In this article violation of the mineral metabolism of plants as a result of secondary contamination with heavy metals (HM), which at high concentrations have a toxic effect on a wide variety of physiological processes, occupies a central place in the problem of the resistance of plant organisms to unfavorable environmental factors. Nanoparticles based on iron, copper and nickel are of considerable interest. The study of the mechanisms of plant adaptation to structurally different nanometals (NM) from the position of changing a number of physiological and biochemical parameters is relevant for a more complete understanding of the adaptive capabilities of organisms in conditions of technogenic nanomaterials. Analysis of the content of photosynthetic pigments allowed the formation of consistent ideas about the selectivity of the effect of nanometals on the components of the pigment system of seedlings, depending both on the composition of the metal and on its concentration. The obtained results serve as additional evidence of the existence of selectivity in the activation of a particular reaction of the plant's antioxidant system, determined by the nature of the nanomaterial. However, a change in the level of ROS in the presence of Ni? and Cu? can be attributed to the non-specific response of plants, since similar changes are characteristic of a variety of stresses of plants and in most cases require further research. In this aspect the main "target" of the action of LF metals was the root system of plants, which determined the interest in identifying mechanisms of phytotoxicity with an emphasis on the study of cell damage in this part of plants.

heavy metals, nanoparticles, tolerance index, photosynthetic pigments, active forms of oxygen, cell viability analysis

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