Fascinating Dynamics of Silicon in alleviation of heat stress Induced oxidative damage in plants

Si is one of the major elements needed by plants in order to cope with adverse environmental conditions, and is considered a quasi-beneficial element. Si is involved in root growth and differentiation, transportation of other elements, carbon assimilation, activities of key enzymes, chelation of toxic elements, regulation of redox system, distribution of photosynthates, modulation of tolerance and stabilization of grain quantity and quality under stress. Stressed plants, however, seem to benefit more from Si. Si has been reported to trigger the function of various signalling cascade like mitogen-activated protein kinases (MAPKs), calcium-dependent protein kinases (CDPKs), Reactive oxygen species (ROS), antioxidant, antioxidant enzyme network and phytohormones signalling under adverse conditions. It has indirect effect on the expression of stress-responsive TFs and stress-associated genes and proteins like heat shock proteins (HSPs) which is involved in modulating the tolerance of the plant under stress. Additionally, it regulates the function of various transporters, including ATP-binding cassette (ABC) transporters that are believed to be involved in stabilizing lipid distribution in cell membranes under heat stress (HS), as well as regulating carbohydrate, protein, and lipid accumulation in grains. In-depth characterization has been possible with the advent of technology, and Si has been reported to involve in flowering, pollen tube growth, and fertilization. Large number of Si-responsive transcripts has been identified through transcriptomic approach. In plants treated with Si, high nutrient density has been observed in the grains. In the present scenario, there is a need for developing Si-based technology to enhance plant tolerance against HS without compromising grain quality. In the near future, this cheap and environment friendly technology will pave the way for mitigating the effects of stress in crops.