THE EFFECT OF DIVIDED TOP-DRESSING APPLICATIONS OF DIFFERENT NITROGEN FERTILIZERS ON GRAIN YIELD AND QUALITY TRAITS IN BREAD WHEAT (Triticum aestivum L.)

This study was carried out to determine the effect of different divided top-dressing applications of different nitrogen fertilizers on grain yield and quality traits of four bread wheat varieties (Selimiye, Esperia, Gelibolu and Rumeli). The experiments were conducted in a randomized split-plot design with 3 replicates during the 2017 and 2018 growing seasons. In the experiment, varieties were allotted as main plots and top-dressing applications were allotted as subplots. Five different pure nitrogen (N) top-dressing applications were done in the form of urea and calcium ammonium nitrate (CAN) at the beginning of tillering, the end of tillering, the beginning of stem elongation and the end of stem elongation stages. In the study, changes in grain yield, thousand kernel weight, test weight, protein content, wet gluten content, gluten index, Zeleny sedimentation value and delayed sedimentation value were investigated. Gelibolu variety for grain yield, Rumeli and Esperia varieties for grain quality were prominent. The considering the ease of application for grain yield and quality, 2nd application (80 kg ha-1 pure N in the form of urea at the beginning of tillering, 40 kg ha-1 pure N in the form of urea at the beginning of stem elongation) can be proposed in the years when April and May rainfalls are sufficient, and 3rd application ( 40 kg ha-1 pure N in the form of urea at the beginning of tillering, 40 kg ha-1 pure N in the form of urea at the end of tillering, 40 kg ha-1 pure N in the form of CAN at the beginning of stem elongation) can be proposed in the years when April and May rainfalls are insufficient.