Effect of application methods of phosphate and zinc sulfate fertilizers on water use efficiency and qualitative characteristics of corn under water deficit stress

To study the effects of phosphate and zinc sulfate fertilizers application methods on water use efficiency and qualitative characteristics of corn underwater stress, an experiment was conducted in split plot factorial arrangement on randomized complete block design with three replications at research farm of the Bu Ali Sina University in 2014. Three levels of irrigation after 60, 90, and 120 mm evaporations from evaporation A pan were assigned in the main plots and two factors including phosphate fertilizer application methods (broadcasting and band placement) and zinc sulfate (non, foliar, and soil application) were assigned in sub-plots. Measured traits included protein percent in the grain, phosphorus and zinc content in the grain, and water use efficiency. Results showed that at severe water deficit stress, foliar application of zinc sulfate and band placement phosphate fertilizer compared to no zinc sulfate in the same application increased grain protein by 12%. The highest water use efficiency (1.50 kg grain per cubic meter of water) was obtained from treatment after 90 mm evaporation and band placement of phosphate and foliar application of zinc sulfate. In severe water stress conditions, band placement phosphate increased grain phosphorous content by 26%. Eventually, the highest and the lowest grain zinc concentration were 16.58 and 11.53 mg kg-1, respectively.