The efficiency of nitrogen fertilizer on the dry matter yield of tall fescue and festulolium grown as feedstock for combustion
¹Latvia University of Life Sciences and Technologies, Liela iela 2, LV-3001 Jelgava, Latvia
²Institute of Agricultural Resources and Economics, Struktoru iela 15, LV-2006 Riga, Latvia
Grass biomass grows during one vegetation season and can be cultivated and consumed at the place of breeding. Grass biomass can be used not only in traditional feed, but, recently, also for energy production (biogas, solid fuels). The most important economic indicator for any crop is its productivity. The study found that it is important to use nitrogen fertilizer to increase the productivity of tall fescue and festulolium. A significant increase (p < 0.05) in the yield of tall fescue was observed starting from the nitrogen norm of 60 kg ha-1 N. Further increase in nitrogen fertilizer norm provides a significant increase in dry mater yield of tall fescue (reaching 8.64 t ha-1) and festulolium (reaching 8.11 t ha-1) at 180 kg ha-1 N. The analysis of linear regression coefficients of polynomials showed that the highest nitrogen efficiency in the first year of the use of tall fescue was achieved at the norm of 180 kg ha-1 N, but for festulolium – at the norm of 120 kg ha-1 N. In the following years of tall fescue use, the highest efficiency of nitrogen norms differed: in the 2nd and 4th year of use – at 60 kg ha-1 N, in the 3rd year of use – at 30 kg ha-1 N, and in the 5th year of use – at 120 kg ha-1 N. In contrast, for festulolium, in the 2nd year of use, the highest nitrogen efficiency was reached at the norm of 30 kg ha-1 N, and in the 3rd–5th year of use – at the norm of 60 kg ha-1 N.