Grain Yield of Maize Influenced by Plant Growth Promoting Rhizobacteria (PGPR) and Zinc under Water Deficit Stress

Effect of bacterial inoculation and Zincapplication on yield and yield components of grain maize under water deficit stress condition were studied by experiment as split plot-factorial design with 3 replications at Mahvalat Razavi Khorasan provience, Iran in 2012. Three irrigation cycles (6, 9 and 12 days) and six levels for combination of bacteria (Pseudomonas fluorescens and P. fluorescens) and Zinc(0 and 50 kg.ha-1) were as main plots and sub plots, respectively. Results showed that simple effects of irrigation, bacteria and Zincwere significant on seed number per row, seed number per ear, 1000-seed weight, seed yield and biological yield. As irrigation cycle increased from 6 to 12 days, seed number per ear and seed yield decreased 55.4 and 57.3%, respectively. Also as Zincincreased from 0 to 50 kg.ha-1, these traits significantly increased 6.6 and 10.2%, respectively. Moreover with P. fluorescens application mentioned traits significantly increased 8.6 and 14.7%, respectively as compared with non-bacterial inoculation treatment. Zincsulphate application and PGPR decreased adverse effects of water deficit stress, but under this research conditions, irrigation cycle of 6 days and 50 kg.ha-1 Zincsulphate application and seed inoculation by Pseudomonas recomended.