The effect of various techniques of planting material production and cultivation practices on the pathogenesis of apple proliferation phytoplasma in infected apple trees (Malus domestica Borkh.)

With the use of molecular (PCR, RFLP), and immunoserological (ELISA and immunofluorescence) methods for phytoplasma detection we will analyse the progress of the pathogenesis of experimental apple proliferation phytoplasma infections of apples grown in greenhouses and screen houses for several years. The scope of AP phytoplasma transmission with various grafting techniques and during various periods of the growth season will be investigated. Reliability and sensitivity comparisons of the most important analytical methods for confirming phytoplasma infections will be conducted on propagation material and on young trees. The effect of the intensity of fertilisation with mineral fertilisers and the effects of various pruning techniques on the expression of disease symptoms and on the yield from infected apples will be studied. The possibility of phytoplasma transmission from infected to uninfected apple trees through the root system will be assessed in greenhouse conditions.