Possibility of parasite (Marssonina brunnea (Ell. & Ev) P. Magnus and Melampsora spp) control on poplar foliage with some fungicides

The aim of this study was to test the protection of the clone Populus deltoides cl. S-6-36, with several fungicides, against the loss of height and diameter increment. The idea was to protect the leaf immediately from the beginning of vegetation growth against the attack pathogens. By the planed treatments, the foliage would be protected against the fungal attack during the first two to three months of vegetation growth, which would presumably contribute to avoid the significant decrease of height and diameter increments. The most efficient fungicide during the two-year research, both in the control of the fungus Marssonina brunnea, and in the control of Melampsora spp., was Bakarni kreč 50 (cupric oxychloride). This was concluded based on the lowest average number of formed acervuli, i. e. uredosori per cm2 of leaf area. A significant decrease of poplar tree increment occurs if the intensity of parasite attack on the foliage is high and if the attacks are repeated several years successively. Under the moderate attack of these pathogens (Marssonina brunnea and Melampsora spp) there is no significant loss of height and diameter increments