Spring triticale yield formation and nitrogen use efficiency as affected by nitrogen rate and its splitting

Little information exists on the pattern of nitrogen (N) uptake, remobilization and N use efficacy in spring triticale. The study was aimed to determine the effect of N rates and application regimes on the yield, yield components, as well as to ascertain optimal N fertilization regime for spring triticale. The study was based on the experiment carried out at the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry in Central Lithuania on an Endocalcari-Endohypogleyic Cambisol (CMg-n-w-can) during the period 2008-2011. The data were analysed using ANOVA method. Nitrogen was applied as basic fertilization (N60-180) shortly before sowing, and N-90, N-150 rates were split in two or three applications. Grain yield, yield components (ears m(-2), grains earl, productivity g ear(-1), and thousand grain weight), grain protein content and nitrogen use efficiency (NUE) were investigated. The analysis of variance of the data averaged over the four experimental years showed that experimental year significantly (P <= 0.01, P <= 0.05) influenced all the tested parameters on both basic fertilization backgrounds and N splitting treatments. The influence of N rate on the investigated parameters was significant (P <= 0.01, P <= 0.05) on basic fertilization backgrounds almost in all the cases; however, the influence of N splitting regime on the yield and yield components was insignificant. N splitting significantly (P <= 0.01) influenced protein content and all indices of NUB. Fertilization increased the grain yield by 35.7%, compared with the unfertilized control treatment. The N90-120 rate was found to be economically and ecologically optimal for spring triticale. It resulted in the highest (4.81-4.92 Mg ha(-1)) grain yield.