Comparative analysis of the photosynthetic potential of new spring barley varieties in the arid climate zone of the Lower Volga region

   Since the climatic conditions have become more arid in the Southern Federal District over the past thirty years, spring barley productivity has sharply reduced. According to the early research and data on meteorological forecasts, in 2022–2023 in the Gorodishchensky district of the Volgograd region there was established an experimental plot based on the Federal Research Center of Agroecology of RAS to test such spring barley varieties as ‘Medikum 139’ (standard, FRC of Agroecology of RAS), ‘Ratnik’, ‘Fedos’, ‘Format’, ‘Azimuth’ ‘Shchedry’, ‘Leon’ (FSBRI “ARC “Donskoy”). These varieties were selected based on their characteristics as the most resistant to abiotic stress factors of the environment. All records and observations were carried out according to generally accepted methods. During the vegetation period, there were carried out observations and there were taken samples to study photosynthetic indicators in the sprouting, tillering, booting, heading stages. There was also carried out leaf diagnostics by the mobile laboratory «Ecotest-2020» to identify the mobility of chloroplasts and nutrients in plants during the tillering period. There was established that the spring barley varieties ‘Azimut’, ‘Format’, ‘Shchedry’ and ‘Leon’ showed the highest adaptability to the acutely arid conditions of the Volgograd region. Based on the analyzed traits of photosynthetic activity, the variety ‘Azimut’ has been included in the State List of Breeding Achievements of the Russian Federation for the Lower Volga region since 2022.