Carrot psyllid – Swedish experience in practical farming and trials

Abstract: The carrot psyllid, Trioza apicalis, is a pest of carrots in northern and central Europe but it has so far mainly been a problem in Norway, Finland and Sweden. The psyllid is a major pest in Swedish carrot production and reduces both yield and quality of the carrots.The new legislation on Integrated Pest Management is introduced at the same time as the problems with the carrot psyllid are increasing and the possibilities to control the psyllid chemically are reduced. Hence there is a need to initiate research into new means of both chemical and alternative control. Chemical control in practical farming is mainly based on pyrethroids (Karate 2.5 WG and Mavrik 2F). Because the number of applications with these products are limited, seed treatment with thiamethoxam (Cruiser) and spraying with different systemic insecticides have been tested. For organic production and IPM concepts parrafin oil and plant extracts are included in one trial. Different substances are tested alone, in strategies and in IPM concepts.Strategies that alternate pyrethroids and systemic insecticide show very good results on leaf curling, leaf discoloration and yield.