IMPACT OF LONG-TERM FERTILIZATION ON YIELD IN WHEAT GROWN ON SOIL TYPE VERTISOL

Experiments were carried out at stationary in Kragujevac, in Serbia, during the three growing seasons.The primary aim of the research was perceiving of the influence of long-term usage of the same amounts and rates of nitrogen, phosphorus and potassium on the yield and grain quality of winter wheat variety "Kruna".Uptake NPK uptake by wheat ranged from 120 kg ha -1 nitrogen, from 60 to 100 kg ha -1 phosphorus and 60 kg ha -1 potassium, respectively, depending on treatments type.The grain yield of the wheat was significantly lower in control (treatment without fertilizer).The three-year grain yield of winter wheat was the highest in the NP 1 K and NP 2 K (4.367 and 4.531 t ha -1 ) treatments.In terms of investigated traits, particularly grain yield and test weight fertilizer expressed more efficiency in the 2014/2015.Variance analysis showed statistically very significant differences for grain yield, 1.000-grain weight and test weight between the vegetation seasons and very significant differences for grain yield and 1000-grain weight between the variants of fertilization.Variance analysis showed very significant differences for 1000-grain weight between the interaction of the vegetation seasons and variants of fertilization.It could be concluded that the grain yield in all treatments in the 2014/2015 growing season was significantly greater than in the other examined years, mostly as the result of highly favorable weather conditions at major stages of plant development wheat.