Balanced Fertilization of Major Crops of Rainfed Area in Jordan

The objectives of this project were to: (a) determine the effect of balanced fertilization on the yield of major crops of the rain-fed area in Jordan and (b) to increase awareness and transfer the knowledge of the fertilizer best management practices. In this study, several trials were conducted in the southern part of Jordan (Karak governorate), in the central region (Amman-Madaba governorate) and in the northern region (Irbid governorate). These locations represent the different agroecological zones of Jordan. For this project in 2016, several field experiments on wheat were conducted at all locations. In the northern region, there were two additional field demonstrations on onion and olives. The following treatments were investigated: (T1) farmer fertilization practice (FFP) which represents the recommended rate by the Ministry of Agriculture, where diammonium phosphate (DAP) and urea fertilizers were applied before seeding at rates of 100 and 55 kg/ha, respectively; (T2) nitrogen, phosphorus, and potassium (NPK), representing the balanced fertilization, where DAP, urea and sulfate of potash (SOP) fertilizers were applied before seeding and at tillering (50% and 50%) at rates of 100, 55 and 60 kg/ha, respectively; and (T3) NPK+, representing the balanced fertilization for higher yield, where fertilizers were added in the same combination as in T2, but a 25% higher application rate. The target yield for treatments T1 and T2 was 2 t/ha, meanwhile, the target yield for the treatment T3 was 2.5 t wheat grain/ha. The area allocated for each treatment was 0.5 ha.

In southern Jordan, the grain yields for T1, T2, and T3 treatments were 1.8, 2.4, and 1.7 t/ha at one farm and 1.54, 1.46, and 1.48 t/ha at the second farm, respectively. In central Jordan, the wheat grain yield for the T1, T2, and T3, at one farm was 1.52, 1.40, and 1.79 t/ha, and 1.44, 1.07, and 1.42 t/ha at the second farm. In northern Jordan, where wheat was planted at one farm and onion at the second farm, the wheat grain yields for the T1, T2, and T3 were 1.28, 1.54, and 1.58, respectively. The dry onion yields were 16.6, 49.9, and 41.7 t/ha for the Texas variety and 21.1, 31.7, and 37.9 for the local Giza variety for the T1, T2, and T3, respectively. For the olive plantation, the highest fruit yield was obtained by the balanced NPK application (78.2 kg/tree) while the lowest fruit yield was with FFP (43.5 kg/tree).