In the advanced agricultural production systems of Northern Europe, weed control in cereal crops has become one of the greatest challenges to sustainable intensification, accounting for higher yield losses and greater input costs than all other biological constraints (pests and diseases). The most problematic weeds in cereals in Northern Europe are the wild grasses, notably black-grass (Alopecurus myosuroides), which has become steadily more difficult to control over the last 30 years due to the evolution of herbicide resistance. This resistance assumes two forms: 1) Target site resistance (TSR), whereby the weeds become highly tolerant of herbicides due to mutations in the proteins targeted by these chemicals rendering them less sensitive to inhibition by that herbicide mode of action. 2) Metabolic or multiple herbicide resistance (MHR) where weeds become more tolerant of a broad range of herbicides, irrespective of their chemistry or mode of action, due to a general enhancement in the ability to detoxify crop protection agents. While TSR is now quite well understood and can be countered by the rotational use of herbicides with differing modes of action, the molecular basis and evolutionary drivers which promote MHR are poorly understood and the associated grass weeds very difficult to control using conventional methods. In this 4 year project, we propose to use a combination of molecular biology and biochemistry, ecology and evolution, modeling and integrated pest management to develop better tools to monitor and manage both TSR and MHR in black-grass under field conditions. The project represents a novel agri-systems approach, linking our latest understanding in the molecular biology of herbicide resistance to on farm monitoring and modeling based on a quantitative genetics approach to define the effectiveness of different intervention measures. Through a multidisciplinary consortium, we will integrate knowledge about MHR and TSR at the molecular and biochemical levels and relate this fundamental understanding to resistance phenotypes observed in the field. Selection and breeding experiments will examine the dynamics of selection for resistance, with the intention of determining the genetic architecture of MHR for the first time and its relation to other stresses and life history traits. Data from field monitoring and glasshouse studies will be integrated in ecological, evolutionary and management models with the ultimate aim to design novel management to prevent, delay or mitigate the evolution of herbicide resistance. Finally, the environmental and economic impacts of novel management will be explored. The project therefore has the primary goal of using state of the art approaches spanning molecular biology, weed science, modeling and agronomy to provide new resistance control measures within the life of the programme. The project is divided into 5 integrated work packages which will address the following questions 1. What are the molecular mechanisms that underpin the evolution of metabolic herbicide resistance? 2. What is the extent of the herbicide resistance problem in UK black-grass populations and what impacts is resistance having on black-grass populations and crop yields? 3. What are the genetic, ecological and agronomic factors that promote and constrain the emergence of herbicide resistance? 4. How can applied evolutionary models be used to manage herbicide resistance? 5. What are the economic and environmental consequences of novel weed and resistance management strategies? The major outputs will be: 1. A rapid diagnostic toolkit for the on-farm characterisation of herbicide resistance. 2. A resistance audit for the extent and distribution of resistance to the major herbicide modes of action in black-grass. 3. A suite of models to address key questions in the emergence and management of resistance. 4. Management recommendations, together with an analysis of their impacts.

Minimal processing adds significant value to fresh produce, however, it also increases its perishability reducing shelf life and leading to waste of the produce and the resources used to grow it. This project is aimed at post harvest discolouration, a significant cause of quality loss in a wide range of fresh produce such as sliced apple, cut cabbage and lettuce. The main issue we are addressing is postharvest discolouration of lettuce in salad packs. UK lettuce production/imports are worth £240m farm gate but the retail value of UK processed salads is £800m. However, Tesco have recently reported that 68% of their salads are thrown away; the situation is similar for other retailers. There is therefore a need to improve postharvest quality to reduce waste and deliver consistently good quality products to consumers. Modified atmosphere packaging can provide control but once the pack is opened oxygen enters resulting in discolouration. Growing conditions also influence postharvest discolouration but are difficult to control in field crops. We are proposing breeding lettuce varieties with reduced propensity to discolour as a way to address the problem. To do this we need to understand the genetics and biochemistry of discolouration. We are building on previous research we have done which identified genetic factors controlling the amount of pinking and/or browning that developed on lettuce leaves in salad packs 3 days after processing. However, we do not know what compounds or which genes are involved and we now intend to find this out by a multidisciplinary project involving three universities; Harper Adams University, Reading and Warwick, a lettuce breeding company, a lettuce grower, a salads processor and the Horticulture Development Company. We have produced a set of experimental lettuce lines which we know show differences in the amount of pink or brown discolouration they produce. We will grow and process these lettuces in a way that mimics commercial production. We will then assess the salad packs for the amount of discolouration developing over 3 days, which is the current best before date for supermarket salads. We can then link this information to the plant's DNA profile to identify genetic factors for discolouration and DNA markers which can be used by plant breeders. The same lettuces will also be analysed for compounds produced by a biochemical pathway called the phenylpropanoid pathway. This is thought to produce the pigments that cause discolouration. We know from other studies in a plant called Arabidopsis the genes which control the phenylpropanoid pathway and we have found the same genes in lettuce. We will see how these genes behave in lettuce plants that produce a lot of discolouration and ones that don't discolour. We will also see how the genes behave under different growing conditions. We can link these gene expression patterns to the amount of pinking and browning to see which genes are the key ones. Once we have done this we can look for naturally occurring versions of the genes which give a reduced discolouration. The compounds produced by the phenylpropanoid pathway influence other things such as pest and disease resistance, taste etc. We do not want to reduce the amount of discolouration by breeding but end up with lettuce susceptible to pests or with poor taste, so we will assess lines which show high discolouration or no discolouration for their resistance to aphids and mildew and for taste to see if there are any differences. There are some compounds produced by the pathway which are colourless but still provide some resistance so by knowing the genetics and biochemistry breeders will be able to carry out smart breeding. We will see if the results for lettuce hold true for other crops by seeing how the key genes behave in apple and cabbage and whether this is related to the amount of browning that develops when they are processed and look for genetic differences in these crops

A harvested wheat crop is normally assessed for several quality attributes that influence the ability of its flour to make bread and also affect the money paid to farmers by millers. One such parameter is called Hagberg Falling Number (HFN) which is an indirect measure of the properties that a loaf of bread will have. For example, wheat with low HFN will produce bread that is very difficult to slice because of sticky crumb. Therefore, millers and other end-users avoid buying wheat grain that has a HFN value below a fixed number. Low HFN wheat impacts negatively on the environment as it produces wastage and inefficient use of resources. Unlike other problems in wheat which can be corrected by agronomic practices or through disease management, HFN is heavily influenced by the environment and cannot be easily improved by these means. This is especially relevant in the UK environment as cold and wet periods during the summer are thought to reduce HFN. Therefore, the most effective and reliable way for a farmer to grow high HFN wheat is proper varietal selection. Unfortunately, it is very difficult for breeders to develop high HFN varieties due to lack of knowledge of the genes, or regions throughout the genome, which might influence HFN. Through a previously funded Defra-BBSRC project we have made important progress in understanding the variation for HFN in UK wheat varieties and have taken a first step to discovering the regions of the genome that affect this trait. Despite these encouraging results, we are still short in developing the tools that breeders require to transfer this knowledge into improved commercial wheat varieties. This projects seeks to address this limitation by developing a 'breeder's tool kit' that will assist towards this end. We have selected six regions of the wheat genome which we know are affecting HFN based on experiments conducted in the previous project. We will now hone in and develop more precise information of these regions. This will result in better defined genetic maps which breeders can use to navigate the wheat genome and focus their breeding efforts more effectively in those locations that contain genes affecting HFN. We will investigate how these regions affect agronomic traits which are of interests to breeders and farmers; such as yield and other quality characteristics. We will also combine the six regions in different combinations to better understand how they work together and if we can produce more resilient varieties that will have high HFN values independent of the weather conditions. We will also investigate the basic biology of how these regions affect HFN. Together, this information will enable UK plant breeders to develop new, more competitive varieties of wheat with reduced environmental footprint and more consistent grain quality.

Control of fertility and successful reproduction is key to grain set and thus crop yield in cereals. Self-pollinating crops tend to have lower yield capability than hybrids generated by intercrossing between elite lines. This "Hybrid Vigour" has been shown to increase yield, but also abiotic and biotic stress resistance. Hybrid crops thus provide opportunities to increase yield and productivity in a sustainable manner. However, the challenge for hybrid production is the need to avoid the natural tendency for many crops to self-fertilise prior to outcrossing, whilst ensuring effective cross-pollination for hybrid seed production. Mechanisms that control fertility in a reversible manner are critical to deliver such systems and this is a key goal for wheat breeding, since major yield enhancements are possible from hybrid wheat. Hybrid seed production also relies upon effective males to pollinate the female lines, therefore traits for optimal pollen production, viability and release are also of major importance. Wheat pollen development is particularly sensitive to environmental damage, with rapid reductions in viability post anthesis, combined with general sensitivity to abiotic stress (e.g. high and low temperature) during development. Reductions in fertility due to environmental stress are often seen in wheat crops and these can have major impacts on yield. Reproductive resilience to variable environmental conditions and abiotic stress is therefore critical to sustainable yields. This can only be delivered by detailed knowledge of pollen development and systems to regulate fertility. Deep understanding of cereal reproduction is therefore key to the development of wheat hybrid breeding systems. This proposal will address these issues by providing greater understanding of pollen development in cereals towards developing switchable systems for the control of wheat fertility, but also by identifying traits for enhanced pollen production and viability, particularly under environmental stress, which are critical for ensuring successful pollination in breeding programmes. By investigating the mechanisms behind these traits and by generating tools for breeding and selection, effective breeding to increase crop productivity and resilience will be realised. The project will use our progress in understanding cereal pollen development to develop systems for controlling cereal fertility, focussing on wheat. In addition introgression lines and breeding populations will be screened to identify traits for optimal fertilisation, including high pollen production, release and durability. These will be focused around the impact of environment, particularly temperature and day length, on pollen fertility. We will determine the benefit and stability of these traits in elite commercial germplasm, enabling their potential to be determined. We will also assess natural variation at these fertility loci and develop markers to enable these traits, which could potentially impact on fertility particularly under different environmental conditions, to be followed in breeding populations.

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.