Crosstalk of nanoparticles and phytohormones regulate plant growth and metabolism under abiotic and biotic stress

In the era of climate change, plants are facing various and unprecedented environmental stresses. Both biotic and abiotic stress factors are very important constraints that adversely affect the plants’ developmental and metabolic processes. In order to cope with the environmental challenges, plants have evolved a variety of defense mechanisms at various levels by modifying their morphological, physiological, anatomical, biochemical features up to molecular level. Currently, nanotechnology is a blooming innovative area in the field of plant science with new ideas for understanding the appropriate mechanism of plants survival under stress. Nanoparticles are regarded as regulatory molecules for plants that can modulate a wide range of physiological and biochemical processes along with activation of the anti-oxidative defense system, hormonal regulation, and stress-related gene expression. The plant growth hormones also act as stress regulatory molecules and known to involve in various signaling cascades under the exposure of nanoparticles. Under the stress, over production of reactive oxygen species (ROS) are measured which can be regulate with the help of nanoparticles. Recently, few studies reported that nanoparticles can ameliorate the stress consequences with the regulation of phytohormones signaling. However, the appropriate mechanism of crosstalk between nanoparticles and phytohormones biosynthesis is still at infancy stage. Thus, it is required to understand the nanoparticles-related regulation of phytohormones synthesis and their signaling under stress conditions for the advancement and sustainability of plant production. In this review, we are elucidating the crosstalk of nanoparticles and phytohormones along with their potential regulatory role under plant stress conditions.