The use of inorganic compounds to control apple scab in integrated fruit production

Inorganic fungicides such as sulphur, lime sulphur and copper are used for apple diseases control since long time, but recently they became the backbone of disease control in organic farming. Taking advantage of the experience acquired in the organic apple production, innovative formulations of these active ingredients, such as Thiopron, Poltiglia Disperss, as well as traditional ones like Polisenio, could be used more than at present, even in integrated production. This approach will contribute to overcome present and probable future restrictions on the use of synthetic fungicides. In a field experiment conducted in Trentino region (Italy) the efficacy and phytotoxicity of these inorganic fungicides was evaluated. Results show that these products can be efficiently used to control apple scab infection. Lime sulphur is particular effective when applied on wet vegetation within 300 degree hours from the beginning of the infection. No phytotoxic effect was detected on fruits. A control strategy that integrates these inorganic fungicides with synthetic active ingredients is possible and it will permit to reduce the dependence as well as the resistance selection pressure of synthetic fungicides.