Melatonin in Safeguarding Plants from High Light and UV Exposure

Although light is indispensable for plants but when it increases beyond a certain level it can result in damage to the photosynthetic machinery of the plants. An added threat to high light is the presence of UV radiations accompanying high light conditions. Plants have developed many mechanisms for the prevention of the photosynthetic apparatus and maintenance of growth and development under such conditions. An important determinant in this protection process is melatonin. A low molecular weight indoleamine, first identified from animals, is ubiquitously found in plants and is involved in phytoprotection under different adverse environmental conditions. Here we explore the involvement of this molecule in the protection of plants against light stress and establish a possible relationship between the variable luminous conditions and melatonin content in the plants.