A Systems Approach to Disease Resistance Against Necrotrophic Fungal Pathogens in lettuce

Summary: 

The fungal pathogens Botrytis cinerea and Sclerotinia sclerotiorum have similar necrotrophic lifestyles, large host ranges and cause serious disease on many horticultural crops. Both fungi can cause substantial losses on field-grown and protected lettuce crops, an industry worth almost £200M annually in the UK. B. cinerea is a particular problem post-harvest, whereas S. sclerotiorum can result in up to 50% crop loss pre-harvest. Chemical control is problematic as few actives are available, the number of sprays is restricted and timing is difficult. Moreover, the fungicides are medium to high risk for development of resistance. Development of durable resistance in the crop is a more sustainable solution, but has been an intransigent problem for breeders. The aim of this proposal is to demonstrate that a novel approach to breeding for durable pathogen resistance is possible, and that it could be used in a wide range of horticultural crops affected by these promiscuous pathogens. We will utilize a systems biology approach (successfully deployed in the model plant Arabidopsis) and combine this with quantitative genetic studies in lettuce to identify novel genes for increasing the resistance of lettuce to both B. cinerea and S. sclerotiorum. This project will provide a foundation for developing similar resistance to these pathogens in other horticultural crops.