An Examination of Biostimulant Properties of Commonly Available Soil Amendments on Fresh and Sterile Soil.

Many turf managers are faced with increasing pressure to reduce water and fertilizer inputs, while simultaneously maintaining acceptable turf quality and playability.   Soil amendment and biostimulant products are being introduced to maximize the limited water and fertilizer inputs. The purpose of this experiment was to evaluate plant and soil response to three biostimulants under sterile and non-sterile soil conditions. Three biostimulants were provided by Aquatrols Corporation and included a soil surfactant (ACA1848), an amino acid biostimulant product (ACA2786) and a bovine fecal slurry (ACA3255). To test the effect of biostimulation, turf biomass production, percent cover, soil water percolation rates, soil microbial biomass, arbuscular mycorrhizal association and sacrificed plant biomass production were analyzed. The parameters were measured in L. perenne (Perennial Ryegrass) grown in a sterile and non-sterile native silt loam under growth chamber conditions. None of the products exhibited significant effects in turf grown in the sterile soil. However, all three products exhibited significant biostimulant effects in the non-sterilized soil by increasing total turf biomass compared to the non-sterile control. There were significant treatment and treatment as a function of time interactions observed in the L. perenne clippings weight grown in non-sterile soil compare to the non-sterile control, suggesting the soil microbial community mediated plant responses to treatment in the non-sterile soil.