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.

There is a large and growing market for plant-based protein, within which the imperative for price competitiveness and sustainability continues to drive a major shift in preferred raw material from soybean and pea to faba bean. Prior UKRI funded research by the applicants has developed faba bean genome maps and uncovered sequence variation controlling a variety of simple and complex faba bean seed traits including, crucially to this application, levels of anti-nutrients as well as nutrients in the seed. The team has thus secured a world-leading position in understanding the genetic architecture of faba bean seed storage protein content and composition. They have already laid the foundations for commercial exploitation of this knowhow by conducting market research into the demand for faba bean varieties with enhanced protein content, quality or both (the 'Fabaplus' concept), by generating novel nutritionally enhanced breeding material and validating cutting edge methodologies for selection of commercially viable candidate varieties with uniquely high content and high quality of seed protein. However, the long duration of the breeding process and uncertainties over which characteristics other than seed nutritional density/quality might be decisive in determining the commercial success of a putative 'Fabaplus' variety mean that it is difficult for commercial bean breeders to invest in the concept as it currently stands. Therefore, it is appropriate to request UKRI support for a development plan which will take the 'Fabaplus' breeding pipeline to the point where novel candidate lines with both competitive yields and unique quality characteristics can be evaluated for their technical performance by commercial partners in their plant protein concentration processes. The programme essentially involves scaling up efficient DNA and protein profiling of 1,000s of individual lines from breeding populations, so that we can stack beneficial DNA variants and process a sufficiently large population to find rare individuals combining competitive commercial yield potential with unprecedented levels of high-quality protein. To assess the utility of 'Fabaplus' trait enhancements, we have partnered with a plant protein processor who has specifically targeted faba bean as a raw material fitting the sustainability and nutritional values required by their business models. Our processor partners will conduct side-by-side evaluations of 'Fabaplus' candidate varieties alongside best current commercially available raw materials to determine any gains in efficiency or end product quality attributable to the raw material, forming the basis for an assessment of economic returns that will drive demand for 'Fabaplus' varieties. Two alternative routes to commercialisation are envisaged: either a dedicated new spinout company will be formed to finish and submit 'Fabaplus' varieties for Plant Breeder's Rights or the further breeding and commercialisation will be pursued through partnership with commercial breeders under a licensing arrangement. An advisory board of commercial bean breeders and end user partners will provide ongoing feedback throughout the programme and a forum through which optimum commercialisation routes can be developed

Turnip yellows virus (TuYV) is a damaging pathogen severely reducing yields of oilseed rape (OSR) (3rd most widely grown crop in UK). UK losses are estimated at >15%, costing £69 million/annum. It also significantly reduces the yield (up to 65%) and quality of brassica vegetables (e.g. cabbage and sprouts). In earlier BBSRC-funded research, we identified sources of natural plant resistance to TuYV that were effective against the different strains of TuYV. The aim of the proposed research is to work together with commercial plant breeders from different companies to provide plant lines with our resistances to TuYV and tools (molecular markers) needed for our commercial partners to move the resistances in to commercial OSR and vegetable brassica crop varieties. The breeding of the virus-resistant varieties will increase yields, thereby helping food security and also reduce the amounts of pesticides farmers spray on crops, in attempts to stop the greenfly vectors spreading TuYV

Use of host resistance is the most effective and environmentally friendly way to control plant diseases. Oilseed rape (Brassica napus) is an important arable crop in the UK. The disease phoma stem canker, caused by Leptosphaeria maculans, poses an increasing threat to sustainable production of this crop. In the UK, phoma stem canker cause losses of > £100M p.a., despite use of fungicides. These losses will increase if the most effective fungicides are no longer permitted by EU legislation. Furthermore, it is predicted that global warming will continue to increase the range and severity of phoma stem canker epidemics. There is thus a challenge to produce cultivars with effective resistance in a changing climate to contribute to national food security. This project aims to decrease future risk of severe phoma stem canker on oilseed rape by developing a scheme for effective use of host resistance and by improving understanding of operation of host resistance against the pathogen to guide resistance breeding. The two types of resistance to L. maculans identified in B. napus are major resistance (R) gene mediated qualitative resistance that operates in cotyledons and leaves in autumn and quantitative resistance that operates in leaf stalk and stem tissues, after initial leaf infection until harvest in summer. R gene mediated resistance to L. maculans is single-gene race-specific resistance that is effective in protecting plants only if the corresponding avirulent allele is predominant in the local L. maculans population. R gene resistance often loses its effectiveness in 2 to 3 years after widespread use in commercial cultivars because of changes in L. maculans populations. To maintain the effectiveness of R gene resistance and decrease the risk that it will become ineffective, races in L. maculans populations in different regions will be determined. The L. maculans race information will be used to develop a scheme for deployment of cultivars with different R genes in space and time. Previous work at Rothamsted showed that temperature influences the effectiveness of both R gene resistance and quantitative resistance against L. maculans. To identify effective resistance in oilseed rape that will operate against L. maculans in a changing climate, this project will assess effectiveness of different types of resistance in both in controlled environments and natural conditions. Cultivars with only R genes, only quantitative resistance or combinations of R gene & quantitative resistance will be tested in different environments. From the results, we can assess which R gene or which combination of resistance is more effective. This information can be used to improve breeding strategies. To understand how temperature influences the effectiveness of host resistance, this project will focus on the three R genes which show a differential response to temperature; two of them map in the same region on chromosome A10 at distinct loci. To investigate mechanisms of operation of R gene and quantitative resistance against L. maculans, sets of materials with these R genes in the same background or the same R gene in different backgrounds will be used. These materials will enable us to investigate whether the difference in temperature response between these three R genes is due to the resistance loci or host background. Results from this project will help to minimise the risk of severe epidemics on oilseed rape so that yields are maintained to contribute to national food security and avoid unnecessary fungicide use. Breeders will benefit from improved strategies for breeding cultivars with effective disease resistance. The environment will also benefit from reduced greenhouse gas emissions through improved disease control in oilseed rape.

Although oilseed rape (OSR; Brassica napus) has traditionally been grown as the most profitable break crop, a loss of controls for cabbage stem flea beetle (CSFB; Psylliodes chrysocephala), has resulted in UK cropping area declining by 35% between 2012 and 2019. The National Farmers Union (NFU) estimate the removal of neonicotinoid seed treatments has cost farmers ~£94 million/year in lost opportunity and crop loss. Additional costs have been absorbed by the UK crushing industry because of the need to import OSR. Collectively, this poses a serious risk to the viability of the UK OSR industry and current farm crop rotation practices. With the withdrawal of chemical controls, resistant cultivars are central to supporting Integrated Pest Management (IPM) strategies. However, unlike plant-pathogen interactions, our understanding of the interactions between host plants and chewing insects is limited. CSFBs are attracted to glucosinolates, chemicals used by Brassica species to deter non-specialist insect pests. Even if B. napus has defence or resistance mechanisms that deter CSFB feeding, the genetic control of such mechanisms and whether they can be exploited to breed for resistance has remained an open question. There are no known examples of resistance in B. napus and little knowledge of resistance mechanisms within our UK crop species. No resistant cultivars are currently available for any insect pest of OSR. This proposal builds on preliminary data using controlled feeding studies and field trials, which shows that variation for reduced adult CSFB feeding is present within a diverse panel of B. napus. The panel, comprising historical varieties of winter and spring OSR, Chinese OSR, swede and kale, contains genetic diversity which is unlikely to be present in elite cultivars. This has enabled us to identify loci associated with CSFB feeding damage. Controlled larval infestation studies within this population have also identified variation in the numbers of emerging adult CSFB, demonstrating the presence of resistance to CSFB larvae. Together these observations indicate that some varieties of B. napus carry genes which can 1) deter adult CSFB feeding and 2) confer resistance against larval infestation or reduce larval fecundity. If identified, this variation can be exploited to breed OSR resistant to both damaging stages of CSFB. This proposal developed by two research institutes (JIC and Rothamsted Research), seven major plant breeders and the OSR growers' Levy board (AHDB), aims to discover loci associated with adult CSFB feeding and larval resistance in B. napus. In parallel, we aim to develop an understanding of crop adaptations which affect OSR-CSFB interactions. This will be coupled with larval development studies, gene expression analysis and metabolite profiling to further elucidate key mechanisms by which Brassica plants identify and defend themselves against beetle attack. Key genes implicated in resistance and defence responses will be investigated using candidate gene studies in model plants, including candidate genes which underlie two loci implicated in the supporting data. Collectively, this knowledge, combined with germplasm and markers that will be used by participating breeders to integrate resistant alleles into commercial breeding pipelines, will facilitate the introduction of tolerant varieties into the UK OSR market.