EN
A field experiment was carried out in 2006–2008, in the Department of Agronomy, University of Life Sciences in Poznań, on the fields of Didactic and Experimental Farm Swadzim. The object of studies was the effect of magnesium dose (applied to the soil or to the leaves) on the occurrence of diseases in maize grown for grain with the use of the hybrid stay-green type LG 2244. The extent of maize plant infestation by Ustilago maydis and the fungi of Fusarium genus was significantly determined by weather conditions dominating in the period of studies. Application of magnesium, independent of the dose and the method applied, limited considerably the infestation of maize by U. maydis and Fusarium spp. diseases in the period of unfavourable weather course during maize vegetation.