Impact of phosphorus fertilization and growing season on maize grain yield

Abstract

Nedostatak fosfora je često jedan od limitirajućih faktora uspješne proizvodnje ratarskih kultura. Fosfatizacija je jedna od agromelioracijskih mjera kojom se u tlo unose veće količine fosfora i poboljšava plodnost tla. Cilj ovog istraživanja bio je utvrditi učinak vremenskih prilika i fosfatizacije tla na prinose zrna kukuruza na području općine Odžak (BiH, FBiH), tijekom 2011. i 2012. godine. Poljski pokus postavljen je na alkalnom tlu siromašnom pristupčnim fosforom u proljeće 2011. godine po slučajnom blok sustavu u četiri ponavljanja s pet tretmana: A) kontrola (osnovna gnojidba); B) A + 200 kg P2O5 ha-1; C) A + 400 kg P2O5 ha-1; D) A + 800 kg P2O5 ha-1; E) A + 1200 kg P2O5 ha-1. Vremenske prilike u obje, a naročito u 2012. godini, bile su izuzetno nepovoljne za uzgoj kukuruza. Statistička analiza nije pokazala opravdani učinak fosfatizacije na prinos zrna kukuruza niti u jednoj godini iako je zabilježeno slabo povećanje prinosa kukuruza u odnosu na kontrolu za 8% u 2011. godini, odnosno za 14% u 2012. godini. Sadržaj vlage u zrnu u berbi 2012. godine, bio je niži na tretmanima fosfatizacije. Također je i udio sterilnih biljaka u 2012. godini bio manji. Prinosi zrna u 2012. godini (prosjek 6,36 t ha-1) bili su gotovo za 45% niži u odnosu na prinose zrna u 2011. godini (prosjek 11,01 t ha-1). Takvi prinosi, kao i značajniji izostanak učinka fosfatizacije, posljedica su izrazite suše i visokih temperatura zraka tijekom uzgoja kukuruza.Low level of plant available phosphorus is often a limiting factor for achieving high crops yields. Phosphatization is one of the agro-ameliorative measures that could improve soil fertility and suitability for crops production. The aim of this study was to determine the effect of weather conditions and soil phosphatization on maize grain yields in the region of Odžak municipality (BiH, FBiH) during 2011 and 2012 growing season.The field trial was conducted on alkaline soil poor in plant available phosphorus in spring of 2011. Experimental design was randomized block with four replicates and five treatments as follows: A) control (basic fertilization); B) A + 200 kg P2O5 ha-1; C) A + 400 kg P2O5 ha-1; D) A + 800 kg P2O5 ha-1; E) A + 1200 kg P2O5 ha-1. Weather conditions in both years, especially in the 2012, were extremely unfavorable for maize growing. Statistical analysis didn't prove the phosphatization effect on yield in any year, although there was slightly increase in corn yield on phosphatization treatments compared to the control by 8% and 14 % in the 2011 and 2012, respectively. Grain moisture at harvest and sterile plants contributions in 2012 were lower on plots with increasing rates of phosphorus. Grain yields in 2012 (mean 6,36 t ha-1) were about 45% lower compared to grain yields in 2011 (mean 11,01 t ha-1). Such yields, as well as absence of significant phosphatization effect, are results of extreme drought and high air temperatures during maize growing