Influence of trace elements, applied in classical and nano forms, on photosynthesis of higher plants in relation to enhancement of crop productivity

One of the main factors of increasing the productivity of agricultural plants is intensifying the activity of the photo- synthetic apparatus, since the productivity of crops depends on the ability to absorb solar radiation and convert it into the energy of chemical bonds for further use in metabolic processes. The amount of photosynthetically active radia- tion absorbed by crops, in its turn, depends on the area, duration, and activity of the assimilation surface functioning. The use of fertilizers, that contain trace elements, can further achieve both raising the yield of cultivated plants and environmental protection. In this regard, the state-of-the-art research on the infl uence of the main trace elements (iron, zinc, manganese, molybdenum, cobalt, selenium, boron, titanium) and one macroelement - magnesium - on photosynthetic characteristics of plants and crops is discussed. Based on the literature data and the results of our own research, we documented the effect of trace elements on leaves carbon dioxide exchange rates, the content of photo- synthetic pigments, the antioxidant enzymes activity, as well as the traits of the photosynthetic apparatus capacity. The infl uence of nanometals on the content and ratio of pigments, net CO 2 assimilation rate, and the photochemical activity of photosystems, including the effect of stress factors, is discussed. The specifi cities of the infl uence of nanometals are discussed and possible mechanisms of the effect of low concentrations of trace elements on plant metabolism are analyzed. It is shown that trace elements infl uence photosynthetic processes in plants and the systems of their antioxi- dant protection. The relevance of trace elements in the development of new strategies to elaborate the technologies of cultivating next-generation plants, including those that will be based on new physical and chemical properties of macro- and micronutrients in a nano form, is highlighted