Assess Effect of Nitrogen Fertilizer and Phosphorous Biofertilizers (Azospirillum and Pseudomonas) on Barley Crop Production and Seed Protein Content

BACKGROUND: Azospirillum is effective in biostabilization of nitrogen and Pseudomonas is effective in dissolving soil phosphorus. OBJECTIVES: Current study was conducted to assess effect of different level of nitrogen and biofertilizer on seed yield, its components and protein content. METHODS: This research was carried out via spilt plot factorial experiment based on randomized complete blocks design with three replications along 2014-2015 year. The main factor included nitrogen (N0%=0 or control, N50%=75, N75%=112.5, N100%=150 kg.ha-1). The sub factor at first consisted Azospirillum (Azo0: non use of Azospirillum or control, Azo1: use of Azospirillum) and then Pseudomonas (Pse0: non use of Pseudomonas or control, Pse1: use of Pseudomonas). RESULT: The results showed that the application of nitrogen fertilizer had a significant effect on seed protein content, seed protein yield, plant height and seed yield at 1% probability level, also inoculation of Azospirillum increased the effect of nitrogen fertilizer on these traits. Mean comparison result of different level of Pseudomonas indicated that maximum seed yield (4800 kg.ha-1) was noted for Pse1 and minimum of that belonged to control treatment. So Pseudomonas inoculation increased seed yield by 8% compared to the control treatment (no bacterial inoculation). As for Duncan classification made with respect to interaction effect N × Azo the maximum and minimum amount of seed yield belonged to N100% and Azo1 (5710.9 kg.ha-1) and control (3981.3 kg.ha-1). Inoculation of the plant with Azospirillum increased the seed protein content by 14.8%. Also inoculation of Pseudomonas caused the highest amount of seed protein content of 13.56 (g.100 g-1). CONCLUSION: Inoculation of Pseudomonas fluorescence also had a significant effect on all the mentioned traits. Inoculation of Azospirillum and 75 kg N ha-1 significantly increased seed yield and the use of Azospirillum led to save 25% of the nitrogen fertilizer and can be advised to producers.