Introduction: Increasing demand for food due to rapidly increase in global population, it is necessary to meet the food requirements without degrading the environment. In cultivated zones, around highly populated areas, there is excessive use of fertilizers. There is a requirement to opt for natural or biological fertilizers to substitute the chemical fertilizers, due to the increasing demand for agriculture sustainability. Microbial Inoculants could be effective for crop production improvement without negative effects on the environment.

Objective: The present study focuses on the efficacy and utilization of Bacillus subtilis (ATCC 6633) and Pseudomonas sp. (ATCC 27853) as microbial inoculant to analyse the growth rate and of mustard (Brassica nigra) and carom seeds (Trachyspermum ammi) and compare with untreated seeds. Bacterial culture in the form of seed treatment and foliar spray were used as microbial Inoculant for the growth of plant.

Results and Discussion: The major seed treatment effect was observed with Bacillus subtilis that showed antifungal activity against phytopathogens. Initially, faster germination percentage was found with the carom seeds with seed treatment showed the best results, with 90% and 82% in 3 days compared to the untreated seeds and mustard seeds. Mustard Seeds treated with Bacillus subtilis showed faster plant growth rate after sowing in terms of increase in shoot length 11.6cm, 13.2 cm and root length 2.3cm, respectively, after 20 days. Spraying treatment resulted in shoot length 6.2 cm and root length 1.4cm, respectively, higher than compared to the control.

Conclusion: Bacillus subtilis ATCC 6633 and Pseudomonas sp. (ATCC 27853) microbial inoculum can be used as Microbial Inoculants, and they could act as an environmental-friendly and economical alternative to synthetic liquid fertilizer for promoting sustainable agriculture.