Ekonomska isplativost primene različitih količina azota u proizvodnji hibrida kukuruza različitih FAO grupa zrenja na zemljištu tipa černozem

The aim of this study is to determine the optimum quantity of nitrogen applied in corn production at which maximum profit is achieved. Optimal nitrogen application is important for two main reasons: first for achieving maximum profitability in the production of maize and other is to avoid environmental pollution as the nitrogen is one of the main polluters. In the three-year period (2005 - 2007) were performed research on the effects of nitrogen quantity (control - without fertilization, PKNfon, PKN60, PKN120 and PKN180) and hybrids of different vegetation length (ZPSC 434 ZPSC ZPSC 578 and 677) on yield and profitability. Increasing application of nitrogen tended to raise grain yield by 9.9 - 13.5%. The lowest average corn grain yield (9.49 t ha-1) was registered with the hybrid ZP 434. It was somewhat higher (9.75 t ha-1) with the hybrid ZP 578 and the highest corn grain yield (10.03 t ha-1) with ZP 677. Study shows that highest yield is not always most profitable. In production year with good water supply (2005) highest profit is achieved with moderate use of nitrogen (60 kg ha-1). In draught production years (2006 and 2007) highest profit was achieved with application of 60 to 120 kg ha-1.Cilj rada je utvrđivanje optimalne količine primene azota u gajenju kukuruza pri kojoj se ostvaruje maksimalni prihod. Optimalna aplikacija azota je važna iz dva razloga: prvo za postizanje maksimalne profitabilnosti u proizvodnji kukuruza i drugih je da se izbegne zagađenje životne sredine s obzirom da je azot je jedan od glavnih zagađivača. Istraživanja su sprovedena u periodu od tri godine (2005 - 2007) o efektima količine primenjenog azota (kontrola - bez đubrenja, PKNfon, PKN60, PKN120 i PKN180) i hibrida različite dužine vegetacije (ZPSC 434 ZPSC ZPSC 578 i 677) na prinos i profitabilnost proizvodnje. Povećanje primena azota ima tendenciju da podigne prinos od 9,9 - 13,5%. Najniža prosečan prinos zrna kukuruza (9,49 t ha-1) je registrovan kod hibrida ZP 434. Prinos je bio nešto veći (9,75 t ha-1) kod hibrida ZP 578 i najviši prinos zrna (10,03 t ha-1) sa ZP 677. Studija pokazuje da najveći prinos nije uvek najprofitabilnija. U proizvodnoj godini sa dobrim vodnim režimom (2005) najveći profit je ostvaren sa umerenom upotrebom azota (60 kg ha-1). U sušnim proizvodnim godinama (2006 i 2007) najviši profit ostvaren je sa primenom 60 do 120 kg ha-1