A field experiment was carried out in a Red-Yellow Latosol in 2009 in order to assess the effects of different doses of nitrogen fertilization and water depth and their interaction on the grain yield and quality of wheat BRS 254. The experimental design was a completely randomized block with split plot on water level and four replications. Nitrogen doses in the plot were: 20, 50, 100, 200, and 400 kg ha-1. In the split plot water depths were: 120, 264, 342 and 392 mm. Mean yield and the majority of its components differed significantly with water depth and nitrogen dose. The exception occurred on the number of grains per spikelet which was not affected by nitrogen level. Minimum and maximum yield were 1,135 kg ha-1 and 5,209 kg ha-1, respectively for 120 mm and 50 kg ha-1 of N; and 392 mm and 200 kg ha-1 of N. In all of them, the highest yields were achieved by nitrogen doses over 220 kg ha-1. Crude protein content was significantly affected by water and nitrogen level interaction. The hectoliter mass, the strength of gluten and the falling number were significantly affected by water level. Water depths lower than 365 mm provided hectoliter weight below 78 kg hL-1. On the other hand water depths higher than 340 mm provided falling number below 250 s, suggesting caution on wheat agrossystems water management.
Triticum aestivum; nitrogen fertilization; irrigation
