Ethephon induced changes in vegetative growth of 'Tifton 85' bermudagrass

The establishment rate of warm-season turf and forage grasses propagated by sprigs or cuttings is of economic importance by determining not only how quickly an area may be utilized but also by influencing the extent of weed invasion. We monitored 'Tifton 85' bermudagrass [Cynodon dactylon (L.) Pers.] vegetative growth response to the application of ethephon (2-chloroethylphosphonic acid), an ethylene-producing compound, and how this treatment affected subsequent vegetative establishment. Responses of established Tifton 85 plants to ethephon treatment when compared with untreated plants included a 22% reduction in plant height, node swelling, bud swelling at the crown, terminal leaf necrosis, chlorotic striping of young developing leaves, and a 118% and 101% increase in leaf/stem fresh and dry weight ratios, respectively. Swelling of ethephon-induced buds appeared to be due to a transient arrest in sprouting. Swelled buds finally sprouted 9 d following ethephon treatment. In glasshouse experiments, vegetative cuttings taken from ethephon treated plants produced 112% more roots under a range of water stress conditions 8 d after cutting removal, and produced 10-fold higher number of tillers at 6 d after planting in soil than untreated cuttings. Tiller production in the soil establishment study was not statistically different between ethephon treated and untreated plants after 21 d. These glasshouse results indicated that it may be feasible to develop ethephon treatments that improve establishment rate and subsequent stand quality of Tifton 85 bermudagrass in field/commercial applications