Response of six dwarf-type bermudagrasses to trinexapac-ethyl

Abstract

Trinexapac-ethyl (TE) is an effective plant growth retardant for hybrid bermudagrass; however, growth responses of various dwarf-type bermudagrass cultivars to TE have not been reported. Two 60-day greenhouse experiments were conducted at the Clemson Greenhouse Research Complex, Clemson, S.C., to evaluate the response of 'Champion', 'FloraDwarf', 'MiniVerde', 'MS Supreme', 'Tifdwarf, and 'TifEagle' bermudagrass with and without TE at 0.0125 kg·ha -1 a.i. per 10 days. From 20 to 60 days after initial treatments, TE enhanced visual quality 9% to 13% for all cultivars. From four samples, TE reduced clippings 63%, 63%, 69%, 62%, 64%, and 46% for 'Champion', 'FloraDwarf, 'MiniVerde', 'Tifdwarf', and 'TifEagle', respectively. Trinexapac-ethyl enhanced root mass 23% and 27% for 'MiniVerde' and 'FloraDwarf' bermudagrass, respectively. 'Champion', 'MS Supreme', 'Tifdwarf', and 'TifEagle' bermudagrass treated with TE had similar root mass to the untreated respective cultivars. Among untreated cultivars, 'FloraDwarf', 'MiniVerde', 'MS Supreme', and 'Tifdwarf' had similar root masses; however compared to these cultivars, 'Champion' and 'TifEagle' had 33% and 81% less root mass, respectively. Root length was unaffected by TE; however, 'Champion' and 'TifEagle' averaged 20% and 36% less root length compared to 'Tifdwarf' bermudagrass, respectively, while 'FloraDwarf', 'MiniVerde', and 'MS Supreme' had similar root length to 'Tifdwarf'. Trinesapac-ethyl safely enhanced turf quality and reduced clipping yield at 0.0125 kg·ha-1 per 10 days without inhibiting root growth of six dwarf-type bermudagrasses. Chemical name used: [4-(cyclopropyl-[α]-hydroxymethylene)-3,5-dioso-cyclohesane carboxylic acid ethyl ester] (trinexapac-ethyl).