Forage Production of annual ryegrass of natural reseeding subjected to nitrogen fertilization in the succession of a soybean crop in crop-livestock integration

O experimento, dividido em duas fases (Fase I e Fase II), teve como objetivo avaliar a produ????o de forragem de azev??m anual (Estanzuela LE 284) de ressemeadura natural na sucess??o da cultura da soja submetido ?? aduba????o nitrogenada em integra????o lavoura-pecu??ria e o efeito residual da aduba????o na produ????o de gr??os de milho (cultura sucessora). Os tratamentos da Fase I constaram de quatro n??veis de aduba????o nitrogenada (ureia 45%) em cobertura (N0 = 0 kg/ha de N, N1 = 22,5 kg/ha de N, N2= 67,5 kg/ha de N e N3 = 135 kg/ha de N) e dois n??veis de aduba????o de base (B1= sem aduba????o; B2= com aduba????o, na ordem de 170 kg/ha da f??rmula 05-25-25). O pasto foi manejado por cortes seguindo um protocolo de altura. A cada vez que o pasto atingia altura m??dia do dossel entre 20-25 cm eram efetuadas duas amostragens (cortes) circulares (0,0881 m??), deixando-se um res??duo de 10-12 cm. Na mesma ocasi??o era coletada uma amostra com um quadro de 0,04 m?? para determina????o do n??mero de perfilhos e ??ndice de ??rea foliar (IAF), sendo coletado todo o perfil do dossel. A Fase II consistiu da avalia????o do efeito residual dos tratamentos de aduba????o da Fase I sobre a produ????o de gr??os de milho. As aduba????es de base (NPK) e de nitrog??nio em cobertura aumentam a produ????o de forragem de azev??m anual de ressemeadura natural em resteva de soja no sistema de integra????o lavoura-pecu??ria. A aduba????o nitrogenada aumenta de forma linear o peso de perfilhos e de l??minas foliares. As m??dias da palhada remanescente de azev??m somadas aos res??duos da cultura da soja atendem a quantidade adequada para a implanta????o da lavoura de ver??o no SPD. A aduba????o nitrogenada n??o apresenta efeito residual sobre a cultura do milho para gr??os em sucess??o.The experiment, divided into two phases (Phase I and Phase II), had as its objective to evaluate forage production of annual ryegrass (Estanzuela LE 284) of natural reseeding subjected to nitrogen fertilization in the succession of a soybean crop in crop-livestock integration and the residual effect of fertilization on the production of corn grains (crop successor). Treatments of Phase I consisted of four levels of nitrogen fertilization (urea 45%) of coverage (N0 = 0 kg/ha de N, N1 = 22,5 kg/ha de N, N2= 67,5 kg/ha de N e N3 = 135 kg/ha de N) and two levels base fertilization (B1= no fertilization; B2= with fertilization in the order of 170 kg/ha of the formula 05-25-25). The pasture was managed by cutes in accordance with its height. Each time the pasture reached the average canopy height from 20-25 cm, two samples (circular cuts - 0,0881 m??) were made leaving a residue of 10-12 cm. During this occasion a sample was collected with a square of 0,04 m?? to determine the number of tillers and leaf area index (LAI). The entire profile of the canopy was cut. Phase II consisted of the evaluation of the residual effect of the fertilization treatments of Phase I on the production of corn grains. The base fertilization (NPK) and the application of nitrogen in coverage, significantly increase forage production of annual ryegrass of natural reseeding in soybean stubble in crop-livestock integration. Nitrogen fertilization linearly increase the weight of tillers and leaf blades. The averages of remaining ryegrass straw added to the soybean crop residues meet the appropriate amount for the implementation of the summer crop in the SPD. Nitrogen fertilization presents no residual effect on the crop yield of corn for grain in succession