A study into the sanitary state of roots and culm base of spring wheat was carried out in 2000–2002 at the Production and Experimental Station in Bałcyny near Ostróda. Experimental wheat was cultivated after spring cross plants such as spring barley (Brassica napus ssp. oleiferus Metz.), chinese mustard (Brassica juncea L.), white mustard (Sinapis alba L), oileiferous radish (Raphanus sativus var. oleiferus L.), false flax (Camelina sativa L.), spanish colewort (Crambe abbysinica Hoechst.) and after oat (Avena sativa L.) as the control. The spring wheat Torka cultivar was sown after ploughed stubble, ploughed stubble with straw and on stubble with straw and 30 kg nitrogen per ha. The greatest spring wheat root infections were observed in 2002. The culm base was most intensely infected with fusarium wilt (Fusarium sp.). The remaining root-rot diseases occurred every year but with different intensity. False flax and chinese mustard were the best predecessors for spring wheat. Only acute eyespot blotch occurred in lower intensity after colewort and oat. However, weather conditions had the major effect on the occurrence of root and culm base diseases in the experimental years. The method of utilisation of after-harvest residues did not have a clear effect on the intensity of infection of the roots and culm base of spring wheat.