Chromium-Reducing Bacteria Mediated Biopriming: Exploiting A Sustainable Strategy for Immunity Against Blast and Remediating Chromium Stress

Abstract

Rice production is vulnerable to several pressures; one of the main biotic stresses is blast disease, which is brought on byMagnaportheoryzae and can potentially wipe out the entire crop under extreme circumstances. Microbial-mediated seed and root prime in plantsenhance defense against a broad range of pathogens by jasmonate (JA) and ethylene (ET) signaling mediated induced systemicresistance (ISR). The present work demonstrates some selected microbes like Bacillus cereus, Pseudomonas aeruginosa, Staphylococcusgallinarum, Staphylococcus hominis, Enterobacter cloacae show an antifungal effect against the rice blast pathogen (Magnaportheoryzae). Rice (Swarna) seed and root priming with these bacteria enhance ISR in rice against rice blast disease. The MYB transcriptionfactor gene MYB72 and NPR1, NPR3, and NPR4 genes function as long-distance ISR signaling molecules highly expressed in the rice(Swarna) root by co-cultivation with the bacteria in the rice’s rhizosphere. These bacteria also resist ~1100 ppm of chromium stress andreduce around 88.94% of Cr6+ to Cr3+ within 50 days in chromium-contaminated soil. Because Cr3+has a reduced ability to enter cells, itis less poisonous than Cr6+, which is more toxic and soluble and can be transported to cells more easily. The carcinogenic andmutagenesis properties of hexavalent chromium Cr6+ make it a hazardous substance. These bacteria act as a key factor against abioticand biotic stresses.