Relative Resistance of Creeping Bentgrass Cultivars to Sclerotinia homoeocarpa and Typhula incarnata

Numerous creeping bentgrass ( Agrostis stolonifera L.) cultivars with improved characteristics have been released in the past decade. Some, such as ‘Declaration’ and ‘Memorial,’ have shown resistance to Sclerotinia homoeocarpa F.T. Bennett (the causal agent of dollar spot) in university research trials. Resistance of eight bentgrass cultivars to S. homoeocarpa and Typhula incarnata Lasch were compared to ‘Penncross’ in Wisconsin from 2009‐2012, and their potential ability to significantly reduce fungicide usage was examined. Of the eight cultivars tested, only Declaration and Memorial consistently exhibited partial resistance to both S. homoeocarpa and T. incarnata relative to Penncross over the length of the study. Disease development on the remaining cultivars varied with year and no clear trends were observed. Despite exhibiting partial resistance, a substantial amount of both diseases developed on all eight cultivars in all three years. Renovating to a resistant cultivar may reduce, but not eliminate, the need for fungicide applications to effectively manage dollar spot and Typhula blight.