Timing and Frequency Effects of Lightweight Rolling on Dollar Spot Disease in Creeping Bentgrass Putting Greens

Abstract

Dollar spot (DS) (Sclerotinia homoeocarpa F.T. Bennett) is an important disease on golf course turfgrasses in the United States. The objective of this study was to elucidate disease reduction mechanisms related to lightweight rolling. Creeping bentgrass (Agrostis stolonifera L.) plots that were subjected to daily (5 d wk−1) rolling treatments (1x a.m., 1x p.m., 2x a.m.) showed significant DS reductions when compared with a nonrolled control. Treatments rolled in the afternoon (after dew and guttation fluid dissipated) exhibited similar area under disease progress curve (AUDPC) values as treatments rolled in the morning in 2008, 2009, and 2010. Both 1x rolling treatments resulted in significant DS reductions compared with the control in 2009 and 2010. The 2x d−1 treatment exhibited significantly less DS than the control in all years as well as significantly lower AUDPC values than both 1x rolling treatments in 2009 and 2010. Rolling 2x d−1 improved turfgrass quality compared with all other treatments in each year of the study. All rolling treatments exhibited higher root zone volumetric water content (%VWC) compared with the control in 2010, and significant effects on %VWC were observed on individual dates among treatments. Results indicate previously unidentified effects of rolling on putting greens, including added physical and biological effects, which may be contributing to DS suppression.

Effects of Genotype and Isolate on Expression of Dollar Spot in Seashore Paspalum

“…Turfgrass cultural practices, such as proper nitrogen fertility and irrigation, are commonly used to reduce dollar spot symptoms in a turfgrass sward. The removal of guttation fluids with dew whips or the use of lightweight rollers can also reduce disease severity (Giordano et al, 2012). Chemical and biological fungicides are also tools used to manage dollar spot (Walsh et al, 1999).…”

Effects of Rolling and Sand Topdressing on Dollar Spot Severity in Fairway Turfgrass

“…operations (Giordano et al, 2012;Nikolai et al, 2001). Studies have shown that sand textured (80% sand, 10% peat, 10% soil) plots that were rolled had increased percentage of water retention in comparison with the nonrolled plots (Nikolai et al, 2001).…”

“…Studies have shown that sand textured (80% sand, 10% peat, 10% soil) plots that were rolled had increased percentage of water retention in comparison with the nonrolled plots (Nikolai et al, 2001). Therefore, mechanisms by which rolling is suppressive to the dollar spot pathogen could be the effect of soil moisture levels mitigating drought-stress-related disease epidemics (Couch, 1966;Couch and Bloom, 1960;Dykema, 2014), or the effect of beneficial microorganisms that proliferate in the turfgrass edaphic environment, as proposed by Giordano et al (2012). Moreover, our observations support earlier statements that drought-stressed turf is more susceptible to a variety of turf diseases that, in effect, cause a noticeable decrease of turfgrass quality (Couch, 1966;Couch and Bloom, 1960).…”

“…The increasing cost and probable ban of certain chemical pesticides by the U.S. Environmental Protection Agency (2011) are causing turf managers to seek effective yet inexpensive means to control turf diseases. Research on alternative management strategies has given credence to cultural practices that not only promote plant health, but also are antagonistic to the pathogens (Giordano et al, 2012). Primary cultural practices that optimize fertilization, irrigation, and mowing have been shown to decrease dollar spot (Bennett, 1937;Couch 1962Couch , 1966Couch and Bloom, 1960;Endo, 1963;Landschoot and McNitt, 1997;Liu et al, 1995;Markland et al, 1969;Williams et al, 1996).…”

“…Supplementary cultural practices such as sand topdressing effectively reduce dollar spot as well (Skorulski et al, 2010). Perhaps other supplementary cultural practices (cultivation and rolling) could be viable alternatives to chemical pesticide applications, thus decreasing the necessity, extending the efficacy, and reducing possible human exposure to these chemicals (Giordano et al, 2012), so that instead of applying eight to nine fungicide treatments per season at a cost of $16,000 to $27,000 annually on fairways (Turfgrass Producers International, 2011), sand topdressing may alleviate this annual expenditure, and possibly decrease cost per application by 25% to 50%. Although perhaps not as effective as conventional, chemical pest management systems, certain culture practices have proven to be acceptable disease management strategies in terms of playing conditions (Rossi and Grant, 2009).…”