Brief History and Introduction to Silicon Research -- Analysis of Silicon in Soil, Plant and Fertilizer -- Silicon Biogeochemistry and Bioavailability in Soil -- Silicon Uptake and Transport in Plants: Physiological and Molecular Aspects -- Silicon-mediated Tolerance to Metals Toxicity -- Silicon-mediated Tolerance to Salt Stress -- Silicon-mediated Tolerance to Drought and Freezing Stress -- Silicon-mediatedTolerance to Other Abiotic Stress -- Silicon and Plant-Pathogen Interactions -- Silicon and Insect pest resistance -- Effect of silicon on crop growth, yield and quality -- Silicon Sources for Agriculture -- Summary and Perspectives.