An investigation has been organized to study the effect of wheat seed inoculation (the cultivars Renesansa and Zlatka) with Azotobacter chroococcum, strain 86 (2-5x CFU 10(8) ml(-1)). Experiments were conducted under field conditions, on a chernozem soil. The effectiveness of inoculation on wheat seed quality (germination energy and percentage), yield and 1000-seed weight was shown to depend on the amount of applied urea (50, 100 and 200 kg ha(-1) and nonfertilized control) and wheat cultivar. A. chroococcum treatment, depending on variety and fertilizer treatment, increased the energy of germination by 1 to 9% and seed viability by 2 to 8%. Negative effects on seed germination energy and percentage were found in the case of the cultivar Zlatka, in the variant with 100 kg urea ha(-1). The largest increase in 1000-seed weight was obtained in the case of the cultivar Renesansa, in the variant without N application (16%). A. chroococcum inoculation increased the seed yield of both cultivars in the variant without urea application and with 50 kg ha(-1) of urea. The highest yield increase (74%) was registered in the case of the cultivar Zlatka when inoculated and treated with 50 kg ha(-1) of urea. All effects, except the yield, were low in the case of the cultivar Zlatka