INFLUENCE OF BIOGENIC ELEMENTS (Ca, Mg) THE CATALASE ACTIVITY IN THE YOUNG SHOOTS AND LEAVES OF TEA PLANT (<i>CAMELLIA SINENSIS</i> (L.) KUNTZE)
To assess the endurance of plants to oxidative stress, a wide range of indicators characterized the functional state of plants is used. As one of the most informative indicators, along with other enzymes (peroxidase, superoxide dismutase, etc.), catalase is considered. The aim of this work was to study the effect of root application of calcium and magnesium-containing substances on the activity of catalase in the leaves of a tea plant. In the humid subtropical zone of Russia on tea plantations under the conditions of a field experiment with fertilizers, the activity of the antioxidant enzyme catalase in young shoots and mature leaves of Kolhida tea was studied. The dynamics of the concentration of cell sap of young shoots and the catalase activity of tea plant leaves during different periods of vegetation, including those covering drought in combination with short-term hyperthermia due to day dynamics, is shown. It was found that an increase in the concentration of cell sap of young shoots under stressful conditions was accompanied by an increase in the activity of mature leaf catalase (r = 0.60) and inhibition of catalase activity in young shoots (r = -0.59). The effect of the root use of calcium in the form of a natural substance (100 kg / ha CaO) and magnesium in the form of MgSO<sub>4</sub> (60 kg / ha Mg) on the activity of the antioxidant enzyme catalase in young shoots and mature tea leaves was studied. It is shown (in comparison with the control) an increase in the activity of catalase in mature leaves in certain periods against the background of the use of calcium-containing natural material. The use of magnesium-containing fertilizers reduced the resistance of plants to stress, which was recorded by a significant increase in the concentration of cell sap in young shoots and lower catalase activity in young and mature leaves.