Barley Grain Mineral Analysis as Affected by Different Fertilizing Systems and by Drought Stress

The effect of different fertilizing systems and drought stress during grain development on grain minerals of barley (Hordeum vulgare L.) was studied in field experiments on a clay-loamy soil during ۲۰۰۷ and ۲۰۰۸ growing seasons. The treatments consisted of three irrigation regimes (main plots) of: Non-stressed (NS, normal irrigation continued until the end of plant physiological maturity), Moderate Stress (MS, irrigation ceased from the beginning of flowering to the beginning of grain filling stage and Severe Stress (SS, irrigation ceased from the beginning of flowering stage up to the end of physiological maturity) along with six fertilizing regimes consisting of no fertilizer application (control) (NF), phosphorous and nitrogen Biofertilizers (BF), ۱۰۰% Chemical fertilizer (NPK) (CF), Vermicompost (VC) ۵ t ha-۱, ۵۰% Chemical fertilizer (NPK)+۵۰% Vermicompost (۲.۵ t ha-۱) (CV), and ۵۰% Chemical fertilizer (NPK)+ Biofertilizer (CB), assigned to the sub plots. Drought stress significantly increased grain minerals of N, Zn and Mn by ۱۲, ۲۷, and ۷% as compared with control (NS), respectively. Average grain nitrogen concentration in chemical fertilizer (CF) treatment was significantly more than those in the other treatments followed by integrated fertilizing systems (CB and CV). Phosphorous concentration in grains produced in BF fertilizer medium was significantly higher than those in other treatments. Grain Fe and Zn concentrations increased through vermicompost application. However, Mn concentration was higher in grains fertilized with chemical fertilizer. It can be concluded that in barley production under water deficit conditions, grain mineral quality could be improved through integrated fertilizer application.