Photosynthetic potential of spring barley in the conditions of the Lower Volga region

Abstract

Relevance. Increasing grain production requires new ways to increase the yield of grain crops. The study of the interaction of plants depending on the distance from the forest strip is currently of particular relevance. Methods. The scientific article presents the results of the study of spring barley depending on the distance from the forest strips. The purpose of the research was to conduct a comparative analysis of the photosynthetic activity of spring barley crops. The object of research is spring barley Medicum 139. The studies were carried out on the experimental field NVNIISKh, located in the light chestnut subzone of the dry steppe zone of chestnut soils of the Lower Volga. To achieve this goal it was necessary to determine and calculate: the area of the sheet surface; photosynthetic activity of crops; amount of dry phytomass; the net productivity of photosynthesis. Results. Studies have shown that the maximum photosynthetic potential (AF) was reached the phase of “egress into the tube-earing”, when it was 1.5 times higher than in the phase of “tillering-egress into the tube” and “earing-milk ripeness”. The net productivity of photosynthesis (NPF) of spring barley was maximum in the phase of exit to the tube-tillering, minimum in the phase of earing — milk ripeness. The accumulation of dry matter was also observed maximum in the phase of exit to the heading-earing tube, minimal in the phase of heading-milk ripeness. The leaf area affected the formation of the mass of 1000 grains and the number of productive stems in the heading phase: R = 0.5 ... 0.7; R = 0.5 ... 0.6, respectively, depending on the distance from the forest strip. In the phase of milk ripeness a reliable correlation was established between the leaf surface area and the mass of grains in the main ear in 2017, 2018 and 2019 ( R = 0.7, 0.5, 0.6, respectively). The beneficial effect of protective forest stands on soil properties, as well as on the growth, condition and productivity of crops, is noted. The results of the study indicate the important role of forest strips. The scope of development is the soil zone of the Lower Volga.