Mineral composition of oat grains in response to nitrogen fertilization and growth regulator

Nitrogen fertilization (N), in appropriate dose and moment, can favor yield and quality of oat grains. However, its overuse may result in plant lodging, which can be minimized by using growth regulators. With this in mind, this study aimed to evaluate the effect of applying ethyl-trinexapac and nitrogen doses on the accumulation of macro and micronutrients in white oat (IPR Afrodite; Avena sativa L.), grown in different environments in the state of Parana (Londrina and Maua da Serra). The field experimental design used was randomized blocks in split-plots, with four replicates. Treatments consisted of four N doses (0, 30, 60 and 90 kg ha(-1)) and the application or not of growth regulator. The data were subjected to analysis of variance with means comparison by the F test, and regression for the nitrogen doses (p<0.05). For Londrina conditions, applying growth regulator increased the iron content (+29%), and using nitrogen fertilization increased the phosphorus maximum content in the grains when subjected to a 60.65 kg ha(-1) dose. In Maua da Serra, applying growth regulator increased potassium content (+63%), and decreased phosphorus (-20%) and nitrogen (-8%) contents in the grains. The results demonstrate the importance of studies on adequate management practices, aiming to improve the mineral composition of white oat grains.