Development of Safflower Subjected to Nitrogen Rates in Cerrado Soil

摘要

In a context in which the nitrogen fertilizer recommendations in the literature for safflower crop show up conflicting, it was aimed by the present study to evaluate the development of safflower when subjected to nitrogen rates in an Oxisol collected under Cerrado vegetation. The experiment was conducted in a greenhouse using pots filled with Oxisol collected in area under Cerrado vegetation in the layer from 0.0 to 0.20 m. Each experimental unit was represented by a plastic pot of 5 dm-3, the experimental design was completely randomized, consisting of six nitrogen rates (0, 60, 120, 180, 240 and 300 mg°dm-3) and six repetitions. It were assessed plant height, number of leaves, chlorophyll content, number of heads, dry mass of shoot and dry mass of root. The results were submitted to variance analysis and, when significant, to regression analysis, both at 5% probability by SISVAR program. Nitrogen rates positively influence the development of safflower, and the one that best promotes this development is between 160 and 190 mg°dm-3.