Trinexapac-Ethyl and Nitrogen Fertilization Rates in Wheat Crop

The objective of this work was to evaluate the effect of trinexapac-ethyl and nitrogen doses on the agronomic performance and grain yield of three wheat cultivars. The experiment was arranged in a randomized block design in a factorial scheme, with three replications. The treatments were two nitrogen fertilization doses (60 and 20 kg ha(-1)), three wheat cultivars (BRS 208, BRS 220, and BRS Guamirim), four trinexapac-ethyl doses (0, 70, 140, and 210 g a.i. ha(-1)) and two harvest years (2008 and 2009). In the Pato Branco microregion, the nitrogen rate of 60 kg ha(-1) was sufficient to maximize the yield potential of the evaluated cultivars. Regardless of the height of the cultivar plants, trinexapac-ethyl showed no positive effect on grain yield, with negative effect under water-deficit stress.