Abstract

The Scottish Crop Research Institute (SCRI) research on pests of high-value Rubus crops aims to maximize fruit quality while minimizing pesticide usage. Key pests that affect fruit quality and yield, and which are increasingly difficult to control with standard methods in the UK and Europe, include the raspberry beetle (Byturus tomentosus), large raspberry aphid (Amphorophora idaei) and raspberry cane midge (Resseliella theobaldi). SCRI and collaborating Swiss scientists have developed white sticky traps, enhanced with specific flower volatile attractants for raspberry beetle, which affects fruit quality, even at low-density. These traps are now being tested on commercial farms in the UK to optimize spatial arrangement, volatile release rates and trap design. The large raspberry aphid is an important virus vector in Europe. These decrease fruit quality, yield and plantation life. Several aphid resistance genes have been bred into SCRI and HRI-EM cultivars over the last 40 years. Due to increasing selection pressure, resistance-breaking aphid biotypes have overcome all single resistance genes, but multigenic, partial resistance remains durable. New sources of genetic resistance to pests are being investigated, aided by molecular marker technology. Optimal strategies for using pest-resistant cultivars in Integrated Pest Management (IPM; particularly synergism with natural enemies) are being investigated and modelled on software developed under DEFRA funding at SCRI. Raspberry cane midge control requires accurate timing of sprays against first generation midges. A computer-based prediction model, which was developed at SCRI and ADAS, is available throughout UK, and has been modified during the EU 'RACER' project for use in Italy and Switzerland. These components for IPM in Rubus are designed to satisfy EU legislation on pesticide reductions and meet the needs of growers, consumers and supermarkets while still maintaining high fruit quality. The next step is to put them together into grower-friendly IPM or organic packages and test them in different UK and European soft fruit production areas and systems (field and protected cultivation).