Abstract

The use of the desiccant dinoseb to manage excessive cane growth of raspberries and control cane pests and diseases was banned in the UK in 1988. The results are presented of a trial in Scotland to compare insecticide for the control of Resseliella theobaldi and the midge blight caused by this cecidomyiid, in plots treated with dinoseb or untreated. Midge populations and damage were greatly reduced with dinoseb, and insecticides were unnecessary to protect replacement canes. In plots untreated with dinoseb, 2 applications in June of fenitrothion at 525 or chlorpyrifos at 470 g a.i., both applied in 1100 litres of water per ha, controlled 1st-generation R. theobaldi and lesion development. Damage to 1st-flush canes was reduced to a leser extent by fenitrothion and by one of 2 treatments with γ-HCH [lindane]. Some alternative methods for controlling the cecidomyiid without pesticides are discussed.