Water regime Poaceae family species in the drought conditions

Abstract

Abstract. The purpose of the research is to consider the patterns of water regime of plants in dry conditions, depending on changes in environmental conditions and plant physiology. The objectives of the research included: identifying abilities of Poaceae family herbs (Festuca pratensis, Bromus inermis L., Agropyron cristatum L., Agropyrum Gaertn.) introduced into crops on the vegetation sites of the lysimetric complex of the Federal Science Center of Agroecology of the Russian Academy of Sciences (Volgograd) to sustainability in adverse environmental conditions. Scientific novelty and practical significance. The study contributes to the solution of issues of effective prediction of the productivity of forage grasses, since water-regime patterns of growth and development of vegetation must be taken into account when developing optimal growing methods. Methods. The determination of the water-holding capacity of herbs was carried out according to the Arlanda method and is based on taking into account the water loss by plants. The intensity of transpiration was determined by the method of fast weighing the selected sheet of L. А. Ivanov. A description of the mechanism of water retention by plants with an increase in drought is given. Results. As a result, it has been established that perennial grasses of the family Poaceae have a high potential for resistance to soil and atmospheric drought. The largest water retention capacity is: Bromus inermis L. (87.8%), Agropyrum Gaertn. (87.1 %) and Agropyron cristatum L. (87.0 %). The ability to change water retention capacity can be viewed not only as an adaptive function in changing environmental conditions, but also as a dynamic process that characterizes the natural course of the metabolism of cells and tissues during ontogenesis. Indicators of transpiration intensity in species of the Poaceae family usually reach a maximum up to high midday temperatures. The highest rates were found in Bromus inermis L. and Agropyrum Gaertn., for which in the morning they reached 1.41–1.42 g/dm2-h.