Különböző szisztémikus herbicidek fehér fagyöngy (Viscum album) elleni hatékonyságának, illetve a fagyöngy hiperparazita kórokozójára gyakorolt antifungisztatikus hatásának vizsgálata
There are more than 3000 ha in Hungary infected by European mistletoe (Viscum album L.), which have currently raised. The only way to control this hemiparasite is to cut down the infected branches, while other effective control methods are unknown. Our research focused on the efficiency of herbicide control methods against V. album. We tested three herbicide agents and combinations in three concentrations during our study (glyphosate isopropylamine salt, 2,4-dichlorophenoxyacetic acid, methsulphuron-methil). After the pesticide treatments the phototoxic effects were studied on mistletoe shrubs and on the host trees (Acer campestre L.) too. The most efficient agent was 2,4-dichlorophenoxyacetic acid, which caused the whole necrosis of mistletoe shrubs even in the lowest concentration, but low chlorosis, rarification of foliage and drying of twigs were detected on the host trees. Phaeobotriosphaeria visci, which seems suitable for biological control, appeared 3–6 months after the application of 2,4-D on the necrotic mistletoe shrubs. Therefore the effect of 2,4-D and glyphosate on the mycelial growth were examined under in vitro laboratory conditions. Even the lowest herbicide concentration caused significantly lower mycelial growth; besides higher concentrations no mycelial growth was detected. An incidental combined herbicide and spore suspension treatment is not possible, due to the antifungal effects of these pesticides.Peer reviewe