Plantabilidade de milho na resteva de azevém cobertura e pastejado no sistema integração lavoura-pecuária, dessecados em diferentes épocas

Abstract

The crop-livestock integration is being a very interesting alternative to diversify income of ownership and maximize the use of land, but when used wrongly can compromise the system of agricultural production, mainly due to compression resulting from the action of the hooves of the animals on the soil surface. Similarly, the ryegrass used only for cover can affect plantability of the successor crop when desiccated without planning. This study aimed to evaluate the plantability of maize stubble of ryegrass grazed and not grazed (cover), in function of different periods of desiccation and stoppage of grazing in the crop-livestock system. There were two experiments, grazed ryegrass in the continuous method of variable stocking rate, keeping the canopy height of 20 cm and plant ryegrass cover, where the only management was the desiccation. The experiments were conducted in a completely randomized block design with four replications, where the treatments were composed for the time intervals between the desiccation/removal of animals and corn seeding (30, 15, 0 days before seeding). In the seeding of maize was used a tillage seeder equipped with furrow opener of fertilizer of the type double disc. Was evaluated the amount of straw at planting time, the soil density, the depth of planting, the emergence rate index, the average uniformity of distribution of emerged plants and the initial stand of corn. The different times of desiccation influenced significantly for all variables analyzed considering the two experiments, being that in the cover ryegrass only the density of the soil was homogeneous between the treatments, while for ryegrass used only for animal grazing the amount of straw at planting time didn’t show statistical difference.