## 4. Discussion
In our study, strains BR5, OR15, and RB13 produced IAA with amounts comparable to those reported by [PERSON] et al. [37] produced by _Azotobacter_, _Pseudomonas_ and _Bacillus_ strains isolated from rhizosphere soil. Roots treated with IAA-producing strain _Pseudomonas putida_ improved canola seed roots by 35-50% compared to an IAA-deficient strain [36]. Determining the germination potential of seeds under saline conditions is another consideration when selecting PGPR effective in salt stress tolerance. Final seed germination and the germination rate of wheat decreased in the presence of salt, which was common in several plant species [38]. Salt stress vigorously affects germinating seeds compared to growing plants, as germination normally occurs in soil surfaces where soluble salts accumulate due to evaporation. Restricted water availability and ion accumulation lead to reduced germination, many changes in the enzymatic and hormonal activities of the seeds and affect the structural organization of the germinating embryo [39]. The treatment of durum wheat seeds with the bacterial strains and their combinations considerably improved the germination parameters with and without added salt. The effect of seed inoculation by the different strains was visible on the cumulative germination rate and the final germination percentage. The best levels were obtained after inoculation with the BR5 strain and the combination of the three strains. The use of salt-tolerant bacteria was an effective strategy for seed priming and eventually plant yield [32]. Germination vigor indices were also significantly improved after the inoculation with bacteria and their combinations with or without salt. A significant increase in the vigor of the seedlings would be produced by a better synthesis of auxins by PGPR which directly improves different cell defense systems triggering early germination even under stress conditions. Quick and healthy seed germination is the first step in achieving vigorous plant production [40]. The effect of inoculation with rhizobacteria and their combination on the plant growth of wheat was carried out in pots on three soils of different salinities. This test makes it possible to verify the competence of the strains in the possibility of using them as biofertilizers for plant crops on saline soils or irrigated by saline waters. For this, the soils used were taken directly from the periphery of the Chotts and different places, having high electrical conductivity values (S2 = 3.81 and S3 = 2.80 mS/cm) in comparison with a non-saline control soil (S1 = 0.48 mS/cm). The results obtained showed that the growth of wheat represented by its morphological parameters was significantly affected by salinity and that bacterial inoculation had a significant beneficial effect on these parameters. In this study, salinity was observed to reduce plant height, root length, and fresh and dry weight of shoots and roots. These results were similar to those of many studies [3; 20; 24]. The most common effects of salinity are loss of turgor, reduced growth, resulting in smaller leaves, shorter stature, early senescence, loss of cell integrity, tissue necrosis, and even plant death [27]. However, in this test, inoculation of wheat plants showed a positive effect at all salinity levels for plant height, root length, and fresh, dry shoot and root weight (even minimal for the most stressful soil 2). These results suggested that stress was lower in the inoculated plants, with evidence that inoculation can effectively reduce saline stress. PGPR induce changes in the outer layers of the root cortex allowing increased cell division at the ends of wheat seedlings [41]. This phenomenon could be attributed to the production of auxin, inhibition of ethylene synthesis, or mineralization of nutrients [28], or even decreased absorption of toxic ions [41]. Chlorophyll analysis is one of the important biochemical parameters as an indicator of salt tolerance and plant protection capacity [32].