FORAGE TALL FESCUE SEED YIELDS ENHANCED BY PLANT GROWTH REGULATORS

M.P. Rolston¹; W. J. Archie¹ and B.L. McCloy^2
1AgResearch Ltd, PO Box 60, Lincoln, New Zealand
²NZ Arable Ltd, PO Box 16-101, Christchurch, New Zealand

The plant growth regulator (PGR) trinexapac-ethyl was evaluated over four years in seven field trials with forage tall fescue (Festuca arundinacea syn. Schedonorus). Average seed yield increase from 200 and 300 g ai (active ingredient) ha^-1 were 58 and 64% respectively. The 200 g ha^-1 treatment was significant (P<0.05) in six out of seven trials, while the 300 g ai treatment was significant in all trials. On average the 300 g ha^-1 rate was not significantly different from 200 g ha^-1. The responses were associated with a marked decrease in lodging and with stem shortening. Crop bulk at harvest was not reduced. A survey of 40 tall fescue seed growers two years after the introduction, found 100% adoption of the PGR trinexapac-ethyl.