Role of beneficial elements in plants: implications for the photosynthetic process

Essential macro- and microelements availability strictly influences photosynthetic process as well as the overall plant status. Besides essential macro- and micronutrients, a group of other elements described as 'beneficial' has been proposed to ameliorate plant performances under optimal and/or stressful conditions. The first explanation of the term 'essential', as suggested by Arnon and Stout in 1939, defined beneficial elements as not essentials since they are not necessary for plants to complete their life cycle. However, at low amounts, they can exert promoting effects on plant performances, including photosynthesis. In this review, we summarize the positive effect of seven beneficial elements (Se, Si, Na, I, Ti, Ce, and La) on plant photosynthetic processes to depict a clear picture of the influences of these beneficial elements on photosynthesis.