The Effect of Different Fertilizer Applications on the SPAD Values of Wheat, Green Part Yield and N Concentration

Abstract

In recent years, the unconscious use of both pesticides and chemical fertilizers has led to the emergence of products that are of poor quality and threaten human health, as well as an increase in crop production. It seems that there is a need for studies on sustainable agriculture and different agricultural alternatives against these problems. It has been seen that the most common problem of plants under different agricultural practices is the way of nitrogen (N) use. It has been thought that the N dose and form of the fertilizer applied are important in the N use efficiency of the plant. For this purpose, the effect of N applications in increasing doses (0 (control), 100, 200, 400 and 800 mg N kg-1) and in different forms (mineral, organic) on growth, the SPAD value which is an expression of chlorophyll in shoot, shoot dry matter yield, shoot N concentration of wheat plant grown under greenhouse conditions was determined. According to the findings obtained in the experiment, it was determined that there were yield losses due to N deficiency, whereas N application prevented the mentioned yield losses. It has been determined that the N form applied on the yield increase rates resulting from nitrogen application can also be important. It was observed that the yield increase rates under mineral fertilizer applications varied between 58% and 87%, whereas organic fertilizer applications caused a partial decrease in the yield values. Different forms of N applications increased the shoot N concentration in contrast to the shoot dry matter yield of the plant. In these increases, it was determined that the N application dose was important, but the fertilizer form applied did not make a significant difference. When the results were evaluated in general, it has been seen that the most effective N application dose was 200 mg kg-1, and among the N forms, the most effective form in plant growth and N use efficiency was organic sourced fertilizer.