An integrated approach to stabilising HFN in wheat: screens genes and understanding

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Pre-Harvest Sprouting and associated increases in amylase production is the number one quality issue for UK wheat breeders. Sprouting results in massively reduced seed raw- materials quality that has downstream detrimental effects on post-harvest processing of grain. Detailed crop performance data over the past decade have shown that some UK cultivars perform adequately and show few symptoms of either PHA or PMA, whereas others are more susceptible; however, the complexity of the interaction between the wheat variety (genotype) and weather conditions (environment) that affect HFN has restricted the use of field-based screens for breeding of improved varieties. This project aims to bring a multidisciplinary approach to the problem. A key aim is the development of validated 'smart screens' through which PHS or PMA can be reliably induced in controlled environment conditions. These conditions will be used to characterise the performance of existing varieties to identify material with low and high resistance to PHS and PMA. The responses of the selected varieties to conditions that induce PHS or PMA will be characterised at biochemical and molecular levels to gain a deeper understanding of the biological processes involved. This will lead to the identification of genes that may be involved in the development of low HFN, which can be correlated with genetic loci identified through screening the mapping populations. Candidate genes will be identified from studies in model species, and used to analyse functionality in relation to PHS/PMA. This will include the analysis of variation present in UK varieties and mapping populations and in wheat TILLING populations, analysis of expression patterns in relation to PHS/PMA, and development of transgenic lines for proof of function. Existing populations, and new populations generated from selected parents, will be used for mapping genetic factors that contribute to HFN, which will be induced by overhead misting in the field and in controlled conditions. A total of 10 DH populations, segregating for PHS or PMA, will be used in QTL discovery and validation. Map locations of validated QTLs and candidate genes, will be used to identify those genes most likely to underly these traits and these will be specifically targeted in the generation of genome- specific, polymorphic PCR assays for use in forward breeding. The key deliverables will therefore be an improved knowledge of the biological processes involve in PHA and PMA, and reliable phenotypic screens and validated genetic markers that can be used to select for PHS and PMA resistance in wheat breeding programmes. This project was largely instigated by the UK wheat breeding industry, with encouragement from farming, milling and end-user groups, and these organisations have been closely involved in identifying the targets and deliverables of the programme. Most of the major UK wheat breeders will contribute significant intellectual and scientific resources to this project, and will be responsible for the construction and genotyping of mapping populations and the validation of molecular markers associated with resistance to PHS/PMA. It is anticipated that project management meetings, involving all partners and stakeholders, would be held at six-monthly intervals, with meetings between the researchers held at more frequent intervals. Plant breeders will be directly involved in mapping genes and validating markers in their own germplasm, and thus will begin using project outputs even before its conclusion. Results will be disseminated to the wider scientific and wheat breeding community through a website, presentations, technical articles and scientific papers.