The wildfire ( Pseudomonas syringae p.v. tabaci ) is widely spread in Bulgaria. This disease causes severe injuries to tobacco plants. It kills the seedlings, reduces the yield and the quality of the cured leaves. Therefore, it is economically the most important bacterial disease of the tobacco crop in the country. The tobacco line WZ developed by Smeeton and Ternouth, which is resistant to Race 1 of the pathogen was examined under Bulgarian environmental conditions. The experimental data indicate that the line is resistant to Race 1 of the pathogen. The line WZ was crossed with tobacco cultivars of Oriental and Virginia types susceptible to wildfire. The inheritance of the resistance to wildfire was investigated in F₁ and F₂ hybrids. The data suggest that the resistance to Race 1 of Pseudomonas syringae p.v. tabaci in F₁ hybrids of line WZ with the susceptible cultivars and lines Rila 82, Rila 544, Rila 9, PMR Burley 21, Triumph, BAN 324, Virginia 276 and Line 81 is inherited dominantly. F₂ plant segregation in a ratio 3 resistant:1 susceptible was observed. This genetical analysis of the inheritance of the resistance to wildfire in F₂ indicates that it is controlled by a dominant gene. The results obtained here clearly suggest that line WZ may be efficiently used in tobacco breeding programmes under Bulgarian environment.