Sulphur as a dynamic mineral element for plants: a review

Purpose Sulphur (S) is one of the essential macroelements in plants. It is considered as the fourth main element after nitrogen, phosphorous and potassium in crop plants. It facilitates growth, development and various physiological processes in plants. The survey of literature reveals that there are no systematic and comprehensive studies on the role of S alone or in combination with other mineral elements and also with plant growth regulators (PGRs) in growth, development, yield, quality and mitigation of abiotic stresses in crop plants. This article, therefore, summarizes the available scattered literature on the above aspects. The present review also highlights S sources, uptake and assimilation, S transporters, S-containing metabolites, S status, storage and redistribution in plants. Methods The available literature published in books, doctorate thesis, scientific research journals, online literature on the relevant aspects was surveyed. The generated idea was drafted in the present manuscript. Results The deficiency of S negatively affects growth phases and productivity of many crop plants. Crop species including oilseeds require S throughout their lifecycle. A variety of sulphate transporters are involved in its uptake, transportation and assimilation. Sulphur plays an important role in the formation of many metabolites and also in the biosynthesis of phytohormone such as ethylene and polyamines, which have diverse roles in physio-biochemical processes of plants. Sulphur has an interaction with other essential macronutrients to enhance the growth and yield of crop plants by improving their uptake, assimilation and remobilization. Moreover, S-containing compounds play an essential role in mitigation of abiotic stresses and provide tolerance to crop plants. Conclusions Sulphur facilitates the performance of plants by improving their growth, photosynthetic, yield and quality parameters. Sulphur fertilization is also found to ameliorate the ill-effect of abiotic stress in plants and improve the productivity of important agricultural crops.