EXOGENOUS OPTIMIZATION OF THE ANTIOXIDANT PROTECTION CAPACITY OF PLANTS IN MODERATE DROUGHT CONDITIONS

The effect of Thiourea, Galmet and Thiogalmet on the antioxidant protection capacity of plants in moderate drought conditions was studied. Thiogalmet is a new chemical composition that contains Thiourea (Tu) and Galmet - a preparation that consists of a mixture of potassium, ammonium, magnesium gallates, and potassium molybdate and ammonium paramolybdate. Biological tests were performed in the vegetation complex of the Institute of Genetics, Physiology and Plant Protection. As subjects of investigations served the plants Glycine max (Merr) L Nadejda variety and Zeya mays LP458 cultivar, grown in the Mitcherlih vegetation pots with 40 kg soil and exposed to the drought stress at the critical stages for water. It has been established that pre-treatment of plants with Thiourea, Galmet and, in particular, with Thiogalmet increases the activity of superoxide dismutase (SOD), catalase (CAT), ascorbateperoxidase (APX), glutathione reductase (GLR) and glutathione peroxidase (GLPX). The high activity of antioxidant enzymes is associated with a decrease in the content of malonic di-aldehyde (MDA). The increase in antioxidant protection capacity of plants pre-treated with Thiogalmet was recorded both in optimal conditions and in conditions of oxidative stress induced by drought. Thiogalmet has been shown to be one of the new biologically active chemicals that can be used in agriculture to reduce the negative impact of oxidative stress caused by reactive oxygen species (ROS).