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The effect of short-term salt stress induced by carbonate salinization on the indicators of oxidative stress, the activity of antioxidant enzymes, and the content of some metabolites in winter triticale seedlings were studied. The experiment was carried out on 7-day-old plants after 12, 24, 48, 72, and 96 h of exposure to 120 mM sodium carbonate solution. The content of malonic dialdehyde, hydrogen peroxide, and the activity of enzymes (catalase, guaiacol peroxidase, and ascorbate peroxidase) were determined. It was shown that carbonate salinization causes significant changes in all mentioned parameters. Thus, more than a threefold increase in the content of hydrogen peroxide was noted in triticale shoots already after 12 h of the experiment. Intensified lipid peroxidation was also observed in the shoots during the first days of salinization. Less significant increase in both indicators was recorded in the roots. An increased activity of the studied enzymes (ascorbate peroxidase, guaiacol peroxidase, and catalase) was noted in the shoots. The analysis of the results showed that the specificity of carbonate salinization can be attributed to more intense accumulation of hydrogen peroxide in the shoots compared with the roots and a decrease in MDA content in triticale shoots by 48 h of exposure.

Study of the functional state of the photosynthetic apparatus in winter triticale under conditions of salinity (120 mM NaCl) has been carried out. It is shown that the initial stress response (up to 24–48 hours) is characterized by a 35% reduction in stomatal conductance, an increase in the RuBisCo activity (up to 37 μmol NADH/min g), and a high rate of electron transport (up to 502 μmol DCPIP/mg Chl h). The response of plants after 48 hours of salinity is associated with a significant increase in stomatal conductance (up to 68.3 nmol/m2 s), as well as the decline in rate of electron transport (up to 222 μmol DCPIP/mg Chl h), the RuBisCo activity (up to 22 μmol NADH/min g), and the rate of photosynthesis (up to 10.96 μmol CO2/m2 s). In addition, plants preserve their functional photosynthetic apparatus under conditions of continuous salinity (lasting for more than 48 h) reducing the efficiency of photosynthesis.

The characteristics of development of oxidative stress and change in activity of antioxidant enzymes in winter triticale shoots and roots under the effect of 120 mM NaCl are investigated. It is shown that the salinity stress response of plants has a diphasic character. The stress response phase (12–24 h) is characterized by a 2.5-fold increase in the amount of hydrogen peroxide and, accordingly, in the intensity of lipid peroxidation, diagnosed by the increase in the amount of malondialdehyde by 2–3 times in the plant shoots and roots. Both the H2O2 level and intensity of oxidative processes stabilized in the next phase of specific adaptation (24–96 h). A general tendency of a change in the activity of guaiacol peroxidase and catalase, enzymes decomposing hydrogen peroxide in roots and shoots, is not found.

The accumulation of nickel ions in the roots and shoots of vetch seedlings (Vicia sativa L.) at increasing concentrations of nickel chloride in the medium was studied. It was shown that the accumulation of nickel in the shoots was increased when the concentration of nickel chloride in the medium was more than 50 μM. The bioconcentration factor and sustainability index for vetch seedlings were calculated under the experimental conditions. The obtained results were similar to parameters for other plants, grown on a nutrient medium or soil substrate. First, the obtained results allowed estimate the limits of nickel chloride concentrations for four of five zones, which correspond to the theoretical concept of dose–response curves in the studies on the influence of physiologically essential heavy metals on plants (Prasad 2010). Some parameters of oxidative stress caused by the presence of nickel chloride in the medium were shown. It seems that at low nickel concentrations in the medium in vetch seedlings the increase of several biochemical parameters (catalase activity and proline) caused by the high amylase activity in seeds.