It aims to achieve durable control of major beet disease in the UK by monitoring pathogen populations to predict breakdown of resistance and advising on the need for chemical control, and to develop novel sources of genetic resistance where this is currently unavailable in adequate or vulnerable to erosion.
Virus threats are accentuated by the ongoing development of insecticide resistance and climate change. An integrated disease management toolkit is required that utilises resistant varieties and accurate disease forecasts to enable timely and appropriate applications of insecticides. This system will slow the development of insecticide resistance, thus prolonging the life of active ingredients, whilst helping to reduce the amount used.
Rhizomania has also had a major impact on the UK industry, decreasing yields by up to 70%. The development of partially-resistant varieties has been a major success, especially now that these are as high yielding as those lacking the resistance (Rz1) gene in the absence of the disease. However, the initial breeding success may be short lived, as new strains of the virus, capable of overcoming resistance, have been identified in the UK. these new strains of the virus pose a serious threat to current 'resistance' varieties. Potentially, varieties could be released that may be able to withstand these new virus strains. Their suitability for the UK needs to be assessed. If no further sources of novel resistance genes are identified, the likelihood of a future breakdown in rhizomania resistance is high. It is proposed to monitor the incidence, distribution and strain variation of the rhizomania virus. Results will inform growers of resistant varieties and provide early detection of any resistance -breaking strains.