Selekcija i Semenarstvo (Jan 2005)
Effects of the time of application and the form of nitrogen on two maize inbred lines seed yield
Abstract
The study was carried out in the experimental filed of the Maize Research Institute, Zemun Polje, on calcareous chernozem in the period 2001-2003. The traits of two maize inbred lines (L1-FAO 400 and L2-FAO 600) were observed in dependence on the time of the nitrogen application (No-control without fertilizing; Nautumn - 60 kg P2O5 ha-1 and 60 kg K2O ha-1 applied in autumn (const) + 100 kg N ha-1 (applied in autumn); Nspring - PK (const) + 100 kg N ha-1 (applied in spring); N1/2 - PK (const) + 100 kg N ha-1 (half of which was applied in autumn and the other half in spring); N1/2-PK (const) 100 kg N ha-1 (1/3 of which was applied in autumn, 1/3 in spring and 1/3 through soil dressing); Nmin - PK (const) + fertilizing in spring on the basis of the Nmin method, and forms of applied nitrogen: Urea (amide form) KAN (ammonium-nitrate form) and (NH4)2SO4 (ammonium form). The highest average yield was obtained by the use of Nmin method (3,486 kg ha-1), as well as, 100 kg N ha-1 applied in sprig (Nspring) (3,337 kg ha-1), 100 kg N ha-1 applied in autumn and spring (N1/2) (3,020 kgha-1) and 100 kg N ha-1 applied in autumn, spring and soil dressing (N1/3) (3,005 kg ha-1) in the ammonium-nitrate form (KAN). The highest average seed yield of observed maize inbred lines (3,264 kg ha-1) was obtained by the application of ammonium-sulphate in the primary tillage (Nautumn). The use of the Nmin method (N ranging from 17 to 35 kg ha-1, in dependence on the soil mineral nitrogen content), especially in years with lower precipitation sums resulted in the highest increase in seed yield (39.2%) of observed maize inbred lines in relation to the control.
