's major crop, covering 1.6 million hectares. Maintaining wheat yield is a critical component towards achieving economically and environmentally sustainable food security. To meet growing demand, wheat yields must increase; in the UK, this needs to take place against a background of unpredictable climate and reduced inputs. Delivering 'sustainable intensification' requires breeders to improve both yield and yield stability, in the face of unpredictable future environments. After a post-war period of sustained on-farm UK wheat yield increases, a result of both genetic and agronomic improvement, there has been no increasing trend in yield over the last fifteen years. Improved methods to increase the rate of genetic improvement represent a critical component of the solution.

For the first time in UK wheat research, this project utilises a powerful combination of newly available approaches and resources, allowing detection of the genetic determinants of yield at high-precision, thus enabling rapid deployment of project outcomes within the six participating industrial partners. Central is the use of our unique Multiparent Advanced Generation Inter-Cross (MAGIC) population, which combines high genetic diversity (originating from eight UK wheat varieties), and high levels of genetic reshuffling ('genetic recombination', captured via multiple rounds of intercrossing, and the generation of the resulting 1,000 progeny lines).

Project objectives: MAGIC Yield targets the genetic improvement of grain yield, the principle target for both breeders and farmers. It exploits the powerful union of high-density genetic marker coverage with a MAGIC population that captures high levels of genetic recombination and diversity, to:
(1) Identify and characterise the genetic regions in wheat controlling yield, yield components and yield stability, at high precision.
(2) Provide a molecular tool-kit with which wheat breeders can use in their breeding programs to deploy and track the regions of the wheat genome found to confer beneficial yield and yield stability.
(3) Provide the participating breeders with analysis pipelines and resources with which they can independently carry out analysis of MAGIC datasets, both within and after project duration.
(4) Use the novel molecular breeding methodology, Genomic Selection, to allow selection for yield and yield stability in the MAGIC lines, based on molecular data alone.
(5) Provide resources centered around the MAGIC population, from which future studies targeting additional components of sustainable wheat production can be undertaken.
(6) Develop and enhance interaction between the academic and industrial wheat R&D communities to ensure results and resources are effectively disseminated for the benefit of UK agriculture.

Applications and benefits:
The ability to apply modern molecular breeding approaches to precisely determine the determinants of yield and yield stability will lead to the development of new wheat varieties with improved performance. Such varieties would be of major benefit to the UK agronomy sector, helping increase wheat yields and protect against current and future threats to production from a changing climate. Promoting the UK's wheat R&D sector will help ensure the competitiveness of the agricultural sector, and support UK-based crop research and innovation. Ultimately, promoting stable and sustainable UK wheat production benefits the consumer in terms of food prices, and minimising the environmental impact of food production.

For the first time in UK wheat research, and in partnership with six industrial partners, MAGIC Yield combines recently available MAGIC biological resources (the eight parent MAGIC wheat population) and genomic platforms (high-density SNP arrays) to dissect the genetics of wheat grain yield, yield components and yield stability. This will be achieved by building upon previous BBSRC investment in the innovative UK Elite MAGIC biological resource (eight founders, three rounds of inter-mating, 1,000 progeny), and subsequent NIAB investment (90k SNP genotyping, generation of three years of yield data). These resources will be combined with emerging genomics and statistical genetic approaches, to deliver the tools and methodological approaches to precisely manipulate yield in UK wheat.

Specific objectives

(1) Genotype all 1,000 MAGIC lines using high-density genetic marker platforms.

(2) Create a high-resolution MAGIC genetic map.

(3) Collate five years of MAGIC yield and yield component phenotypic data.

(4) Undertake high-precision QTL mapping of yield, yield components and yield stability.

(5) Deliver a molecular tool-box and QTL pyramiding models for efficient deployment of beneficial yield loci.

(6) Use Genomic Prediction and Selection to develop models and markers for simultaneous selection of multiple yield phenotypes over successive generations.

(8) Provide MAGIC genetics, genomics and germplasm resources to the wider wheat R&D community.

Participation of industry ensures project aims effectively target breeder requirements, thus facilitating rapid technology transfer. The nature of the resource means that over time, layering of additional phenotypic datasets will permit genetic analysis of multiple phenotype complexes, allowing models to be built for marker-assisted selection based on 'whole-plant' agronomic performance.

As the UK's major crop, wheat produces an annual grain yield of 13 million tonnes, with a pre-processed value of ~£2 billion. This project will deliver the genetic platforms, know-how and tools to improve yield and yield stability in UK wheat. This addresses a key component of sustainable UK food production, and is positioned at the interface between crop research and its practical translation.

Ultimately, project outcomes will lead to the development of new varieties with increased genetic potential for yield, yield components and yield stability, benefiting growers and downstream users. As an indication project impact on growers, we estimate the benefit of fixing one QTL of minor effect (controlling 1% genetic variation) to be £26 million nationwide. However, project outcomes will impact upon multiple sectors:

1. Private sector wheat R&D and breeding
MAGIC Yield will underpin competitive UK-relevant wheat breeding by helping breeders develop varieties with higher yield potential and yield stability, thus enhancing their performance and marketability. Breeding a new variety requires ~7 years, and a further 2-3 years of National List trials before reaching the market. Project outcomes have the potential to be integrated into breeding programs at the end of year 2, with release of National List accredited varieties ~9 years later. By supporting the alignment of UK biosciences with industry and agriculture, MAGIC Yield will help maximise the productivity and international competitiveness of these sectors.

2. UK farmers and agriculture
UK growers will benefit from the availability of new wheat varieties with improved genetic potential for yield and yield stability (ie the ability to achieve higher and more stable yields), and the associated benefits that go with increased grain yield per unit area (ie reduced input costs, increased land use efficiency). This will help maximise resource-use efficiency and support the sustainability and competitiveness of the UK arable industry.

3. UK biosciences
MAGIC Yield deploys innovative tools and approaches to provide practical solutions to the challenges facing sustainable UK crop production. Timely release of project outcomes will prime further research using MAGIC to further dissect the genetics of wheat yield, yield protection and grain quality. Involving rapidly advancing areas of crop genetic research, this project will provide training and skills relevant to modern crop science, and help raise the international profile and impact of UK biosciences. Collectively, project resources and outputs provide a powerful community resource for the investigation of wheat genetics in UK relevant germplasm.

4. Wider UK public and policy makers
The introduction of new wheat varieties with higher yield per unit input will have downstream effects on consumers and society in general. All parties will benefit from a more stabilised marketplace resulting from greater buffering of UK wheat production against price fluctuations. The project will therefore contribute to increased food security under increasingly volatile and unpredictable economic and environmental conditions. By demonstrating the ability of scientific R&D to provide solutions to national and international policy, goals and legislation, project outcomes will help inform current and future government decision making processes on food security and biosciences.