The endemic presence of the blue mold (Peronospora tabacina Adam) in Cuba and the appearance of strains of the fungus resistant to the main fungicide used for its control, all this has obey to develop the breeding program in order new varieties resistant to this disease, having the same organoleptic quality that characterized the Cuban tobacco in the world. The first step to achieve up to this objective, was a crossing between the ‘Pelo de Oro’ traditional variety and the Polish ‘Rx T’ variety, having the resistant genes for blue mold inherirant from Nicotiana rustica. The agricultural technique was utilized in irrigation conditions. The same genealogical modified selection system was used, that includes a comparative test between the best lines of F 6 y F7 generations. In this test a four repetitions design at random was used. From the eight evaluated lines, three of them have the high yield concerning weight and class, and also ‘L-2-1’line has good combustibility.
Key words: Breeding, genetic resistant, blue mold, genes.