Prospecting the interactions of nanoparticles with beneficial microorganisms for developing green technologies for agriculture

Abstract Agriculturally important microorganisms are environment-friendly options which regulate the efficiency and accessibility of nutrients to crop plants, thereby improving fertility by enriching the biodiversity and nutrients in soil. To augment the efficiency of microbial agents, several researchers have explored the unique properties of nanoparticles (NPs), particularly their size-activity relationships. Nanofertilizers such as ZnO nanoparticles synthesized using soil fungi or nanopyrite dressings are known to enhance nutrient mobilization and their uptake in plants; however, published reports on the intricate reactions between nanoparticles and agriculturally beneficial microorganisms are scanty. Several nanoparticles, particularly those of silver or copper exhibit inhibitory effects on microorganisms, but the effects of sub-lethal doses or long-term exposure on pathogens are less understood. This review addresses aspects related to interactions of nanoparticles with microorganisms, including their uptake and accumulation, besides both the stimulatory and inhibitory roles played by nanoparticles in plant growth and productivity, particularly in the agricultural scenario. Several phytopathogens cause severe crop and monetary losses; the benefits of using nanoparticles in agriculture as biocontrol agents needs intensive experimentation on a case to case basis, as this can be a valuable and significant strategy in the coming years.