Soil correction, growth, and nutrition of Panicum maximum in response to rates and methods of application of steel slag and limestone

The main objective of this study was to evaluate the effectiveness of a soil conditioner derived from steel slag (Agrosilicio Plus – ASP) compared to dolomitic limestone (DLS) in agriculture. The research questions were about how ASP compares to DLS in terms of soil acidity correction, productivity, and the nutritional status of the forage grass Panicum maximum cv. BRS Zuri. Two experiments were conducted in a greenhouse using plastic pots filled with a 0-20 cm layer of Ferrasol. In the first experiment, soil conditioners were applied on the surface, while in the second, they were incorporated into the soil. A complete block design with a 2 × 4 + 1 factorial arrangement was employed. The factors included two soil conditioners (ASP and DLS) at four application rates (25%, 50%, 100%, and 150% of the liming requirement). A control treatment without any conditioner application was also included. P. maximum was grown in three successive 45-day cropping cycles. The shoot dry mass and nutrient content in plants’ tissues were measured. Both ASP and DLS were effective in correcting soil acidity. The ASP led to a higher silicon accumulation in the plants, whereas DLS resulted in higher calcium accumulation. Increasing rates of both conditioners generally had positive effects on most variables measured. When applied on the surface, ASP led to higher dry mass production accumulated in three crops. ASP is a viable alternative to limestone for correcting soil acidity and supplying essential nutrients and silicon to BRS Zuri grass. Additionally, ASP can effectively be applied on the soil surface.