Two field experiments were carried out at Gemmeiza Agricultural Research Station, Gharbia Governorate during two seasons (2008 and 2009) to study the effect of four aminototal concentration (i.e without, 1g/L, 2g/L and 3g/L) under three N
(15, 30. and 45 Kg N/fad.) and their interaction on leaf chemical composition, yield and yield components of the Egyptian cotton cultivar, Giza 86. Results indicated that the differences between N rates for leaf N content, number of fruiting branches / plant, plant height, number of flowers and bolls / plant, earliness %, boll weight , seed cotton yield per plant and per fad. were significant in the two seasons, where, boll setting % and boll shedding % were significant in the first season only. Rate of N fertilizer 45 kg N/fad. Gave the highest values for leaf N content, number of fruiting branches per plant and plant height, where, 30 kg N/fad. Gave the highest values for leaf K content, number of flowers and bolls per plant , boll weight, seed cotton yield / plant and per fad., on the other hand, 15 kg N/fad gave the best values for earliness % in the both seasons. The differences between 45 kg N/fad and 30 kg N/fad. were insignificant for all studied traits in the both seasons. Foliar application of aminototal gave a significant effect on leaf N and K contents, number of fruiting branches per plant, plant height, number of flowers and bolls per plant, boll weight, seed cotton yield per plant and per fad. on the other hand, earliness %, boll setting and boll shedding % were insignificant in the two seasons. Foliar cotton plants with concentration of 3 or 2g/L from aminototal gave the highest values of most studied attributes. The differences between 2g and 3g/L aminototal were in significant of all studied traits.The interaction between N rates and aminototal concentration were significant for all studied traits except earliness % in the two seasons. Also, results show that, fertilization cotton plants with 30 kg N/fad. and sprayed with 2g/L aminototal increased the yield and yield components under experiment soil conditions.