Effect of Zinc Oxide Nanoparticles on Some Biochemical and Morphological Characteristics of Wheat under Drought Conditions

The aim of this study was to investigate the effect of zinc oxide nanoparticles on some biochemical and morphological characteristics of wheat under drought stress and reduction of drought effects under the influence of zinc nano oxide foliar application.

A factorial experiment was conducted in a completely randomized design with three replications in the University of Mohaghegh Ardebili in 2016-2017. The first factor was drought stress at three levels (35, 60 and 85% of field capacity), the second factor was wheat cultivars (Mihan, Heydari, Sysons and Gasogen) and the third factor included foliar spraying with zinc oxide nanoparticles with concentrations of 0, 0.5 and 1 g.l-1. The foliar application was performed in three-leaf stage and three days after foliar application, drought stress was applied based on field capacity and sampling was performed ten days after stress.

The findings showed that under ZnO treatment, the amount of soluble protein, soluble sugar, proline, plant height and grain weight increased. As the severity of drought stress increased, the amount of protein decreased, but the amount of proline and soluble sugar increased. Stress also decreased plant height, dry and fresh root weight, as well as grain yield (15.95% of grain size and 11.93% of grain weight). Spraying wheat plants with zinc nano oxide in the Mihan and Heydari cultivars moderated the effects of stress, and in the cultivars of Sysons and Gascogen increased the plant's defense mechanisms against the destructive effects of drought stress.

In general, foliar feeding of ZnO at a concentration of 0.5 g.l-1 makes wheat plants tolerant to drought stress.