The results of studies by the action of the drug Ecostim on the growth parameters, photosynthetic activity and productivity of Czech winter barley varieties Luran and Lancelot in the conditions of the South of the Republic of Moldova are presented. It has been shown that spraying plants in the tillering phase - the beginning of their emergence into the tube with a growth regulator of a steroid nature - stimulates plant growth, accumulation of plastid pigments in assimilation organs, the formation of raw and absolutely dry biomass and an increase in the yield of varieties. It was shown that the response to processing depends on the varietal characteristics, manifests itself to a greater extent in the Lancelot variety, which is characterized by lower parameters of photosynthetic activity and productivity, compared to the Luran variety.