An integrated control of the tortricid complex (Tortricidae) in Belgian pome fruit orchards

By far the most important tortrix moths in Belgian pome fruit culture are the codling moth, Cydia pomonella (L.) and the summer fruit tortrix moth, Adoxophyes orana (F.v.R.). The onset of integrated pest management (IPM) in pome fruit orchards around 10 years ago, was only possible because of the availability of selective insecticides against these lepidopteran pests. Diflubenzuron, used for the control of C. pomonella, and fenoxycarb, used for the control of A. orana, are harmless in field conditions towards the key beneficials used in IPM i.e. the predatory mites in apple culture and predatory bugs in pear culture. Since the beginning of IPM in pome fruit culture, very little has changed with regard to the control of these important pests. Due to the high natural pressure, yearly treatments with these compounds are done in most of the orchards. Warm summers often cause prolonged flights or additional generations, making multiple treatments necessary. Moreover, diflubenzuron or fenoxycarb are/were sometimes used for the control of other pests like leaf miners, winter moth, pear sucker. The lack of new selective compounds blocked every possibility for an adequate anti-resistance strategy. Besides, due to the use of these stage specific insecticides that are focused on the control of the major lepidopteran pest species, other tortricid moths, having a (slightly) different development remain present. After years of practising IPM, the numbers of these other moths i.e. Archips podana (Scopoli) and Spilonota ocellana (Denis & Schiffermuller) may increase considerably. Because of the recent registration of tebufenozide, flufenoxuron and granulosis virus in Belgium, these new insecticides were implemented in the current strategies for the control of C. pomonella and A. orana. The integrated management of the leafroller complex has become more important than the control of the single pest species. Different schemes, which have to be alternated, are proposed to avoid the formation of resistance and to maximalise the results, taking the orchard specific leafroller complex into account.