Organomineral fertilizer phosphorus availability in a calcareous soil

This MSc Thesis aimed to test the role of organomineral fertilizers, which have become widespread in recent years, on the phosphorus (P) use efficiency. For this purpose, an incubation test and a pot experiment were carried out to see the effect of P in organomineral fertilizer (OMF) prepared by mixing the mineral fertilizer (MF) source P with the organic fertilizer (OF) from the biogas plant on the availability of P in soil and on the nutrition of the wheat plant. In both experiments, increasing rates of OMF-P were applied to the same depth (6 cm below the surface) and compared with the triple super phosphate (TSP) fertilizer applied to the same area. In the incubation experiment, the soils were sampled twice, on the 45th and 90th days. Olsen P, an indicator of P availability in calcareous soils, was measured in homogenized soils. In the pot experiment, two samples were made during the tillering and maturation periods. During the tillering period, the whole plant was sampled, and at the maturity harvest, two separate samples were taken plant stubble and grain. Phosphorus, nitrogen (N), and potassium (K) concentrations were measured in plant samples. The content and uptake values per pot were calculated for each nutrient by multiplying these with dry weights. As a result of the incubation experiment, it was observed that the Olsen P contents of the soils treated with the OMF-P were higher at both sampling times than those with the MF-P. In line with this, both the P concentration in the shoots and the P uptake per pot were higher in the plants treated with the OMF-P in the plant samples of the tillering period. A similar trend was observed for P content in grains and total P uptake at maturity harvest. There were no definite results for N and K that the presence of organic fertilizers improved the N and K nutrition of the plants. In general, the P application increased N and K contents in the grain, and when total uptakes were considered, N uptake increased, but no effect on K was observed. However, there is still a need to compare the results with those obtained under field conditions.