- - - Crop and Horticultural Research Department, Ardabil Agricultural and Natural Resources Research and Education Center, AREEO, Moghan, Iran.
- - - Department of Plant Breeding and Biotechnology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

To assess the grain yield, plant height and superoxide dismutase (Cu/Zn-SOD) activity, and its expression responses of maize to water deficit stress, a field experiment using a split-plot design based on randomized complete block design was performed with three maize hybrids, SC۷۰۴, SC۷۲۰ and NS۶۴۰, under control and water-deficit stress conditions at the Research Station of University of Tabriz, Iran. The results indicated that water deficit stress reduced grain yield and plant height. Electrophoretic analysis for Cu/Zn-SOD based on sensitivity to KCN and H۲O۲ inhibitors was carried out using ۸% slab polyacrylamide gels. The gene expression of Cu/Zn-SOD by using Real-time PCR in maize hybrids showed that water deficit stress increased Cu/Zn-SOD expression. SC۷۰۴ with higher grain yield, plant height and Cu/Zn-SOD activity ranked as a drought-tolerant hybrid in this study. It can be concluded that the increase in Cu/Zn-SOD expression may decrease damage caused by water-deficit stress in maize.

Antioxidant enzyme, Electrophoresis, Gene, Grain Yield, Isoform, Plant Height