A detailed study Biofilm forming Polyextremophilic Firmicutes from the Himalayas and exploration of their plant growth promoting potential

Abstract Polyextremophily has been an intriguing point of interest among the scientists, a phenomenon in which organisms can thrive in combinations of multiple extreme conditions. In the foreseeable future, climatic conditions are predicted to change, and agriculture is bound to suffer with these changes in the environment. The situation necessitates some solutions that can ensure agricultural sustainability, in the changed, harsh environmental conditions without more toxic chemical intrusions in the agricultural fields. The bacterial strains Brevibacillus parabrevis BRAM_Y3 and Mesobacillus subterraneous BRAM_Y2 in this study, isolated from the waters of Yamunotri showed incredible properties of Polyextremophily like tolerance to not only temperatures as high as 70°C, pH range (4-10), saline, drought, UV and heavy metals such as mercury, iron, silver and arsenic but also their two-dimensional and three-dimensional combinations. The elevated levels of biofilm formation when subjected to stress revealed their property of using biofilm as their shield against harsh conditions. Furthermore, they were studied for their plant growth promotion like nutrient sequestration (N, P, K, plant hormone production etc.) biocontrol properties (cell wall degrading enzymes, siderophores, VOCs etc.) and the ability to confer abiotic stress resistance (ACC Deaminase) to plants. The in-vivo experiments conducted on Zea mays. L yielded conclusive and promising results. The use of these polyextremophiles for agriculture in harsh environments may serve as a solution for the global warming mediated climate and environmental changes. Competing Interest Statement The authors have declared no competing interest.