Trinexapac‐ethyl applications and lightweight rolling on ultradwarf bermudagrass putting greens

Abstract

Plant growth regulator (PGR) applications are a common practice in managing ultradwarf bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt‐Davy] putting greens. Trinexapac‐ethyl (TE) is a frequently used PGR to reduce the rapid shoot growth that could reduce ball roll distance (BRD) and increase turfgrass quality. Lightweight rolling (LWR) of putting greens is a practice implemented to sustain or increase BRD. The objective of this research was to determine effects of weekly TE applications and LWR on the BRD and turfgrass quality of an ultradwarf bermudagrass putting green. Experiments were conducted in Knoxville, TN, and Starkville, MS, on a ‘MiniVerde’ ultradwarf bermudagrass putting green. Trinexapac‐ethyl treatments included 0, 0.008, 0.024, or 0.072 lb a.i. acre−1 wk−1 and LWR five times per week. Ball roll distance was measured with a Pelzmeter in 2016 and a Stimpmeter in 2017. Turfgrass quality was visually assessed at both locations on a 1 to 9 scale, with ratings of ≥ 6 being acceptable. At both locations, the BRDs of plots treated with 0.024 lb TE acre−1 wk−1 with LWR were only 5 inch less than 0.072 lb TE acre−1 wk−1 without LWR, a difference that is likely to be imperceptible to golfers. In addition, TE applied at 0.024 lb a.i. acre−1 wk−1 consistently yielded greater turfgrass quality than 0.072 lb TE acre−1 wk−1. Implementing LWR practices with TE application rates at 0.024 lb acre−1 wk−1 can provide similar BRD and increased turfgrass quality as TE applied at 0.072 lb acre−1 wk−1 without LWR.

Evaluation of Fall and Winter Trinexapac-ethyl Applications on Ultradwarf Bermudagrass Putting Green Color, Quality, and Green Cover

“…TE is a type II, class A, late-stage gibberellic acid inhibitor (Rademacher 2015). Turfgrass color, quality, rooting, shade tolerance, photosynthesis, and drought tolerance improved after applications of TE (Ervin and Koski 1998;Fry and Huang 2004;Qian and Engelke 1999;Rademacher 2015;Reasor and Brosnan 2020). TE is also reported to bolster certain plant stress defenses such as traffic tolerance and salt tolerance (Sattar et al 2019;Williams et al 2010).…”