Corn productivity in integrated crop-livestock system: Effect of different forage masses post-grazing

Forage management in integrated crop-livestock system is a complex activity that increases profitability, when well performed, therefore consequently influencing future crop productivity. This study aimed to evaluate the agronomic performance of corn cultivation in the integrated crop-livestock system using the no-tillage system in different forage masses post-grazing. The experiment was conducted in the municipality of Mata, which is located in the state of Rio Grande do Sul, during the agricultural years of 2009/2010, 2010/2011, 2011/2012, 2012/2013 and 2013/2014, under no-till with corn in the summer and black oats plus ryegrass in the winter for grazing. The experimental design was made up of randomized blocks, using four heights of forage mass post-grazing: 0.10, 0.20, 0.30 m conventional grazing and without grazing. For the evaluation of the remaining dry mass of forage, a destructive cut was made at 5 cm from the soil at 28 days after the animals left. The evaluations of plant height, cob insertion height, number of grain rows, number of grains per cob, mass of one-thousand grains, and corn grain yield were performed.  The average values of remaining forage mass were 1.52, 2.26, 2.44, 8.56 and 1.41 Mg ha-1 for the different grazing managements, in which corn productivity were 7.74, 8.82, 7.94, 9.22 and 7.70 Mg ha-1. In absolute terms, the winter pasture management of 0.2 m high presented the best results in terms of corn grain productivity. Key words: Soil coverage, forage, grazing height, income components, zero tillage.