Silicon and Plants: Current Knowledge and Future Prospects

Silicon (Si) is the most copious element of existence in the lithosphere but still it has not been added into the essential element list. The imperative role of Si in triggering growth and development of plants has been identified. It is of paramount importance in regulating overall physiological and metabolic characteristics of the plants. Being considered as a non-essential element, it has been known to occur at about 30%, majority of its presence is there in rocks as mineral salts. It has been regarded as multitalented or quasi-element on earth's crust that can be efficiently taken up by plants and translocated further towards aerial parts via transpiration phenomenon. It has also been known to mitigate different biotic and abiotic stressed conditions from plants as the need of the hour owing to its eco-friendly nature. However, the mechanisms associated with their stress attenuation are associated with Reactive Oxygen Species (ROS) scavenging, activation of antioxidative defense responses and phytohormonal signaling. Also, biotic stress factors can be ameliorated through accumulation of Si within epidermal tissues or pathogenesis-related host defense mechanisms. To explore further, omics-mediated studies have been further discussed to shed light on the stress mitigating processes. Further, to improve our understanding for Si-mediated benefits in plants we need to explore the molecular mechanisms of Si uptake, transport and gene expression studies revealing their mitigate properties. In the present review, we have evolved the Si-based studies in plants associated with its transport, uptake and accumulation. Apart from this, we have also discussed about their role in ameliorating stresses from plants by activating their defenses. Moreover, their roles in plant hormonal crosstalk have also been elucidated. Above all, we have also revealed the role of Si-Nanoparticles (SiNPs) in improving stress potential of plants along with stimulation of plant productivities via omics-based approaches.