DROUGHT EFFECTS ON MINERAL COMPOSITION OF THE LEAVES AND SEEDS OF AMARANTHUS TRICOLOR AND AMARANTHUS CRUENTUS

In global climate change, drought stress is one of the environmental restraining factors that can significantly influence the growth and development of crop plants. Drought stress conditions can also cause undesirable changes in plant physiological and metabolic processes. The influence of soil drought on the mineral composition of leaves and seeds of two species of amaranth (Amaranthus tricolor L. and Amaranthus cruentus L.) with С4-type of photosynthesis was studied through energy dispersive spectrometry (ESD). The recent investigations were carried out during the years 2020–2022 at the Department of Genofonde and Bioresources of Plants, Federal Scientific Center for Horticulture, Moscow, Russia. The research results showed the leaves of both amaranth with major elements, i.e., K (11.23–15.33), Ca (5.15–7.61), P (3.91–3.92), Mg (2.81–3.36), and Cl (1.86–2.29), whereas, relatively lower values were recorded for Fe (0.05–0.48), and Na (0.07–0.11) mass% respectively. Regarding amaranth plants seed composition, the major elements were K (13.86–13.97), P (7.02–9.76), Mg (3.78–5.64), Ca (3.31–4.78), Cl (2.81–5.30), and Mo (2.80–2.86) mass% respectively. In the species, A. tricolor, a strong correlation was observed between the elements, i.e., S-Cu, Mg-Si, Na-Cu, Na-S, Na-Ca, Na-Si, and Si-S in leaves, while in seeds, these were between Ca-Cu, Mg-Cl, Si-Mn, Ca-Mo, and Cl-Mn. In the other species of amaranth, A. cruentus, the elements viz., Mg-S, Mg-Mo, S-Mo, Mg-Cl, S-Cl, Cl-Mo, Cl-P, P-S, Si-Cl, Ca-Mo, S-Ca, Mg-Ca, Mg-P, P-Mo, and Mg-Si in leaves, while Ni-Cu, Mg-P, Si-P, and Si-Cl in seeds also showed strong relationship. Effects of drought led to a weakening of these ties and the formation of new ones. The accumulation of mineral elements in the leaves of amaranth plants varies from species to species under drought conditions, and A. tricolor cv. Valentina was found most resistant to drought conditions.