Engineering tolerance to Botrytis in soft fruit crops

Botrytis cinerea, Grey Mould disease, is a common necrotrophic fungal pathogen of soft fruit crops and causes huge economic losses each year. The pathogen prefers to infect damaged or senescing tissues, such as flowers and fruit, eventually leading to tissue death. Cultivated strawberry (Fragaria x ananassa) accessions appear to be universally susceptible, although variation of incidence and severity of grey mould has been reported. Resistance/tolerance has been reported in the wild progenitors Fragaria chiloensis and Fragaria virginiana. Several known fungal inhibitors are highly induced in resistant F. chiloensis accessions, but the mechanism of resistance is not understood. In raspberry, much less is known, although resistance to cane botrytis has been associated with Gene H, which controls cane pubescence.

NIAB EMR has a collection of wild strawberry material that can be screened for resistance/tolerance to grey mould. It also has wealth of genomic data on the cultivated strawberry and several wild accessions, which can be mined for presence of known components of tolerance to B. cinerea. At present, there are very few genomic resources publicly available for raspberry; this is hampering research on a range of traits including disease resistance.

The project will focus around the following questions: 1) What are the genetic components of Rosaceae-Botrytis interactions? 2) What can usefully be brought from wild species into cultivated strawberry and raspberry to protect against B. cinerea?

Project objectives:
1. Screen diverse strawberry and raspberry material, including wild relatives for tolerance/resistance to Botrytis fruit rot in controlled experiments.
2. Characterise the genetic pathways of the cultivated strawberry-B. cinerea and raspberry-B. cinerea through molecular analyses of the infection process.
3. Transform cultivated strawberry and raspberry (using CRISPR) with known pathogenesis-related proteins from wild strawberry and determine effects on Botrytis colonisation.

Outputs from this project will lead to a greater understanding of this economically important disease but will lead to improvements in breeding material, reducing losses from this devastating disease, as well as building up resources for strawberry and raspberry.