Effects of Trinexapac-Ethyl and Lightweight Rolling on Putting Green Performance of Miniverde Hybrid Bermudagrass.

Hybrid bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis] is used on golf course putting greens throughout tropical, subtropical, and temperature climates. Ultradwarf cultivars (e.g., ‘Champion’, ‘MiniVerde’, and ‘TifEagle’) are often selected to maximize putting quality. Plant growth regulators and lightweight rolling are techniques used to increase ball roll distance on ultradwarf bermudagrass putting greens. Research examining season-long effects of these maintenance practices is limited. Research was conducted in 2017 and 2018 to assess the response of ‘MiniVerde’ ultradwarf bermudagrass to weekly applications of trinexapac-ethyl (TE; 0, 8.8, 26.3, or 78.9 g a.i. ha^-1 week^-1) and lightweight rolling (0 or 5 times week^-1). Each year, ball roll distance was measured on forty days from 1 June to 1 September by using a Pelzmeter. Visual turfgrass quality, color, and percent injury were also evaluated. No TE-by-lightweight rolling interactions were detected with lightweight rolling increasing ball roll distances for all rates of TE. Similarly, ball roll distance significantly increased for each TE rate evaluated. However, we did observe significant reductions in turfgrass quality and color with TE applications at 78.9 g ai ha^-1 week^-1 each year, suggesting that rates should not exceed 26.3 g ai ha^-1. Overall, our findings indicate that TE and lightweight rolling increase ball roll distance on ‘MiniVerde’ ultradwarf bermudagrass. However, our work was limited in that TE was re-applied weekly, which may not be optimal for ultradwarf bermudagrass putting greens. Future research should explore optimal TE application regimes for ultradwarf bermudagrass putting greens.