Antioxidant status of barley seedlings under conditions of excess manganese

The system of protection against the effects of heavy metals (TM) can differ not only in different species of plants, but also in different varieties. Manganese (Mn), as a biogenic element, is necessary for normal plant growth and development. However, in the case of concentrations exceeding the optimal level, it negatively affects both linear plant growth and physiological processes. The paper presents data on the assessment of the effect of excess manganese (II) ions (30, 60 and 90 mg/l of active substance) on barley seedlings of different varieties. Resistance of plants to ionic toxicity of manganese (II) was judged by the value of antioxidant activity (AOA) of superoxide dismutase (SOD), the content of low-molecular antioxidants (chlorophyll a and b, carotenoids and anthocyanins) in barley leaves. For most of the varieties studied, an increase in AOA of SOD, the content of anthocyanins indicating the activation of plant protective mechanisms, was noted. The amount of green pigments, as well as carotenoids, on the contrary, decreased, compared with the control, which indicated a violation of the processes of photosynthesis in them.