Field experiment was undertaken in Al-Ishaki Experiment Station (60 Km .north of Baghdad) during the summer season of 2005 and 2006 to study the effect of foliar fertilization of soybean (Lee-74) by 0.015% of each Fe,Zn and Mn (as sulfates) applied in single and in all possible combinations of these three elements on soybean seed yield and its components.
The results showed that foliar fertilization of soybean grown in calcareous soil by Fe,Zn and Mn in single and in all possible combination among these elements had significantly increased number of buds/plant ,weight of 100seed(gm), seed yield(gm)/plant, the seed yield Kg/ha. and had insignificant effect on seed number/bud in both seasons. It was noticed clearly that, the treatments involved Zn applied in single or in combination with Fe or Mn or both of them had the most effect in increasing the seed yield and its components in both seasons. The percents increases in seed yield of soybean by foliar application of Zn, Zn+Fe, Zn+Mn and Zn+Fe+Mn were 14.8%, 16.0%, 15.6% and 22.2% in season of 2005 and 13.2%, 15.6%, 20.3% and 25.4% for season of 2006 respectively. The nutrient productivity of applied single Fe,Zn and Mn were 0.94 , 1.44 and 0.70 Kg. seed/g nutrient for 2005 season and 0.85, 1.51 and 0.77 Kg seed /g nutrient for 2006 season respectively.