Development of molecular markers for resistance to strawberry powdery mildew

Strawberry powdery mildew is a serious disease problem in the UK where 80% of production is under polythene tunnels, an environment more conducive to the disease. It requires an intensive fungicide spray programme to achieve effective control and availability of suitable pesticides is decreasing. The solution is resistant varieties but breeding programmes currently select for resistance using field evaluation of symptoms. This has often resulted in short lived resistance, lasting only a few seasons before the pathogen adapts.
This project will develop molecular markers to enable plant breeders to develop varieties with stronger and more durable resistance. The approach is to raise a progeny of strawberry seedlings that segregates for resistance to mildew and then develop a genetic linkage map giving good coverage of the entire strawberry genome. The map position of quantitative trait loci (QTL) associated with resistance will be located and transferable markers that are tightly linked to the resistance genes will be identified and tested in a wide range of strawberry lines to validate them and identify those most suitable for marker assisted breeding. The outcome of the project will be markers that will offer an innovative approach to resistance breeding and improve the speed, efficiency and precision, resulting in stronger and more durable resistance.