The effects of plant growth promoting rhizobacteria (Azospirillum, Pseudomonas) on growth and yield of corn (Zea mays L.).

Plant growth promoting rhizobacteria (PGPR) with various mechanisms including enhanced nutrients availability and uptake can improve plant growth. The study arrangement was factorial based on randomized blocks design. Bacterial strains of Azospirillum (A. lipoferumDSM1691، A. brasilense DSM1690) and Pseudomonas (P. putida strain R-168، P. fluorescens strain R-93، P. fluorescens DSM 50090، P. putida DSM 291) as well as a control treatment، were used to inoculate the seeds. The results indicated that from 75 and 90 days after sowing till the end of growth season، plants inoculated with Azospirillum and Pseudomonas produced higher total and grain dry weight، compared with control. At the end of growing season the highest total dry weight (DW) was obtained from inoculation with A. lipoferumDSM1691 and A. brasilenseDSM1690 and also the highest grain weight was obtained from inoculation with A. brasilenseDSM1690. The highest total DW was related to inoculation with P. putida R-168 and the highest grain weight was related to inoculation with P. putida R-168 and P. fluorescens R-93.