Effect of Digestate Application on Herbage Quality and Quantity of Permanent Grassland

Possibilities were studied for using digested substrate as fertiliser applied to grassland. Over 2008-2009, a research trial consisting of four treatments in four replicates (the non-fertilised control; sward fertilized with digested substrates from 100% slurry; 80% slurry and 20% phytomass; 60% slurry and 40% phytomass) was performed on seminatural grassland at Radvaň site. In the sward utilised by three cuts a year, these parameters were studied: botanical composition, dominant species, herbage production, organic matter and mineral substances. At the fertilized treatments, the proportion of grasses was higher in 2009 than in 2008, but that of legumes and other herbs decreased. Dominant grasses were Poa pratensis L., Festuca rubra L., Lolium perenne L., Trisetum flavescens L. while Trifolium repens L. and Medicago falcata L. dominated among legume species. The application of digested substrate as fertiliser showed positive effects on herbage production, the highest increase was found at Treatment 4 where the digested substrate consisting of 60% slurry and 40% phytomass was applied. The highest amounts of crude protein (CP), calcium (Ca) and magnesium (Mg) were recorded at the treatment with the digested substrate composed of 80% slurry and 20% phytomass applied.