Response of faba bean (Vicia faba, L.) variety Giza 184 to foliar application of copper and molybdenum was studied as possible factors to improve its yield and quality under phosphorus fertilization levels. Two field experiments were carried out at Sakha Agricultural Research Station Farm, Kafr El-Sheikh Governorate, during the two successive winter seasons of 2003/2004 and 2004/2005. Split plot design with four replicates was used. The main plots were assigned to three phosphorus application levels of 0(P0), 15 (P1) and 30 (P2) kg P2O5 fed-1 as superphosphate 15.5% P2O5. The sub plots were allotted for seven micronutrients foliar spray treatments of 0, 50 ppm copper (Cu1), 100 ppm copper (Cu2), 30 ppm molybdenum (Mo1), 60 ppm molybdenum (Mo2), Cu1 + Mo1 and Cu2 + Mo2. The results can be summarized as follows:
The effect of microelements application on seeds, straw and biological yields were highly significant. The highest mean values were recorded with Cu2 spraying, while the lowest values were obtained with P fertilizer only. The interaction between P levels and microelements spraying high significantly affected faba bean seed and straw, yields were obtained with P0Cu2 treatments. Phosphorus treatments affected the response of copper treatment, the least effect was under P2 treatment. The sequence effect of P treatments only can be arranged as follows: P1 > P0 > P2 in both seasons. Phosphorus heavy additions adversely affected faba bean yield. Increasing P fertilizers from 15 to 30 kg P2O5 fed-1 led to decrease the net return of faba bean compared to the control. The highest net return values of 825, 5 and 748 L.E., fed-1 were obtained under P0 Cu2 treatment in the first and second seasons, respectively. Increasing P fertilizer led to decrease the net return from faba bean treated with the copper fertilizer. The treatment of Cu2 had the highest nitrogen and protein contents in both seasons. Available N and P in the soil increased with increasing P fertilizer level.