Abstract:
Calcareous soil is dominant type in the Middle East region. This soil is known for its scarcity in available minerals P, Fe, and Zn. Field (on cucumber) and greenhouse (on corn) experiments were conducted to compare the efficiency of phosphoric acid (H3PO4) and triple superphosphate (TSP) as two sources of phosphorous fertilizer on calcareous soils. Seven different levels of P2O5 were tested in the field: T0 (control), T1 (TSP 50 kg-Ha), T2 (TSP 150 kg kg-Ha), T3 (TSP 25 kg-Ha + H3PO4 25 kg-Ha), T4 (TSP 75 kg-Ha 5+ H3PO4 75 kg-Ha), T5 (H3PO4 50 kg-Ha), and T6 (H3PO4 150 kg-Ha). While ten different levels of P2O5 were conducted at the greenhouse: T0 (control), T1 (TSP 50 kg-Ha), T2 (TSP 75 kg kg-Ha), T3 (TSP 150 kg kg-Ha), T4 (TSP 25 kg-Ha + H3PO4 25 kg-Ha), T5 (TSP 37.5 kg kg-Ha + H3PO4 37.5 kg kg-Ha), T6 (TSP 75 kg-Ha + H3PO4 75 kg-Ha), T7 (H3PO4 50 kg-Ha), T8 (H3PO4 75 kg kg-Ha), and T9 (H3PO4 150 kg-Ha). Results showed a significant difference in yield of cucumber between the control and all other treatments except T1, where T6 were the highest one with 4251.665 g-m2. The results also indicated a significant increase in the height of corn between treatments fertilized with phosphoric acid and the control. The dry weight of corn was significantly different between (T5, T6, T7, T8, and T9) and the control. The phosphorous and magnesium content of corn and cucumber leaves increase significantly when phosphoric acid was used as a source of P in the soil. However, Ca content of cucumber was significantly higher when the source of P was phosphoric acid. The results of both experiments showed that cucumber yield, corn growth, concentrations of P and Mg in both plant tissues, and Ca content of cucumber leaves responded positively and at significant levels to H3PO4 application as a single P source or in combination with TSP. This indicates that H3PO4 is a more efficient source for P in calcareous soils and its usage led to significantly improve the availability of P, Ca and Mg in soils, which led to a higher uptake o
Description:
Thesis (M.S.)-- American University of Beirut, Department of Agricultural Sciences, 2013.
Advisor : Dr. Isam Bashour, Professor, Agricultural Sciences ; Members of Committee : Dr. Nadim Farajallah, Professor, Agricultural Sciences ; Dr. Shady Hamadeh, Professor, Animal and Veterinary Sciences.
Includes bibliographical references (leaves 92-97)