The article reflects the results of five-year researches in the conditions of light chestnut soils of the Volgograd region to study the ways to increase photosynthetic indicators and yield of Sudan grass of the Allegory variety green mass through the use of mineral fertilizers and pre-sowing seed treatment. The experiment scheme included the following options: 1. Control variant without fertilizers; 2. N120P120K90 +N30; 3.Raykat Start; 4. N120P120K90 +N30+Raikat Start + N30. The seeding rate was 3.0 million of viable seeds per hectare. For all the mineral fertilizers application variants, the dynamics of the increase in the leaf surface area and photosynthetic material was noted. The study of the different nutrition levels influence on the Sudan grass green mass productivity showed the advantage of the option with the combined use of the Raikat Start growth stimulator and mineral fertilizers, this allows to get the increase in comparison with the control variant in the amount of 26 t/ha for three mowings. The application of mineral fertilizers provided the increase of 17.5 t/ha. According to the variant with using only Raikat Start, the increase was 7.4 t/ha.