Conditions for establishing fungicide anti-resistant strategy for the control of Venturia inaequalis (Cooke, Winter)

Apple scab (Venturia inaequalis Cooke, Winter) presents a major problem in apple production. The necessity to ensure high yields and fruit quality requires the application of fungicides. However, the long term use of systemic fungicides, particularly the once with the same mode of action (MoA), has led to the emergence of reduced susceptibility or resistance of V. inaequalis to certain active ingredients. Changes in sensitivity are manifested as a decrease of preparations efficiency, which results in increased number of treatments, thus the increase of fungicide amount of per surface unit. Fungicide Resistance Action Committee - FRAC has set internationally recognized principles for fungicide resistance management that can be implemented if a wide range of fungicides, with different MoA, exists. In the Republic of Serbia, there are 63 fungicides registered for the control of apple scab, based on 33 active ingredients, divided into five groups according to MoA, disregarding products containing two active substances. Regarding above mentioned principles, the basic conditions for establishing fungicide anti-resistant strategy for the control of V. inaequalis in our country exist.