Kapitanska O. Physiological bases of application of a complex of microelements chelated with carboxylic acids for an increasing of a winter wheat photosynthesis efficiency.

The thesis is devoted to the investigation of the physiological bases of the influence of chelated micronutrient compositions created using nanotechnologies, with low doses of application on the photosynthesis efficiency and the grain productivity of modern winter wheat varieties. The treatment of plants with carboxylate of microelements increased the activity of antioxidant enzymes of chloroplasts of the flag leaf of winter wheat with both studied ligands of microelements – succinic and citric acids. The foliar application of plants with microelements chelated with carboxylic acids increased a photosynthetic apparatus activity and the intensity of assimilation of CO2 of the flag leaf of winter wheat. An increase of maximal rate of CO2 uptake under light-saturated conditions, compared with the variant without treatment, in the plants treated of a microelements complex was observed only in conditions of drought. It was established for the first time that the positive effect of plants treatment of complex microelements chelated with carboxylic acids on the quantum efficiency of FS II was more pronounced under a stressful conditions of insufficient moisture supply. The use of a complex of chelated microelements increased the leaf and chlorophyll indexes of canopy, as well as the net productivity of photosynthesis and the radiation use efficiency in crops during the reproductive period of development it is shown. The increase of grain productivity of winter wheat crops in variants with the treatment of plants with microelements chelated with carboxylic acids is due to the optimization of the functioning of the photosynthetic apparatus at various levels of its organization it is established. The use of a complex chelated with carboxylic acids together with nitrogen fertilizers increases the efficiency of the use of nitrogen it has been established. The effect of foliar plant treatment of microelements complex, chelated with carboxylic acids, on the protein content in the grain, was variety-specific, but the gross harvest of protein from a unit of planting area increased regardless of the variety it is shown.