Mineral composition of the common winter wheat grain grown in different tillage and nitrogen levels

Abstract

The content of mineral elements is a fundamental component of wheat grain quality and varies depending on applied cultural practices. The aim of the study is to examine the impact of wheat production methods on the composition of mineral elements in the grain. The field experiment was conducted in completely randomized blocks on luvic chernozem soil of the Faculty of Agriculture "Radmilovac".The variety of common soft wheat Ilina (Triticum aestivum ssp. vulgare), was cultivated in three tillage systems - conventional, mulch and notillage. In addition to basic cultivation fertilization treatment with NPK fertilizers in the autumn, two different amounts of N in top dressing (60 and 120 kg/ha N), were added in spring. Standard measures in wheat production were applied and the harvest was carried out at the end of June. Concentrations of 18 eighteen elements (As, Al, Ba, Ca, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Ni, S, Sr, P, V and Zn) in wheat grain samples were determined by means of inductively coupled plasma with optical emission spectrometry (ICP–OES). The results indicated that the concentrations of the studied elements in the wheat grain were significantly affected by the tillage systems and fertilization rates (p < 0.001), as well as the interaction of these two factors. The lowest content of the examined macroelements (K=3052mg/kg and P=3617 mg/kg), as well as the highest concentration of microelements, such as (Cu=5.104 mg/kg and Ni=0.517 mg/kg), was observed in the grain produced in the conventional tillage. The highest concentrations of Fe 48.28 mg/kg, Ba 2.991 mg/kg, and Mn 24.4 mg/kg were detected in the grain treated with 60 kg/ha N. Reduced tillage and reduced nitrogen fertilization had significantly higher positive effect on the concentration of nutritionally important minerals (Ca, Fe, K, Mg, P and Zn) in respect to the conventional tillage with higher levels of nitrogen. Results indicate that in semi-arid climate reduced soil tillage could serve as an important part of sustainable cropping system to facilitate food security