In the extreme climatic conditions of the steppe area of the Saratov region, one of the primary factors in improving alfalfa productivity are the new highly productive and adaptive varieties. The purpose of the current study was to identify the most promising populations according to feed productivity for the development of new highly productive alfalfa varieties in the conditions of the Trans-Volga area in the Saratov region. The zoned blue alfalfa variety ‘Yuzen’ was used as the standard variety. The variety was included in the State List in 2006 for the Middle Volga and Lower Volga regions. The plot of the Competitive Variety Testing was sown in the spring with the SKS-6-10 seeder in wide rows with a 70 cm of row spacing in six repetitions. The plots were two-row, with an area of 18 m2. Green mass productivity was accounted from the plot (t/ha) in the period ‘bud formation-early bloom’ in the first and subsequent cuttings by hand, in two repetitions per 1 m2 of plot. On average, the amount of productivity of the studied samples was 20.3–23.1 t/ha. The population 6/14 showed the smallest productivity (20.3 t/ha). The largest productivity increase was produced by the populations 7/16, 5/12 and the new variety ‘Virineya’. They exceeded productivity of the standard variety on 1.6–2.2 t/ha. The rest populations also slightly exceeded productivity of the standard variety on 0.2–0.3 t/ha. The maximum productivity of feed units was found in the population 7/16, 1/07 and the variety ‘Virineya’ and it amounted to 4.6–4.9 f.u., t/ha. The minimum one was established in the population 5/08 (4.1 f.u., t/ha). According to crude protein percentage, on average during 2 years of the study, the maximum indicator was shown by the population 5/08, which was on 5.50 more than that of the standard variety.
