Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 225.97K | Year: 2011
This proposal for LINK funded project will build on a solid base of work currently underway, funded through existing LINK programmes, BBSRC, directly by industry, the Scottish Government and the NIAB Trust fund. The proposed study will seek to initiate a better understanding of wheat root growth, morphology and functional relationships with nutrient and water uptake. Methods to describe roots in a diverse range of winter wheat types will be implemented in controlled glasshouse conditions and in the field. The project will form the foundation for improving nutrient sequestration and conversion in this important UK crop through initiation of pre-breeding and development of ideal root ideotypes suitable for use in current and future wheat production. The consortium will concentrate on efficient or enhanced use of resources, especially nitrogen and phosphate and will consider interactions with water availability. In addition, the importance of interactions with beneficial mycorrhizal fungi on nutrient sequestration and the negative impact of soil-borne pathogenic fungi on susceptible genotypes will be considered under field conditions. Finally, the potential impact of agrochemical seed coats on root performance will be assessed. Overall, research in root biology leading to increases in nutrient uptake efficiency will contribute to reductions in diffuse pollution and will substantially reduce green house gas emission due a reduction in the use of nitrogen fertilisers in wheat cultivation
Agency: GTR | Branch: Innovate UK | Program: | Phase: Collaborative Research & Development | Award Amount: 28.97K | Year: 2010
Take-all is one of the most important fungal diseases of UK winter wheat, with up to half the crop being affected with losses costing farmers up to £60m per annum. The disease causes root system damage, resulting in reduced water and nitrogen uptake, which impacts on both yield and quality. Current control measures are not 100% effective and include cultural practices and chemical control. Previous work at Rothamsted Research has shown that the varieties Avalon and Cadenza show differences in the amount of the take-all fungus left behind in the soil after harvest. This influences the inoculum available for infection of a second wheat crop. The genetic loci controlling this trait have been identified and the aim of this project is to utilise these results in developing varieties which resist take-all build up (TAB). The 1st objective will be to assess a further range of UK varieties and lines from the partners with respect to this take-all build-up phenotype. The 2nd objective will be to map the genetic loci further, using more lines from the Avalon x Cadenza WGIN mapping population. From this analysis we aim to map this trait more finely in order to give us diagnostic markers for use in marker-assisted selection (MAS). During this project, we will have selected varieties and advanced material for direct use in the market place which show this reduced TAB phenotype, giving added value to material currently entering registration. Development of UK varieties carrying this unique trait will benefit not only our companies, but also wheat productivity by increasing yields by up to 1.9m tonnes pa.
Agency: GTR | Branch: BBSRC | Program: | Phase: Studentship | Award Amount: 0.00 | Year: 2015
Wheat, grown on more land than any other crop, is the most important food grain source for mankind, it provides 20% of our calories, is the major source of protein for the poor, and is by far, the major European crop. Fusarium head blight (FHB) is a major threat to wheat production. FHB reduces yields and leads to the accumulation of mycotoxins in grain. Most UK wheat varieties are highly susceptible to FHB and achieving resistance remains a major challenge internationally. Traditionally, research has focussed on identifying FHB resistance and introgressing genes of major effect into commercial varieties. In this project we aim to exploit our discovery that wheat is complicit in its own downfall. This is because carries FHB susceptibility factors that actually assist the fungus. This finding means that a new approach can be taken - the targeted elimination of susceptibility. We have identified three locations in the wheat genome that confer susceptibility to FHB. The aim of this project will be to physically map these regions with the long term intention of isolating the genes responsible. A pre-existing gamma-irradiated population of a FHB susceptible wheat cultivar will be used to generate a deletion map of the target regions. Previous studies have established the deletion frequency within these materials. A tiling path of overlapping chromosomal deletions covering the FHB susceptibility loci will be constructed and used to dissect each of them by putting together genomic and FHB resistance data. In this way the position of the FHB susceptibility factor will be refined. The gene content of the newly defined loci will be revealed by alignment of deletions to closely related cereal species for which genome sequence is available (gene content prediction by synteny) and increasingly by the more direct comparison with the rapidly emerging wheat genome sequence. These approaches will allow the identification of candidate FHB susceptibility genes, which will then be studied in detail for expression profiles. If time permits wheat TILLING populations will be screened to identify and disease screen mutants in the susceptibility factor candidates. In addition to providing an outstanding opportunity to work at the forefront of crop science, this project includes collaboration with a dynamic wheat research team with the company RAGT to provide the student with an insight into commercial plant breeding.
Agency: GTR | Branch: Innovate UK | Program: | Phase: Collaborative Research & Development | Award Amount: 28.51K | Year: 2010
Arbuscular mycorrhizas are an ancient symbiosis between land plants and fungi in which the fungal partner provides the plant with inorganic nutrients from the soil in return for carbon fixed from the atmosphere by photosynthesis. In addition there is increasing evidence that mycorrhizal fungi induce broad spectrum resistance against pathogens, so suppression of these associations by breeding and management practices may have lost the benefits of this symbiosis. Currently commercial wheat varieties have been selected to have very high yield potential and adequate disease resistance when grown in modern high intensive, short rotation systems. Positive selection for the ability to form a mycorrhizal association is therefore unlikely to occur. The project is investigating the differential responses of wheat cultivars to mycorrhizal colonisation that could provide a new source of resistance to pathogens. Once differential responses to mycorrhizal colonisation have been indentified, the genetic elements controlling responses will be genetically marked to enable the trait to be introduced into commercial germplasm.
Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 149.53K | Year: 2010
Fusarium head blight (FHB) of cereals is caused by a number of fungi, chiefly Fusarium species. It is of particular concern because the Fusarium species produce trichothecene mycotoxins (DON, NIV, T2 and HT-2) within grain that are harmful to human and animal consumers. FHB disease poses an increasing threat to the UK wheat and barley crops. New species have appeared and spread in the UK for which climate change may, in part, be responsible. Future predicted climate changes are likely to exacerbate risks of epidemics in the UK. The EU recently set limits for DON and limits for T2/HT-2 are imminent. It is vital that the UK is positioned to be able to comply with this legislation. It is widely recognised that resistant varieties offer the best option to control FHB. All wheat and barley breeders consider it as a major but difficult target for resistance breeding. Incorporation of high levels of resistance to FHB into wheat and barley will be critical to prevent DON, T2, HT-2 and NIV mycotoxin contamination of grain from becoming a major problem for all elements of the UK food and feed chains. Timely application with appropriate fungicides can restrict disease development and mycotoxin accumulation. Under moderate to high disease pressure, however, fungicide application often fails to reduce DON contamination to below EU legislative limits in susceptible varieties such as those currently grown in the UK. Our previous work showed that much of the susceptibility of UK varieties is due to linkage between a gene that affects the height of wheat, Rht2 (also referred to as Rht-D1b) which is in almost all UK varieties, with a gene nearby on the chromosome that increases susceptibility to FHB. This association must be broken to enable breeders to produce FHB resistant varieties with acceptable agronomic characters. The project will produce molecular markers to the region about Rht2 allowing plant breeders to maintain this agronomically important gene in their breeding programmes while selecting against the linked FHB susceptibility factor. This project aims to identify resistance to Fusarium head blight (FHB) in wheat and barley that will function against all the causal fungi associated with this disease. This project will focus on the identification of Type 1 resistance (resistance to initial infection) in wheat and barley. We have developed new tools to characterise so-called Type 1 resistance (resistance to initial infection), which is important for preventing infection of wheat and barley against Fusarium species that produce DON mycotoxin and those that produce the more toxic T2 and HT-2 toxins as well as against non toxin producing FHB pathogens such as Microdochium species. Plant breeding companies can immediately use the plant materials, genetic knowledge and molecular markers linked to FHB resistance within their breeding programmes to produce new resistant varieties with good characters for growing as crops in the UK. This project will determine how fungicide application influences disease and toxin accumulation in varieties with different levels of FHB resistance. The project will demonstrate how individual FHB resistances affect the RL disease score, revealing how many, and what forms of resistance are required to ensure that toxin levels in UK grain do not exceed EU limits. The project will identify the components required to establish a sustainable, integrated approach to ensure that toxin levels in cereal grain remain below EU limits. An integrated approach, based on varieties with significantly enhanced resistance and appropriate fungicide application offers the best means to achieve sustainable control of FHB and minimise the risk of mycotoxins entering the food and feed chains.