Influence of Edaphic Factors and Water Sources on Take-All Root Rot Incidence on Bermudagrass Putting Greens

Take-all root rot (TARR) is a significant disease caused by Gaeumannomyces graminis, Gaeumannomyces sp., Gaeumannomyces graminicola, Candidacolonium cynodontis, and Magnaporthiopsis cynodontis, affecting ultradwarf bermudagrass (UDB) golf course putting greens. The causal agents of TARR, disease management strategies involving manganese fertilization, and chemical treatments for TARR have been well documented. However, turfgrass managers often report inadequate disease control despite proper fungicide applications and maintenance practices. Given this discrepancy, the objective of this study was to investigate the influence of edaphic factors and source water characteristics on TARR incidence. Soil and irrigation water samples were collected from 14 golf courses across the southeastern United States with documented TARR and six golf courses where TARR had not been reported. Locations without TARR exhibited significantly lower concentrations of soil magnesium, manganese, and phosphorus but higher levels of soil potassium. Samples from locations with TARR had lower total organic matter content at a soil depth of 5 to 10 cm compared with those from locations without TARR. No significant differences in nutrient composition or other chemical characteristics were observed in irrigation water samples between locations with and without TARR. This study was the first investigation into the effects of edaphic factors and irrigation water characteristics on TARR incidence on UDB putting greens, and the results could guide related future research.