Influence of Micronutrient Fertilizer on Soybean Nutrient Composition

In order to study the effects of micronutrient fertilizers on nutrient composition of soybean, two set of experiments (pot and field) were done at the Islamic Azad University of Kermanshah province, Iran in 2010. The experimental design was a 3×3×3 factorial experiment based on Randomized Complete Block with three replicates. In the pot experiment, treatments included Zinc (0, 4, and 8 mg Zn kg^-1 as ZnSO₄.7H₂o), iron (0, 4, and 8 mg Fe kg^-1 as FeSO₄), and manganese (0, 15, and 30 mg Mn kg^-1 as MnSO₄.4H₂O). Treatments in field experiment consisted Zn (0, 20 and 40 kg Zn ha^-1), Fe (0, 25 and 50 kg Fe ha^-1) and Mn (0, 20 and 40 kg Zn ha^-1) from source of ZnSO₄, FeSO₄ and MnSO₄ , respectively. The results were shown that Zinc application had significant effects on Zn, Fe concentration in ischolar_mains (P-1. A similar trend was observed with manganese application (30 mgkg^-1 soil treatments). In the field experiment, Zinc concentrated more in seed compared to other parts of plant. While, iron application resulted [Fe] more its concentration in leaf but its further increase (> 25kg.ha^-1Fe) resulted negative effects; however, the application of Mn brought down the negative effect. Mn up to 20 kg.ha^-1 had little effect on iron absorption, but its further increase reduced concentration of iron in stem, pod and grain. This study also shows that high soil concentration of manganese and iron had negative effects on zinc absorption. There was a significant and negative correlation between manganese and iron concentration in seed (r=0.558) and Mn and Fe concentration in leaf (r= 0.397).