Influence of dolomite flour on fodder productivity of biennial melilot
The effect of dolomite flour on the productivity of melilot was studied in 2019-2020 on leached chernozem with neutral acid reaction (pH(KCl) = 5.4) of the soil medium. The study objects were Melilotus hirsutus of Solnyshko variety and Melilotus albus of Almaz variety. In a two-factor field experiment, we studied the effect of mineral fertilizers (factor A) and dolomite flour dose (factor B). Factor A had two gradations: without fertilizers (control) and with the application of P60K60. Factor B had four gradations: without application (0), calculated by1.0 hydrolytic acidity (1.0 Hh - 7.6 t/ha), 1.5 hydrolytic acidity (1.5 Hh - 11.4 t/ha), and 2.0 hydrolytic acidity (2.0 Hh - 15.2 t/ha). The seeding rate was 7 million viable seeds per hectare; the seeds were sown by the row method (0.3 m). The most developed photosynthetic apparatus of both melilot species was noted in the option with the introduction of dolomite flour at the dose of 2 Hh against the background of P60K60. Application of mineral fertilizers increased the dry matter yield of Melilotus hirsutus by 8.0-13.3%; the dry matter yield of Melilotus albus increased by 4.5-8.8%. The use of dolomite flour increased the dry matter yield of Melilotus hirsutus by 11.2-29.9%; the dry matter yield of Melilotus albus increased by 9.6-28.5%; an efficiency increase was noted at the maximum dose in the experiment. The use of mineral fertilizers and dolomite flour increased the nutritional value of fodders. The highest productivity of 1 hectare of Melilotus hirsutus crops was observed when P60K60 and dolomite flour were applied by 2.0 Hh - 8.99 thousand fodder units, 3.05 tons of digestible protein, 109.8 GJ of metabolic energy; for Melilotus albus in the same option, the values were 9.47 thousand fodder units, 3.08 t, and 116.4 GJ, respectively.