Globally, onions are the second-most popular vegetable, with production at 99Mt p.a. In the UK, they are the fourth-most consumed vegetable and growing in popularity, given recent resurgences in the perceived health benefits of eating vegetables and enthusiasm for home cooking. Whilst it might be anticipated that the UK onion industry (based primarily in eastern England), would be thriving, this is not the case. Home-onion production fulfils less than half of the UK's demand (≈800kt p.a.), with the deficit made up by imports over approximately three months, associated with greater-environmental impact and higher-overall prices. The situation has been exasperated by recent-hot summers, seeing onions go unirrigated in favour of other crops, resulting in a 20%-yield reduction. Defra anticipates this trend to continue and growers are under intense pressure to increase productivity and regain import trade and in so doing, reduce waste, crop-input losses and transport impacts in a transition to net-zero production. **Our vision** is to allow UK growers to grow, store and supply onions to the UK market all-year-around. Improved-crop quality is key to increased productivity, with bacterial infections being the greatest cause of crop- and storage-failures, economic losses (£8.5M p.a. farm-gate losses) and reputational damage. 'Allium Protect' follows a recent IUK SMART project, which detailed the main onion-rot bacteria and generated proof-of-concept for an **innovative, bacteriophage-based solution**; naturally-occurring, highly-specific bacterial viruses, with zero non-target effects. Bacteriophage form the basis of a low-risk biocontrol and are being pioneered by the Project Lead as Plant-Protection Products in key fresh-produce sectors. Allium Protect's **key objectives** are to build on the SMART data, addressing new **scientific- and technological-challenges** and assessing the technology's **feasibility** within **commercial-onion growing**. English growers are central to the project, led by Rix Farms/Stourgarden, producing 20% of the UK's onion crop and supplying ≈90kt for retail (including 100% Tesco's requirements). 'Allium Protect' **aims** to optimise a pilot-bacteriophage mix from the earlier SMART project, assess its efficacy in preventing crops from field-infections and subsequent in-store breakdown. Key academic knowledge exchange will detail the full onion-growing environment microbiome and any impacts of bacteriophage on the dynamics within it. Success will provide confidence to invest in further R&D and exploitation towards full-commercialisation. The project addresses a timely opportunity given the impact of rot-induced losses on the UK onion industry. It also represents a significant opportunity for the Lead Application to reinforce its position as a major player in a rapidly-growing, global-biopesticide market.

Globally, onions are the second-most popular vegetable, with an annual production of 99 Million tonnes. In the UK, they are the fourth-most consumed vegetable and growing in popularity, with recent lockdowns increasing the publics' perceived health benefits of eating vegetables and enthusiasm for home cooking. Currently, home onion production fulfils only ≈50% of UK demand (≈800kt p.a.), with the deficit made up by imports, mainly from The Netherlands but as far away as New Zealand, associated with greater environmental impact and higher overall prices, passed onto the customer. **Our vision** is to allow UK growers to grow, store and supply onions to the UK market all-year-around, adding economic value and implementing more sustainable production methods. Improved-crop quality is key to increased productivity and this project will address bacterial-crop infections that produce significant in-store rots, resulting in crop right-offs, economic losses (£8.5M p.a.) and reputational damage. These losses tighten the UK supply, increasing the reliance on imports. To date, a lack of detailed knowledge of the relevant onion-rot pathogens has hampered the development of effective rot-disease control, with the industry having access to relatively cursory identification methods. This project's **innovation focus** lies in using new pathogen-characterisation data to target control measures, bringing both economic and environmental added value to the UK-onion sector, in addition to being applicable to the £32.8Bn global market. The **key objective** is to harness new knowledge of onion-rot pathogens to develop a sustainable, low-risk biological-control approach based on bacteriophage; naturally-occurring, highly-specific antimicrobial agents, which kill bacteria, with zero non-target effects. The lead partner has made considerable progress in developing the technology for plant protection but in relatively niche markets and with often limited pathogen characterisation extending development timelines. The biology and genetics of onion-rot pathogens and those from the wider-onion growing environment (microbiome) will be characterised, effectively creating a comprehensive library of the most prevalent and virulent onion-rot bacteria. This will act as a valuable resource for bacteriophage isolation and more focussed matching against key pathogens. The **aim** is to derive a pilot-bacteriophage formulation and investigate the feasibility of the rot-control approach, both in the laboratory, as well as in glasshouse and field investigations. The project addresses a timely opportunity given the impact of rot-induced losses on the UK onion industry and the wider global opportunity. New methods of targeted-pathogen characterisation will also enable the lead SME to maximise commercialisation opportunities, within a rapidly-growing global biopesticide market.