Increasing nitrogen doses were applied from 1975 to 1977 on Burley S51 at 2 locations with 8 procedures : I : basic organic fertilization; II : I + 1400 Kg/ha tobacco fertilizer 112 N + 84 P + 270 K; III : II + 50 N Nitrateform; IV : same as III NH4 form; V : as III but with 100 N; VI : as IV but with 100 N; VII : as III but usual fertilizers; VIII : as V but 1/2 nitrate. Yield and price were reported and quality characteristics as filling power, combustibility, total alkaloids and total-N were analyzed. Procedure V was found the best for yield and fr/ha. The influence of nitrogen on quality was undetectable; only total N was correlated with fertilization. The climatic conditions had a dominant influence on yield and quality (26762 points against 89 for the fertilization). (Nitrogen )