Breeding for physical resistance traits - protecting soft fruit crops from pests and pathogens

This project aims to understand and utilise plant physical mechanisms for resistance to pest and diseases in soft fruit/bush crops, to overcome changes in EU Directive 91/414/EEC and WFD and satisfy consumer demand for residue free, high quality fruit grown in the UK. Fresh fruit accounts for a market of £4 billion in the UK, and soft fruit/berries account for 17% of this. UK raspberries have a value of £94 million, strawberries £196 million, blackcurrants £12 million and blueberry, currently a minor player has a value of £95 million. Demand for UK grown fruit is increasing dramatically, however few high quality soft fruit varieties are available with adequate pest and disease resistance due to the focus on fruit quality by the major commercial fruit breeding companies.
For production to be sustainable, a greater understanding of plant-derived resistances to pests and diseases is required that can be deployed in IPDM programmes to reduce reliance on chemicals but still produce high quality fruit. Physical resistance traits are particularly promising for crop protection because they tend to be more robust against pest and disease adaptation, and unlike chemically-based resistance traits, are less likely to adversely affect fruit quality. This work aims to look at root architecture and morphology, leaf trichomes, cane/stem architecture and plant habit to determine how variation in these physical traits contributes to resistance against major soft fruit pest and diseases. Using the raspberry model, key genes in chromosomal regions controlling variation in these traits can be selected across different fruits and used to greatly reduce the time varieties are in development.