Effect of Trinexapac-ethyl applied at three rates and two stages on timothy, meadow bromegrass and creeping red fescue seed stands in the Peace River Region of Alberta, Canada.
Yoder, C., Khanal, N., Azooz, R., & Gauthier, T. (2017) Effect of Trinexapac-ethyl applied at three rates and two stages on timothy, meadow bromegrass and creeping red fescue seed stands in the Peace River Region of Alberta, Canada. Poster presented in the IX International Herbage Seed Group Conference held in Pergamino, Argentina on October 31 – November 6, 2017
In Canada, trinexapac-ethyl (TE) plant growth regulator is registered for use only on perennial ryegrass (Lolium perenne L.) for seed production and managing growth of turfgrass on golf courses and commercial sod farms. Three years (2015-2017) of replicated small plot trials were conducted at Beaverlodge, Alberta to determine the effects of TE applied at three rates (200, 300 and 400 g ai/ha) and two growth stages (2-node and early heading) on plant height, lodging, seed yields, seed weight and germination on first year stands of timothy (Phleum pratensis), meadow bromegrass (Bromus biebersteinii) and creeping red fescue (Festuca rubra). Spring topdressing of 35 kg/ha of nitrogen (N) in the form of UAN (28-0-0) was also applied with and without TE at 300 g ai/ha. Precipitation during the growing season at Beaverlodge in 2015 and 2016 was 1.2 and 1.7 times the long term average (30.2 cm). TE reduced plant heights of timothy in both years and reduced lodging in 2016. TE applied at two-node stage increased seed yields by fifty percent in 2015 and thirty percent at both timings in 2016. Plant heights and lodging were reduced by TE on meadow bromegrass in both years but had no effect on seed yield. The application of TE at early heading reduced plant heights of creeping red fescue but did not reduce lodging or improve seed yield. TE had no effect on seed weight or germination on any of the species. Additional N applied with and without TE does not appear to increase seed yields over the same treatments applied alone. It appears TE has potential for use on some grass species grown for seed in Canada.