Visualization of synergistic interaction between inorganic nanoparticle and bioinoculants

Enhanced production of quality food to feed a burgeoning human population has become a challenge for the globe under the present environmental scenario with less water and cultivable land. Continuous attempts are being made to implement new agricultural practices to enhance food production. Use of plant growth-promoting rhizobacteria (PGPR) as bioinoculants and nanoparticles has demonstrated their potential in practicing sustainable agriculture. The present study aimed to analyse the PGPR properties of two bacterial isolates and their interaction with nanosilicon dioxide (nSiO₂) based on their growth pattern and structural modification. Both the bacterial isolates utilized citrate and solubilised zinc and produced amylase, cellulase, and exopolysaccharides which were involved in plant growth promotion. A consortium of the bacterial cultures showed better Zn solubilisation in comparison to individual bacterial isolates. In vitro antifungal activity against Talaromyces sp. was observed in both the bacteria. A positive influence of nSiO₂ on the growth and number of colony-forming unit (CFU) of both bacterial isolates was observed. Scanning Electron Microscope (SEM) analysis of the bacterial isolates grown in the presence of nSiO₂ did not show any inhibitory effect on the morphological structure of the bacterial cells. This study indicated that nSiO₂ showed a positive impact on PGPR and can be further used in making bioformulation to improve the survival of bioinoculants in the agricultural sector.