The effect of stevioside on lipid peroxidation and the parameters of water metabolism of spring wheat, under the conditions of water deficit

Abstract

Aim and Scope: The growth, water exchange parameters, and malondialdehyde content in the leaves of 15 day’s
plants of spring wheat, under the conditions of soil drought and pretreatment with diterpene glycoside stevioside
(10–8 M), were studied in this paper. The cultivar of spring soft wheat (Triticum aestivum L.) Omskaya 33,
included in the State Register of the Western Siberian and the Middle Volga regions, recommended for cultivation
in the Omsk region and in the Republic of Tatarstan of the Russian Federation, as well as the cultivar of spring
soft wheat (T. aestivum L.) Tamoz 2, bred, certified, and widely used in Iraq, was selected as the objects of the
research. Materials and Methods: Experimental design included four options: Control, drought, presowing seed
treatment with stevioside (10–8 M), and under the conditions of drought and sufficiency of water supply for
plants. The moisture content of the soil was 70% in case of normal water supply, and 30% in case of drought. The
determination of length of wheat seedlings showed that leaves of the cultivar Tamoz 2 had a lower height, than
the cultivar Omskaya 33. Result and Discussion: The drought inhibited the growth of plants of two varieties.
Pretreatment with stevioside reduced the effect of drought on the growth of wheat plants of two studied cultivars
of spring wheat. Stevioside increased the water content in conditions of drought only in Omskaya 33, which was
more sensitive to water deficiency. The variety Tamoz 2, in conditions of water deficiency, had less oxidation of
lipids of the plasma membrane, compared to variety Omskaya 33. At the same time, stevioside to a greater extent
reduced the lipid peroxidation (LPO) in the cultivar Omskaya 33, where the processes of LPO under the influence
of a drought were more active. Conclusion: The obtained data may be determined by the antioxidant effect of
stevioside on plants, the mechanism of which has not been identified to date.