Fertilizer is one of the basic inputs for agricultural production. In general, it is known that all kinds of plant nutrients are more or less in all agricultural soils. For this reason, the main skill in fertilization is to determine the type and amount of plant nutrients deficient in the soil and to ensure that fertilization is carried out in a timely and proper manner.

The amount of fertilizer to be given is affected by factors such as the cultivated plant, variety, soil fertility level, climatic factors (irrigation, rainfall) and the agricultural system applied.

Fertilization provides yield increase only when all these factors are taken into consideration and this increase is economical.

NPK fertilization to be applied according to the results of soil analysis and trace element applications, the deficiency of which is determined, are sufficient to obtain high yields from cereals.

Fertilization at the appropriate time and dose will lead to an increase in quality as well as yield. Especially in today's price policy where purchases are made according to the protein ratio, obtaining high protein products with high grains without spinning is closely related to nitrogen fertilization.

Phosphorus uptake rate is higher in the first development periods of plants. Phosphorus concentration of young plants is higher than that of older plants.

Since the phosphorus taken in the early stages of development can be sufficient throughout the entire development period, early phosphorus application is essential for high yield. In particular, early phosphorus intake is necessary for plants to form grass sheaths.

Wheat takes 75% of its total phosphorus requirement in the period when it realizes 25% of its total development.

Although phosphorus uptake by plants varies depending on soil pH, temperature, moisture, lime, clay minerals and organic matter content and soil aeration, the recommended amount of phosphorus for cereals varies between 7 kg/da in dry farming and 9-10 kg/da P205 in irrigated farming.

The needs of the plant should be met with compound or phosphorus fertilizers equivalent to these recommended amounts.

Nitrogen Fertilization

Wheat requires a certain level of available nitrogen to be present in the soil throughout the development period. It takes 45% of its total need from seedling period to emergence, 25% from emergence to the beginning of spike and 30% from spike to grain maturity.

The nitrogen needed by bread wheat during the growing season varies between 7-9 kg N/ha in dry and 18-21 kg N/ha in irrigated agriculture depending on factors such as soil organic matter, preceding crops, yield potential of the cultivated variety and nitrogen water balance. When this total nitrogen requirement is divided according to the different development periods of the plant, we can state the amount of nitrogen that should be kept in the soil under irrigated conditions as follows. Of the total nitrogen requirement, 8-10 kg should be given to the plant from sowing until the tillering period, 5-6 kg should be given from stem emergence until the pre-spike period and the remaining 5 kg should be given to the plant from the beginning of spike (sheath period) until the grain maturity period.

We can explain the fertilizer value of these figures over fertilizers with an example as follows; For example, let's assume that we sow with 20 kilograms of DAP fertilizer per decare. All of the phosphorus that the plant will need will be met and about 3.5 kg of total nitrogen will be given by planting. The first amount of nitrogen fertilizer to be given immediately after winter until the end of the tillering period; 11-14 kg per decare if it is urea fertilizer, 22-32 kg if it is ammonium sulphate fertilizer, and the second amount of nitrogen fertilizer to be given before spike emergence; If it is urea fertilizer, 11-13 kg per decare, if it is ammonium sulphate fertilizer, 25-30 kg per decare, if it is urea fertilizer, 11 kg per decare, if it is ammonium sulphate fertilizer, 25 kg per decare should be given from the beginning of spike (sheath period) to the grain maturity period. If these applications are made at the beginning of the specified plant development periods, the effectiveness of the fertilizer will be increased even more.

Especially during the flowering period, the third nitrogen fertilizer application mentioned above must be applied. Because the presence of high levels of useful nitrogen in the soil increases the nitrate content of the plants, which leads to an increase in the grain protein ratio. The increase in protein ratio increases the quality and glassiness of the grain.

There is no statistical difference between nitrogen fertilizers in terms of plant usefulness. The difference is in terms of washing, denitrification, effect on soil pH and usefulness of other elements.

In addition to nitrogen and phosphorus, trace elements, especially zinc, which cannot be taken up by the plant due to the high level of lime in the soil, and foliar potassium applications can be stated as important applications that increase both yield and quality.