Nanomaterials and Their Toxicity to Beneficial Soil Microbiota and Fungi Associated Plants Rhizosphere

Abstract

Previous decades have witnessed an exponential increase in the research and application of nanotechnology in agricultural sector. A diverse array of nanoparticles (NPs) are known to find usage in agricultural sector. Their functions can range from water storage to delivery of nutrients and fertilizers. In addition, the inherent possession of biocidal activity by different metal and metal oxide NPs have put forward their application to combat different bacterial and fungal pathogens. However, despite of several gains offered by the nanotechnological-interventions in agricultural systems, they are also known to possess inherent toxicity towards plant growth promoting rhizobacteria (PGPR) and beneficial fungi. The continuous exposure of NPs lead to induction of oxidative stress, production of reactive oxygen species, disruption of cell membrane and DNA damage in the beneficial soil microbiota and fungi associated to plant rhizosphere. The regular application of NPs marks their accrual in the soil systems and their concentration keeps on increasing with each crop cycle. In addition, they also keep on accumulating in different plant tissues, thus can be equally lethal for the consumers. Therefore, a critical assessment of their inherent toxicological attributes and off-target effects before their field application is strictly needed. In this chapter, we have summarized the toxicological attributes of different NPs towards the PGPR and beneficial soil fungi.