Global Maize Project in Brazil: Ponta Grossa, Paraná

Cropping system intensification will be necessary to meet the future demands for corn production. The proposed approach of Ecological Intensification (EI) seeks cereal production systems that satisfy these future demands, while developing cultivation practices with minimum interference to the surrounding environment. A Global Maize Project site was established to identify gaps in yield between current technology and improved technology aimed at achieving the goals of EI. The trial was first established at Ponta Grossa, Paraná, in May 2011, by seeding winter crops to respective treatment plots. The soil in the region is an Oxisol that had been under no-till cultivation for six years.

The experiment had a split-plot design with the main plots including three types of management systems and the sub plots having three nitrogen (N) application rates plus an unfertilized control. The different management systems were: (1) farmer practice (FP) involving a 2-year complete crop rotation cycle of black oats, corn, wheat, and soybean; (2) FP + silage production; and (3) EI of forage peas, corn, wheat (changed in 2014), and soybean. The EI treatment is planned to occur twice, alternating the crop rotation initiation point to permit the production of corn every summer. The rates of topdressed N application for maize were 70, 140, and 210 kg N/ha, plus a control with no N added. A 30 kg N/ha in furrow rate was applied to every maize plot.

The results from last season indicated different responses to N, which positively influenced maize yields. Dependent of the crop rotation system a weak response to N was found when forage peas or white oats were part of the rotation, versus a strong response to N when black oat was the winter crop. Maize yield with EI treatment averaged 12.8 t/ha, while FP average yield was 10.4 t/ha. Control (no N) treatment at EI yielded 12.4 t/ha versus 7.9 t/ha for the control at FP. Soybean yield was not affected by the differences in crop rotation and averaged 5.0 t/ha in both systems (EI and FP). This is a long-term project intended to influence current opinions on how to best manage cereal production in the region.