Inoculation of corn with diazotrophic bacteria reduces the need for nitrogen fertilization and mitigates environmental contamination risks due to the bacteria's biological nitrogen-fixation capacity. The aim of the present study was to evaluate the effect of corn seed inoculation with Azospirillum brasilense under different nitrogen levels and post-grazing residual heights. The experiment was performed in two growing seasons and conducted in an integrated crop-livestock system for the 2014/15 and 2015/16. A factorial randomized block experimental design with subdivided plots and three factors. The main plots varied in post-grazing residual height (0.10, 0.20, 0.30 m, continuous grazing, or no grazing), the subplots varied in inoculation (with or without seed inoculation), and the sub-subplots varied in nitrogen level (0, 75, 150, 225, or 300 kg ha-1 of N). The higher post-grazing residual height associated an A. brasilense and nitrogen fertilization resulted in increased corn biomass and production and yield. At the 300 kg dose of N, the highest grain yield was obtained under different post-grazing heights (10.15 Mg ha-1) and in the absence of the bacterium (10.00 Mg ha-1). Azospirillum brasilense helps plant growth and yield but does not replace the effect of N fertilization.

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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. . In absolute terms, the winter pasture management of 0.2 m high presented the best results in terms of corn grain productivity.

The overseeding technique allows the establishment of a crop before the harvest of an overseeded crop at the end of the cycle. It aims at making a better use of more favorable seasonal climatic conditions and the intensification of cultivation systems, with the possibility of obtaining another harvest in less time. This work aimed to verify if it is possible to establish the Brassica napus crop in overseeding with the phenological stages at beginning of grain filing (R5) and beginning of soybean physiological maturation (R7) in the Central region of the state of Rio Grande do Sul. The study was performed in a Humid Subtropical climate, in Santa Maria, RS. A randomized block design was used, in a 4 x 2 factorial arrangement with 4 replications, with four seed Brassica napus densities (3, 6, 12, and 18 kg ha-1) and two developmental stages of the soybean crop (R5 and R7), in addition to the control treatment sown in rows directly on the straw right after soybean harvest (3 kg ha-1- standard). The plant density, yield components, and grain yield were measured. The canola crop is not established when overseeded in the soybean stage R5. The seed density of 6 kg ha-1 achieved the recommended plant density for the canola overseeded in stage R7 of the soybean crop. The 6 kg ha-1 density stood out as the best treatment performed in the R7 stage of the soybean crop.