ABSTRACT
Advancement in nano-research for the development of agricultural products and nano-agri inputs in recent years has opened a new paradigm in the field of agriculture and the food sector. This pro-gress in knowledge is expected to help in the development of sustainable agri-practices for in-creased food production in the coming years. Application of nanomaterials (NM) in agriculture has been mainly aimed at the precise delivery of fertilizers and pesticides, their controlled release rates, increased nutrient use efficacy, and early detection of plant disease. However, the effects of metal-lic nanoparticles (MNPs) on agriculturally relevant plants are not well understood. Due to their ul-tra-small sizes, NMs acquire a higher tendency to interact with biological systems, which could result in an adverse impact on plants, human health, and the environment. Lack of in-depth re-search regarding the interaction of NMs with plants, bioaccumulation, retention, and transfer to dif-ferent trophic levels obstructs the usage of these NMs in the agricultural sector. Optimization in the design of NPs and their application dosage remains to be achieved to minimize the risk of potential toxicity to plants, the environment, and humans. In this review, we discuss (i) uses of MNPs in agriculture as nanofertilizers (NFs) (ii) routes of plant exposure to MNPs - direct (application into soil/foliar spray) and indirect (air/water stream, etc.), (iii) effects on plants, (iv) effects on soil mi-crobial environment, (v) current knowledge about mechanisms for MNPs’ uptake, bioaccumula-tion, bio-magnification, (vi) Mechanism underlying phytotoxicity caused by MNPs, (v) global reg-ulations on nano-agri inputs. Based on the observations made from the above-mentioned points, suggestions have been provided for safer application of NMs in agriculture.
