Global Maize Project in Brazil: Itiquira, Mato Grosso

Cropping system intensification will be necessary to meet the future demands for corn (maize). The established system 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 was established to identify gaps in yield between current technology and improved technology aimed at achieving EI.

This experiment was initiated in November 2009 at Itiquira, Mato Grosso. This is an Oxisol site that has been under cultivation for 20 years. The experiment has a split-plot design with the main plots involving three types of cultivation systems and the sub plots being three levels of N input plus a control. The levels of cultivation are: 1) farmer practice (FP) of soybean followed by corn; 2) FP + a forage crop (Brachiaria decumbens) in the winter; and 3) EI involving a 3-year complete crop rotation cycle of soybean, corn (second crop), forage, soybean, crotalaria, regular corn, and forage. The EI treatment will occur three times, alternating the initiation point of the crop rotation to permit the production of corn every summer. The levels of N input are 50, 100, and 150 kg N/ha for the first corn crop (summer crop) or 30, 60, and 90 kg N/ha for the second corn crop, plus a control with no N added in both cases.

The results for 2009/2010 (first experiment year) have clearly demonstrated that: 1) there was a good response to N in either corn crop, which positively influenced yields and total N uptake, and 2) the addition of N positively impacted the dry-matter yield of the forage grass cultivated with corn.

This is a long-term project intended to influence current opinions on how to best manage cereal production in the region. More results should be available soon for the winter and summer crops. IPNI-18