Bacteria-Based MnO Nanoparticles Alleviate Lead Toxicity in Tomato Seedling Through Improving Growth Attributes and Enhanced Gene Expression of Candidate Genes

Lead (Pb) is a well-recognized toxic trace element that is harmful for both plants and humans. In this study, the research work strived to fabricate nanoparticles (NPs) incorporating ‘features’ of Bacillus subtilis and manganese oxide (MnO). MnO-NPs were synthesized in the filtrate of B. subtilis and used for the seed priming of tomato, to mitigate lead (Pb) toxicity. Fourier transform infrared spectrum (FTIR) described the presence of carboxylic acid, alkenes, and alkyl halides on the surface of MnO-NPs, that serve as stabilizing and reducing agents. X-ray diffraction revealed MnONPs as 22 nm crystalline structures while scanning electron microscopy (SEM) displayed nano-flower structure of MnO-NPs. The energy dispersive X-ray (EDX) analysis determined the mass percentage of manganese (38.27