Effects of Hybrid Bermudagrass Cultivar and Plant Growth Regulator Use On Turf Sustainability and Aesthetics.

The average 18-hole golf course is predominantly comprised of rough areas.  If mowing frequency was reduced using cultivars with inherently slow vertical growth combined with plant growth regulators (PGRs), without compromising aesthetic value, the labor hours, fuel and budget allocated to rough maintenance could be vastly decreased.  The objectives of this research were to determine if bermudagrass (Cynodon spp.) cultivar selection and PGR use can significantly reduce the mowing events required to maintain bermudagrass at golf course rough height without compromising turfgrass aesthetics.  Field research was initiated at Woodruff Farms, Abraham Baldwin Agricultural College, Tifton, GA on April 11, 2011.  Experimental design was a randomized complete split-block design, with three replications.  Factors included year (2011 and 2012), bermudagrass cultivar [improved common types (C. dactylon) as well as hybrid crosses (C. dactylon x C. transvaalensis) and monthly applications of trinexapac-ethyl (TE) compared to a control treatment.  Improved common bermudagrass cultivars included ‘Discovery’ and ‘Celebration’, while hybrids included ‘Patriot’, ‘TifGrand’, ‘Tifway’ and DT-1.  Response variables included August mowing events necessary to maintain the turf between 2.5 to 3.8 cm according to the one-third rule, as well as visual turf quality and color.  Discovery bermudagrass treated with TE required the lowest number of mowing events to maintain the turf between 2.5 and 3.8 cm, followed by Discovery without TE, as well as Celebration, Tifgrand and Tifway treated with TE.  Celebration, Tifgrand and Tifway without TE, as well as Patriot and DT-1 with or without TE required the greatest number of mowing events.  Turf quality of Discovery, Celebration and Patriot bermudagrass was not affected by TE.  Tifgrand treated with TE produced the lowest turf quality, while DT-1 without TE produced the highest turf quality.  Discovery bermudgrass, with and without TE applications resulted in unacceptable turf quality.