A pot experiments were performed at the Faculty of Agriculture, Minufiya University, Shibin El-Kom to investigate the effect of different sources and rates, of P, Zn and Fe as well as organic manure on corn plants grown in both alluvial and calcareous soils. Two surface soil samples (0 – 30 cm) were collected from two locations. A) alluvial soil from Experimental Farm of the Faculty of Agriculture, Minufiya University, Shibin El-Kom. B) calcareous soil from Nubaria farm, Beheria Governorate. Each polyethylene pot (15 cm diameter) was filled with 2 kg soils and planted with five grains of corn plant (Zea mays L.). After 14 days from planting the plants thinned to three plants per pot. The pots were irrigated to keep soil moisture at approximately 60% of the water holding capacity. The Farmyard manure (FYM) was added at (0, 1 and 2%) P- was added at (0, 15 and 30 ppm, P2O5) of superphosphate and Triplephosphate. The Farmyard manure and phosphatic fertilizers were added before planting. The third part was treated with zinc at rates of 0, 10 and 20 ppm as zinc sulphate and Zn-EDTA. The fourth part was treated with iron at reates of 0, 15 and 30 ppm as iron sulphate and Fe-EDTA from planting the plants were harvested and dried at 70°C weighted, ground and digested for chemical analysis.
The application of FYM at rates of 1 and 2% to the both alluvial and calcareous soils caused a significant increase on dry matter yield of corn plants. The highest values of dry matter yield was found in alluvial soil. The additions of FYM to both soils increased the Zn and Fe uptake by corn plants and availability of DTPA extrable Zn and Fe. The application of phosphatic fertilizers increased the dry matter yield of corn plants grown in both alluvial and calcareous soils, the dry matter yield of corn plants with triplephosphite applicat on was higher then those with super phosphate in alluvial soil, while the reverse was true in calcareous soil. The Zn and Fe uptake by corn plants were obviously higher on alluvial soil than those on calcareous one with P application. The application of P fertilizers decreased the DTPA-extractable Zn and Fe soils in used. The highest dry matter yield values of corn plants were obtained by Zn addition as Zn-EDTA treatment than ZnSO4 in both alluvial and calcareous soils. The values of micronutrients (Zn and Fe) uptake by corn plants with Zn-EDTA were higher than ZnSO4 in both alluvial and calcareous soil. The corn plants were more responsed by Zn-EDTA in calcareous soils. Application of Zn fertilizers increased the available Zn in both alluvial and calcareous soil. Addition of Zn fertilizers increased the DTPA-extractable Zn. While decreased the DTPA extractable Fe and Cu. The addition of Zn-EDTA recorded higher amounts of available micro elements than those obtained by using ZnSO4 in both alluvial and calcareous soil. The application of Fe at rates of 15 and 30 ppm in both sources resulted a significant increases in the dry matter yield of corn plants grown in both alluvial and calcareous soils. The Fe-EDTA gave higher dry matter yield as compared with FeSO4. The micronutrients uptake was markedly increased with Fe-EDTA addition as compared with FeSO4 in both soils. Addition of Fe increased the DTPA extractable Fe in used soils, while decreased the DTPA extractable Zn in alluvial soil.