AbstractThe incidence of vascular lesions caused by fungi associated with the infection of young canes by the raspberry cane midge (Resseliella theobaldi) was studied in plots of red raspberry cvs Glen Clova and Malling Jewel given a five-spray eradicant programme of benomyl alone, fenitrothion alone, or a combined programme with both chemicals applied to cover young canes during the prolonged oviposition period of the second generation of the pest. The proportion of canes with spreading stripe lesions associated with Leptosphaeria coniothyrium was reduced by benomyl, fenitrothion and by the combined programme in both cultivars in all three years that sprays were applied, compared with the unsprayed controls. The proportion of canes with lobate patch lesions caused by Fusarium and Phoma spp. was reduced by fenitrothion and the combined programme but the incidence was unaffected or even increased by the use of benomyl alone. Control of stripe lesions by the insecticide fenitrothion suggests that L. coniothyrium is involved in the midge blight disease complex in Scotland.