IMPACT OF CUT GRASS OF LAWN CULTIVARS L. PERENNE ON INITIAL GROWTH OF OTHER GRASS SPECIES

摘要

Lawns are an important element of the public space. Their aesthetic and functional values as well as durability are determined by cultivation treatments, in particular mowing (from several to several ten times in the growing season). Cut biomass is usually collected and removed from the surface of lawns, but sometimes it is deliberately left on the lawn surface, thereby influencing the growth and development of plants. The aim of the study was to assess the effect of mown aboveground biomass of 3 lawn cultivars of perennial ryegrass (L. perenne) (commonly used in lawn blends) on the initial growth of other cultivars of lawn grasses. The investigations were conducted in the laboratory in Petri dishes for analysis of aqueous leaf extracts, and in specially prepared glass pots, in which the seeds of the acceptors were covered with fresh aboveground biomass of L. perenne. The control consisted of objects with filter paper wetted with distilled water or objects without donor leaves on the substrate.The investigations demonstrated that both the aqueous leaf extracts and the cut vegetative aboveground shoots of the lawn grass cultivars (donors) placed on a sandy substrate exerted a significant effect on the initial growth of the tested acceptors by impeding plant emergence to the greatest extent and limiting the length of roots and the height of seedlings to a lesser extent. This effect may be related to the allelopathic properties of Lp, which is additionally confirmed by the content of flavonoids and phenolic acids (also identified in the sand culture with the cut donor biomass) i.e. allelopathic compounds, in its leaves. Therefore, mown L. perenne grass should not be left on the lawn surface, since it has an adverse effect on the growth of other lawn grass cultivars.