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Present investigation was carried out to identify plant growth promoting rhizobacterial isolates for abiotic stress tolerance. To achieve this bacterial isolates were isolated from different rhizospheric soils of Telanagana and screened for plant growth promoting properties and tolerance to different abiotic stresses such as pH, temperature, salt, drought and heavy metals. Such PGPR will be helpful for efficient management of abiotic stresses in crop production. Rhizospheric soils from normal, salt affected, drought affected and bulk soils were collected from different places of Telangana state. From all soil samples, based on cultural, morphological and biochemical characterization it was found that forty four were of Bacillus spp. Among the forty four (44) Bacillus isolates, twenty eight (28) isolates were showing plant growth promoting properties. These positive isolates tested for abiotic stress tolerance to pH, temperature, salt, drought and heavy metals (As and Cd). Four isolates were showed growth at pH range from 4-12 (BS 1, BS 3, BS 14, BS 18), five isolates were showed tolerance to 1.5 to 20 % of NaCl concentration (BS 1, BS 3, BS 14, BS 18, BS 42, six isolates showed tolerance to temperature from 20ºC -50ºC (BS 10, BS 14, BS 18, BS 27, BS 37, BS 43), four isolates showed tolerance to water potential from - 0.05 Mpa to- 0.73 Mpa (BS 4, BS 10, BS 18, BS 33).

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Present in vitro experiment was carried out to identify plant growth promoting rhizobial isolates for abiotic stress tolerance. Rhizospheric soils from normal, salt affected, drought affected were collected from different places of Telangana state. From all soil samples, twenty one rhizobial isolates were collected. Among the twenty one isolates, eleven isolates were showed different plant growth promoting properties. The results of different in vitro abiotic stress tolerance of isolates reveals that, only one isolate showed tolerance to temperature from 20ºC-50ºC (YR-21), three isolates were showed tolerance to temperature from 20ºC -45ºC (RR-1, GR-5, GNR-8), one isolate was showed tolerance to temperature from 30ºC-45ºC (MR-11), only one isolate were showed tolerance to temperature from 30ºC -40ºC (ASR-17). Two isolates showed tolerance to water potential from -0.05 Mpa to-0.15 Mpa (RR-1, RR-3), three isolates were showed tolerance to water potential from -0.05 Mpa to -0.30 Mpa (GNR-8, ASR-19, YR-21), only one isolate showed tolerance to water potential at -0.05 Mpa (GNR-7).

Plant growth-promoting rhizobacteria (PGPR) contribute to an increase in crop yield through an environmentally friendly method, therefore eight rhizospheric bacteria, two of each genera Bacillus, Pseudomonas, Azotobacter and Azospirillum were examined for their efficacy to solubilize mineral nutrients using atomic absorption spectrophotometry and a flame photometer. Their potency to produce phytohormones, synthesis biocontrol components and their compatibility with pesticides using in vitro assays was studied. All of the chosen bacterial isolates proved positive for the above-mentioned Plant Growth Promoting traits. Among the eight bacterial isolates Pseudomonas isolate P69 showed the highest phosphorous solubilization efficiency of 190.91 % and another isolate P48 produced a maximum of 27.63µg mL-1 of gibberellic acid, Bacillus isolate B120 could solubilize maximum amount of ZnO and ZnCO3 accounting for 21.3ppm and 25.9ppm, respectively, not merely in terms of solubilization when compared to the other isolates, B120 produced the highest levels of HCN (77.33 ppm TCC) and siderophores (48.87psu). On day 9 after inoculation, Azotobacter isolate AZB17 performed effectively in potassium solubilization of 6.25g mL-1 with a pH drop to 3.83. The Azospirillum isolate ASP25 outperformed all other isolates in terms of IAA production (22.64g mL-1) and Bacillus isolate B365 was found to be more compatible with eight different pesticides used in the field at varying concentrations. All of these factors point to the possibility of using these bacterial isolates B120, P48, P69, AZB17, and ASP25 as biofertilizers in sustainable agriculture.