Global Maize Project in Brazil: Itiquira, Mato Grosso

IPNI-2009-BRA-GM18

29 Apr 2016

2015 Annual Interpretive Summary


Cropping system intensification will be necessary to meet the future demand for corn (maize). Ecological Intensification (EI) seeks cereal production systems that satisfy future demands while developing cultivation practices with minimum interference to the surrounding environment. A Global Maize Project (GMP) site was established to identify gaps in yield between current technology and improved technology aimed at achieving EI. The experiment was initiated in November 2009 at Itiquira, Mato Grosso on an Oxisol that has been under cultivation for 20 years. The experiment has a split-plot design with main plots involving three types of cultivation systems, and the sub plots being three levels of N input plus a control. The types of cultivation being evaluated are: farmer practice (FP) of soybean followed by corn; FP + a forage crop (Brachiaria decumbens) in the winter; and EI involving a 3-year complete crop rotation cycle of soybean, corn (second crop), forage, soybean, crotalaria, regular corn, and forage. The EI treatment occurs three times, alternating the initiation point of the crop rotation to permit the production of corn every summer. The application rates of N fertilizer were 70, 140, and 210 kg N/ha for the first corn crop (summer crop) or 40, 80, and 120 kg N/ha for the second corn crop, plus a control with no N added in both cases.

The results from last season indicate exponential responses to N in both maize crops, which positively influenced maize yields. The addition of N positively impacted the dry matter yield of the forage grass associated with corn. The EI treatment had a negative impact on maize second crop yield as compared to the farmer's treatment, which may be caused by excessive biomass produced by the brachiaria grass causing N immobilization over the next season.

Some changes in the project are under evaluation in order to promote a better development of crops under EI. This is a long-term project intended to influence current opinions on how to best manage cereal production in the region.