Derivatives of a triazole are used not only as fungicides to prevent infection of plants, but also for treatment. These drugs are actively used against plant diseases caused by basidiomycetes, ascomycetes, and some deuteromycetes. Due to their chemical stability, they have a long-term protective effect, and their solubility in water ensures their movement from the roots to the aerial part of plants. The aim of this work was to study the effect of seed treatment with tebuconazole-containing preparation “Bunker” on the growth of shoots and roots of winter wheat in the light and physiological and biochemical parameters. We used a fungicide of prophylactic and therapeutic action tebuconazole-containing seed treater “Bunker” (August, Russia), the active ingredient of which is tebuconazole (60 g/L). The shoot length and total root length, wet and dry biomass, as well as the content of photosynthetic pigments, reactive oxygen species – hydrogen peroxide (H₂O₂) and lipid peroxidation products (LPO) reacting with thiobarbituric acid (TBA-RP) in the tissues of shoots and roots were analyzed. The content of chlorophylls a and b and carotenoids in the extract was determined spectrophotometrically at wavelengths of 665, 649, and 440 nm, respectively. The obtained results indicate that the action of the drug is aimed at inhibiting the growth of shoots and reducing the ratio of shoot length to root length, while on the 7-9th day of growth, the effectiveness of its action is higher, and the most significant effect is exerted by an increased dose of the disinfectant (1.5 μL/g). It was found statistically significant stimulation of root growth on the 9th day of cultivation, regardless of the dose of the dressing agent. Despite the significant growth-inhibiting effect, treatment with Bunker was not accompanied by activation of oxidative processes in shoot tissues, with the exception of an increase in the content of H₂O₂ and TBA-RP at the initial stage of growth (5 days). In root tissues, the content of H₂O₂ and TBA did not change under the action of the studied preparation. No differences in the content of chlorophylls a and b and carotenoids in the tissues of wheat shoots after treatment with the studied fungicide were found. Based on the data obtained, it can be concluded that seed dressing agents containing tebuconazole as an active ingredient can be used to ensure plant resistance to moisture deficiency and improve mineral nutrition.

Grabelnykh Olga Ivanovna, Doctor of Sciences (Biology), Principal Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation; Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: grolga@sifibr.irk.ru 

Polykova Elizaveta Alekseevna, Leading Engineer, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation; Student, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: polyackova.elizaveta727@mail.ru 

Korsukova Anna Viktorovna, Candidate of Science (Biology), Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation, e-mail: avkorsukova@gmail.com 

Zabanova Natalya Sergeevna, Candidate of Science (Biology), Senior Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation; Assistant Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: pavnatser@mail.ru 

Berezhnaya Ekaterina Vladislavovna, Postgraduate, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation, e-mail: ekaterina809@mail.ru 

Lyubushkina Irina Viktorovna, Candidate of Science (Biology), Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation; Assistant Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: ostrov1873@yandex.ru 

Fedotova Olga Andreevna, Candidate of Science (Biology), Senior Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation, e-mail: ol.borovik@mail.ru 

Stepanov Aleksey Vladimirovich, Candidate of Science (Biology), Senior Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation, e-mail: saw33@list.ru 

Pobezhimova Tamara Pavlovna, Doctor of Sciences (Biology), Principal Research Scientist, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation, e-mail: pobezhimova@sifibr.irk.ru 

Dorofeev Nikolay Vladimirovich, Candidate of Science (Biology), Vice-Director, Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov st., Irkutsk, 664033, Russian Federation, e-mail: nicdoro@gmail.ru

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