Global Maize Initiative, Colombia

IPNI-38 Global Maize Initiative, Colombia

Rationale
IPNI has developed the Global Maize Initiative with the idea of promoting the ecological intensification of maize cultivation. Among the selected research locations, an experiment was set up in collaboration with the Federación Nacional de Cultivadores de Cereales y Leguminosas(FENALCE) in Colombia.

Objectives
The specific objectives are: 1) Measure the yield differences among nitrogen management strategies, and 2) Compare the ecological intensification management against traditional maize technology.

Matherials and Methods
The study was planted at the 'Villa Escocia' experimental farm in Buga, Valle del Cauca, Colombia. Located at coordinates: Lat N 3°53'; Long W 76°20' and altitude 960 m. The Buga region has fertile alluvial soils with neutral pH (6.1) and intermediate CEC (16 meq 100 g soil). Organic carbon in the experimental farm soil was evaluated at 1% before the start of the experiment.

The treatments differed only in planting density and the amount and timing of N, and consisted of the following:

T1: Intensive (Eco-intensification) with high plant density (90.000 plants ha^-1) without N in any crop cycle
T2: 90.000 plants ha^-1 with N added 2 out of 3 crop cycles (no N in one of 3 cycles). In the years with N fertilization the nitrogen added was 200 kg ha-1 splitted in three applications at V0, V6 and V10 stages.
T3: 90.000 plants ha^-1 with N added in every crop cycle. 200 kg N ha^-1added in three split applications at V0, V6 and V10 stages.
T4: Traditional management with smaller planting density (70.000 plants ha^-1) without N in any crop cycle.
T5: 70.000 plants ha^-1 with 150 kg N in 2 out of every 3 crop cycles (no N in one of 3 cycles). N added in three split applications at V0, V6 and V10 stages.
T6: Traditional management (70.000 plants ha^-1) with 150 kg N in every crop cycle. N added in three split applications at V0, V6 and V10 stages.

The experiment used a split-plot design with the main plots assigned to the planting density (eco-intensification and traditional planting density) and sub-plots organized in randomized blocks with the different N management strategies. The plots assigned for each treatment are occupying the same physical location so we could measure the effects of N degradation or build up.

Only measurements on yield performance are carried out (14% moisture content grain yield).