Evaluation of nitrogen fertilization on the productive performance and nutritional quality of Avena sativaL

Abstract

Forage  requirements  in  Paraguay  have  increased  in  recent  years  due  to  the  growing  number  of  beef  cattle.  During  the  winter months,  lower  production  occurs  due  to  low  temperatures  and  reduced  solar  radiation.  Species  such  as  oats  exhibit  adequate development between April and September, but low yields result from decreased nitrogen (N) availability in the soil. The objective of this study was to evaluate the effect of nitrogen fertilization on oat yield and quality. Application levels of 0, 23, 45,68, 90, and 113 kg N ha?¹ were used in a randomized block design. Forage production, nutritional quality, and nitrogen efficiency were evaluated. The results show that there were no differences in plant height between treatments. However, green forage (25,000 kg  ha?¹) and dry matter (4,000 kg ha?¹) yields were higher with the application of 113 kg N ha?¹. Crude protein concentrations reached 16% with the application of 113 kg N (three times higher than the treatment without application). No differences wereobserved in total digestible nutrients (TDN) or neutral detergent fiber (NDF). Oat nitrogen uptake required 26 kg N per ton of dry matter  produced,  and  the  fertilizer  recovery  efficiency  was  0.4,  with  an  agronomic  efficiency  of  8.3.  In  conclusion,  fertilization with N at a dosage of 150 kg ha-1 improves the yield and quality of oats, therefore, it is an alternative for forage production in the winter period of the eastern region of Paraguay.