Dynamic release of ascospores of Venturia inaequalis and apple scab diseasecontrol strategy based on the Mills and RIMpro models in Girona (Catalonia-Spain)

Abstract: Apple scab is the most important disease on apple production in the North-East ofCatalonia, Spain. In the last 25 years the disease control has been based on fungicide spraysapplied according to the Mills model. From 2004 to present days some trials have been carriedout to validate the RIMpro model in the natural conditions of this geographic area. This papershow results from trials performed during two years comparing the number of ascosporesdischarged predicted by RIMpro forecast system and the ascospores trapped by Burkard sampler.Results obtained from field trials focused on the control of apple scab by using RIMpro and Millspredictive models for the primary infections control are also presented. High coincidencebetween real ascospores release periods and RIMpro predictions was observed, but in someperiods intensity level differed. The disease control was effective in both predictive modelsthough less infection warnings and less fungicide sprayings were needed in the RIMpro modelplots.