THE ANALYSIS OF THE REGRESSION COEFFICIENTS BETWEEN THE QUANTITY OF NITROGEN ADMINISTERED AND THE SEED YIELD DEPENDING ON POTASSIUM SOIL FERTILIZER BASE ON THE ARCHITECT RAPESEED HYBRID CROPED IN THE S-E AREA OF ROMANIA

Abstract

In the south-eastern area of Romania, the Arhitect rapeseed hybrid was tested in trail fields, in order to determine its biological potential in the ecological conditions specific to this area. In this research, the influence of potassium and nitrogen fertilization on seed yield was analyzed and also the analysis of the regression coefficients between the amount of nitrogen administered and seed yield according to the potassium soil fertilizer base was determined. Thus, regardless of the potash soil reserve, nitrogen ensures an increase in seed yield at least in this rapeseed cultivar, with the most important increases in yield being recorded under conditions of the most abundant fertilization. From an economic point of view, the profit calculated from the difference in yield due to the application of fertilizers, was obtained only in the variants where 150 kg N s.a./ha was administered in conditions of abundance in potassium. In other words, the administration of potassium can bring an increase in profit, only in conditions of abundant fertilization with nitrogen, otherwise the application of potassium is not economically justified.