Silicon (Si), a second most abundant element in soil, is nonessential but beneficial for higher plants. Silicon addition can result in improved plant growth, yield and quality.Indeed, application of Si fertilizer is a rather common agricultural practice in many countries and regions, especially in Southeast Asian countries. Despite that numerous research outcomes show the beneficial roles Si plays in providing plants resistance and/or tolerance to various forms of abiotic and biotic stress, convincing evidence is still lacking that Si is involved directly in plant physiological and/or biochemical metabolisms. Since a decade ago rapid progress has been made in developing molecular modes of Si uptake,transport and distribution, molecular mechanisms by which Si provides resistance to stressful environments remain poorly understood. Apart from the beneficial roles Si offers in resistance against stressful environments, Si has been proven to play important roles in biogeochemical cycles of carbon and nutrients and carbon bio-sequestration. In this special issue, we selected five papers contributed by Fan et al. (2018), Han et al. (2018), Li et al. (2018), Yan et al.(2018) and Zhang et al. (2018), respectively, as a window to reflect the latest research progress of this field in China. We hope that through this special issue both basic and applied researches on Si in agriculture can be boosted further both in China and abroad.