Phenology of brassica root flies (Delia radicum and D. floralis) in northern Europe

Abstract: Knowledge of the patterns of pest fly emergence is vital for development of robust forecasting models. In this study we have collected samples of cabbage root fly pupae from several countries, and studied the fly emergence patterns under controlled temperature conditions. Results showed a majority of early emerging flies in all cases, but general conclusions about the occurrence of early, intermediate and late emerging flies could not be drawn due to a limited number of samples in the emergence tests.