AJPS  Vol.9 No.7 , June 2018
Versatile Potentiality of Silicon in Mitigation of Biotic and Abiotic Stresses in Plants: A Review
Abstract: The “quasi-essential element” silicon (Si) is not considered indispensable for plant growth and its accumulation varies between species largely due to differential uptake phenomena. Silicon uptake and distribution is a complex process involving the participation of three transporters (Lsi1, Lsi2 and Lsi6) and is beneficial during recovery from multiple stresses. This review focuses on the pivotal role of silicon in counteracting several biotic and abiotic stresses including nutrient imbalances, physical stresses together with uptake, transport of this metalloid in a wide variety of dicot and monocot species. The knowledge on the beneficial effects of silicon and possible Si-induced mechanisms of minimizing stress has been discussed. Accumulation of silicon beneath the cuticles fortifies the cell wall against pathogen attack. Si-induced reduction of heavy metal uptake, root-shoot translocation, chelation, complexation, upregulation of antioxidative defense responses and regulation of gene expression are the mechanisms involved in alleviation of heavy metal toxicity in plants. Silicon further improves growth and physiological attributes under salt and drought stress. Effective use of silicon in agronomy can be an alternative to the prevalent practice of traditional fertilizers for maintaining sustainable productivity. Therefore, soil nutrition with fertilizers containing plant-available silicon may be considered a cost-effective way to shield plant from various stresses, improve plant growth as well as yield and attain sustainable cultivation worldwide.
Cite this paper: Seal, P. , Das, P. and Biswas, A. (2018) Versatile Potentiality of Silicon in Mitigation of Biotic and Abiotic Stresses in Plants: A Review. American Journal of Plant Sciences, 9, 1433-1454. doi: 10.4236/ajps.2018.97105.

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