Produtividade, qualidade bromatológica e distinguibilidade de sementes de azevém submetidos a distintos cortes, doses e fontes de nitrogênio

Abstract

The study aimed to evaluate the yield, chemical composition, yield and morphological characterization of seeds of annual ryegrass (Lolium multiflorum Lam) with two nitrogen sources: urea (nitrogen source most widely used and in Brazil, mainly in the south) and ammonium sulfate (source little used by producers, with virtually no loss by volatilization of nitrogen applied dressing), the nitrogen rate of zero, 100, 200, 300 and 400 kg ha- ¹, the agricultural year of 2009. Each treatment received one to three fresh cuts before the deferral for seed production in order to simulate a grazing situation, for ratings of productivity and chemical composition of pasture. The experimental design was randomized blocks. Based on the results did not differ between the sources used for the variables total dry matter, crude protein, acid detergent fiber, neutral detergent fiber, seed yield, number of spikelets per ear, ear length and spikelet number of seeds and length of seeds in three sections. The dose that gave the best response for most of the variables was 400 kg ha-¹ independent of nitrogen source used and the use of pasture with up to three cuts shows no decrease in quality and productivity of the same, but significantly affects the components of seed yield. Based on the variables may be concluded that there was no difference between the applied sources, then the ammonium sulfate had a similar response to urea can then be used as an alternative source of nitrogen.