Resistance to water deficit of transgenic winter wheat plants of the T3 seed generation with overexpression of the ornithine-Δ-aminotransferase gene

Aim. To investigate the resistance to water deficit of transgenic plants of new genotypes of winter soft wheat of the T3 seed generation with overexpression of the proline synthesis gene under physiological and stress conditions. Methods. Genetic transformation by the in planta method, physiological and biochemical, mathematical statistics. Results. In transgenic T3 plants, it was confirmed that the increased activity of the ornithine-δ-aminotransferase enzyme does not significantly affect the content of free proline either under control conditions or under water deficit conditions. It was confirmed that overexpression of the oat gene promotes more active root development in genetically modified plants both under normal and drought conditions: in terms of root length, they exceeded the plants of the original genotypes by 3.9–4.5 cm under normal irrigation, and by 3.3–3.8 cm under drought conditions. Under soil drought conditions, biotechnological plants outperformed the original ones by 14–19 % in terms of grain quantity per plant, and by 10–16 % in terms of grain mass per plant. Conclusions. It was shown that transgenic T3 plants with overexpression of the oat gene are characterized by relatively higher resistance to soil drought conditions than control plants. Activation of growth processes, which is manifested in an increase in stem height and better development of the root system, improves adaptive plasticity and yield of genetically modified plants.