Evaluation of organic amendments to enhance dollar spot (Sclerotinia homoeocarpa) suppression on creeping bentgrass fairways
Cody Beckley: University of Maryland
<div>There is increasing interest in the use of alternative methods to standard fungicide programs for the control of dollar spot (<em>Sclerotinia homoeocarpa</em> F.T. Bennett) of turfgrass. Organic amendments, including composts and compost extracts, are one option that warrant additional examination. A 2-yr trial was initiated in late 2016 on creeping bentgrass (<em>Agrostis stolonifera</em> L.) maintained as a golf course fairway to evaluate various composts for dollar spot control when combined with fungicides. Main plot factor consisted of a municipal waste compost applied at establishment or as a bi-annual topdressing, a biochar applied at establishment or as a bi-annual topdressing, a standard fertility treatment, a standard fertility treatment + vermicompost extract program, or none. Sub-plot factor consisted of fungicides (contact 14 d, penetrant 14 d, contact threshold, penetrant threshold, or none). Threshold fungicide treatments were applied once two of four replicates exhibited > 2 infection centers per plot. Fertility levels within all main plots were normalized over the trial period. In 2017, all fertility treatments significantly reduced dollar spot incidence compared to none on three of six individual rating dates. An ongoing analysis of nutrient content in leaf tissue and of soil microbes will aid our understanding of nutrient availability in addition to non-nutritional effects composts have on dollar spot development.</div>
View Presentation |
