The beneficial microbial-plant interaction plays important role in the soil health, crop growth and productivity. Plant growth promoting rhizobacteria (PGPR) are such beneficial microorganisms, which in association with plant roots not only promote their growth but also help in counteracting the detrimental effects of soil stresses. Salt stress is one such stress, frequently confronted by the plants. The present study aimed at isolation and identification of PGPR inhabiting the mungbean rhizosphere, testing them for salt (NaCl) tolerance and subsequently in salt-supplemented mungbean crop. For this purpose, two salt-tolerant bacterial strains belonging to genus Pantoea and Enterococcus, characterized for their P-solubilization ability, indole acetic acid and siderophore production were selected. These two PGPR were further evaluated for their effect on the salt-stressed mungbean plants, grown at two salt concentrations (5 and 10 dS/m). The plants treated with the combination of PGPR showed better performance in growth (16-37 %) and yield (22-32 %), under salt stress, as compared with control. The increasing salt concentration was found to increase the membrane damage, Na ? concentration in the plants. PGPR treatments effectively reduced the Na ? concentration (17-41 %), membrane damage (1.1-1.5 folds) and enhanced the antioxidants i.e. ascorbic acid (8-26 %) and glutathione (10-30 %) in salt-stressed plants, in comparison to uninoculated stressed plants. Overall, the results indicated that both PGPR were effective as stress mitigators however, in combination they showed relatively better improvement in growth, yield as well as oxidative parameters of the salt-affected plants. These findings about the effects of native salt-tolerant PGPR Pantoea and Enterococcus sp. in mungbean crop are novel.

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Soil and associated stress conditions not only influence dwelling microbial populations and soil ecosystems but also affect growth and yield of plants. Major soil stress includes salinity, drought, and metal contamination. Due to burgeoning populations and expanding food demands, it has become imperative to alleviate the stressful soil conditions so that the crop production is increased and, consequently, the food demands are fulfilled. Different strategies are followed to resolve this problem, and one such approach involves exploiting microbial potential for plant's benefit. The multifunctional microscopic life-forms are already known for their applications in industries, medicine, and agricultural field. One of the major attributes of microbes from agronomic point of view is their ability to solubilize difficultly available forms of soil phosphorus. Phosphate-solubilizing microbes are also known to produce enzymes, siderophores, and growth hormones; embellish plant growth and biocontrol activity; and improve soil properties. Such microorganisms possessing attributes, beneficial for plants are termed as plant growth-promoting rhizobacteria (PGPR). There are plentiful reports on bacterialmediated plant growth promotion under nonstressed conditions although fewer reports are available on their effects under stressed condition. The bacterial ability to enhance tolerance of plants in stressed soils and the impact of PGPR consortium (mixture) on different crops are highlighted. The major idea here is to consolidate the fact that PGPR consortium can be used directly in stress-affected soil with an aim to refurbish soil conditions to foster crop productivity in stressed soils.