Fontes e Épocas de Aplicação de Nitrogênio no Milho Safrinha

Application of nitrogen in different phenological states of the corn crop

“…The highest result with 15.85 grain lines per spike, with nitrogen fertilization in the V0 stage. Gott et al (2014), evaluating the sources and times of application of nitrogen in late summer -early fall corn production, observing that the number of seed lines per spike was not affected by the factors, reaching an average of 15.5 with similar results obtained in the present work with an average of 15.52. In contrast, Kappes et al (2009), worked with corn in late summerearly fall production, in soybean succession, evaluated the performance of the crop in the function of different times of nitrogen application when the plants have three, seven and ten fully expanded leaves and sources of nitrogen (urea, ammonium sulfate and Entec®) in cover, whose results influenced, in terms of time, on the number of seed lines per spike.…”

“…According to Gott et al (2014), evaluating the sources and times of application of nitrogen in late summerearly fall corn, obtained the best results in V10 phenological stage with 6,183.9 kg ha -1 ; however, in this investigation it was found that 7359, 26 kg ha -1 in V5 stage. Ritchie et al (2002), mention that the formation of the total number of grains per corn cob is defined during vegetative V6 and V12 stages.…”

“…(2) Number of seed lines per spike: 10 spikes of each experimental unit were selected and the lines of each spike counted; according to the methodology used by Gott et al (2014).…”

“…(4) Spike height: This was determined in the final cycle of the crop, measuring from the base of the plant until the insertion of the first spike, obtaining the value in cm according to Mar et al (2003). (5) Yield: This was obtained by means of weighing the harvested grains in the selected area, with humidity of 13.0% and the data were expressed in kg ha -1 ; based on the methodology employed by Gott et al (2014).…”

Volatilization of ammonia in stabilized slow-release nitrogen fertilizer under controlled conditions

“…The incorporation of nitrogen fertilizer to the soil may decrease NH 3 volatilization by up to 90% (Ceretta et al, 2002;Ernani et al, 2003). Gott et al (2014) found that by incorporating nitrogen fertilizer to the soil, the losses are lower. However, this practice is not widely used by farmers in nitrogen fertilization, either for lack of adequate equipment for incorporation, for damage that this incorporation can promote in the root system, or by increased application cost.…”