Heavy Metal Resistant PGPR Bioinoculants as Promising Bioremediating Agents for Modulation in Plant Growth under Chromium Metal Stress

Nuzhat Jamil, Muhammad Yasir, Ambreen Ahmed


Chromium generally hinders plant growth, but bacterial inoculations by following different mechanisms can enhance tolerance against heavy metal stress in plants. Characterization and identification of the bacterial strains which have capability to improve growth of plants growing under chromium stressed environment by reducing uptake of metal was the main objective of this present study. For this purpose, chromium tolerant bacterial strains were isolated from tannery effluents from industrial area Kasur, Pakistan and finally three competent bacterial isolates showing minimum inhibitory concentration as 300µg/ml were selected for further study. After that 16S rRNA genetic analysis was used for molecular characterization of these bacterial isolates. Seeds of Helianthus annus were inoculated with these bacterial isolates and grown under chromium contaminated soil to determine their effect growth attributes of plants. All the growth attributes of plants, biomass production, stress tolerance index and seedling vigor index was measured. The present study represents that bacterial inoculation of seeds has capability to improve growth attributes of plants growing in heavy metal stressed environment and counteract the damaging effects of toxicity of heavy metal chromium. The objective of this study is to use bacteria as emergingy ecofriendly bioremediation approach to grow important crops in heavy metal contaminated areas.


Bacterial isolates; Chromium resistance; Growth attributes; Helianthus annus; Seed germination; Seedling vigor index; Stress tolerance index

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DOI: https://doi.org/10.33687/planthealth.01.01.4533


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