Response of Maize to Nutrients Foliar Application Under Water Deficit Stress Conditions

Problem statement: To investigate the effect of nutrient application on agronomical characteristic and water use efficiency under water deficit stress of hybrid maize 704, an experiment was arranged in a split plot factorial based on a complete randomized block design with four replicates in the research station of Islamic Azad University-Arak Branch, Iran in 2007. Approach: Main factors studied were four irrigation levels including irrigation equal to crop water requirement, water deficit stress at eight-leaf stage (V₈), stage of blister (R₂) and stage of filling grain in the main plot. Combined levels of selenium treatment (without and with application 20 g ha^-1) were applied 2 weeks before execution of water stress treatment and micronutrients (without and with application) that was provided by specific fertilizer for maize called "Biomin", which contained Fe, Zn, Cu, Mn, B, Mo and Mg in the form of foliar application at six-leaf stage and 1 week before tasseling stage at the rate of 2 L ha^-1 were situated in sub plots. Results: Results indicated that effect of water deficit stress on 1000 grain weight, grain yield, harvest index and water use efficiency at different growth stages was significant at 1% level. Water deficit stress decreased grain yield 33% in grain filling stage as compared with control. Using selenium increased mentioned traits but the increase was non significant. Effects of twofold interactions of water deficit stress and selenium showed that using selenium in water deficit stress condition increased measured traits as compared with treatment without selenium. A negative antagonistic interaction was found between selenium and micronutrients on some measured traits. In between treatments of water deficit stress, highest grain yield (8159.33 kg ha^-1) was obtained from combined treatment of water deficit stress at eight-leaf stage with selenium application and without micronutrients which compared with treatment of irrigation equal to crop water requirement, without selenium and microelements did not differ significant. Conclusion: According to the results of experiment, using microelements in optimum water availability and using selenium in water deficit stress condition increased mentioned traits as compared to treatments control.