19/8/21, 00:00

Spatial arrangement for corn early planted in high potential environments

In places with groundwater in southeast Cordoba, Aapresid's producers are testing the impact of narrow rows on weed control and yield. Here are some results.

Florencia Cappiello (Aapresid Press) 

Chacra Aapresid in Justiniano Posse has among its objectives adapting management  strategies to take full advantage of the potential environments with groundwater in the  region. 

In recent growing seasons, they tested the impact of narrowing the distance between  rows as a strategy for planting corns in these high potential environments. "Including a  pneumatic seed drill initially designed to adjust spacing in soybean, we tried to narrow the distance in corn from 52 to 40 cm," explained Julio Perez, producer of the Chacra. 

"The aim is to know the impact of changes in the spatial arrangement on yield, costs  and colonization of difficult weeds, which have grown exponentially in recent years,"  explained the project's technical manager, Franco Bardeggia. 

For weed control, the results have shown that narrowing the rows (from 52-70 cm to  40 cm) brings forward the moment of furrow closure to V5-V6. Although at flowering all  spacings achieved equal percent cover and interception, the plots sown at 40 cm left  furrows clear of weeds. 

In terms of yield, the different spacings did not affect this variable. Specialist Gustavo  Maddonni (FAUBA) studied in depth the causes behind this behavior. "The spatial  arrangement - given by planting density and row spacing - affects crop structure. This  structure determines the efficiency of interception and use of the radication, and  therefore, the yield." 

Moving rows closer together should increase interception efficiency. This is true when  low densities are used. However, at high densities - which are those usually used in  high potential environments - this increase in intersection is only evident in vegetative  stages; at flowering no differences are observed. As there is no difference in capture,  there is no difference in yield. 

In restrictive environments where lower densities are used, row narrowing can even  negatively affect yield. "Narrowing rows can lead to higher water consumption in  vegetative and a higher risk of water restriction around flowering."

Finally, it was analyzed the impact of narrowing between rows on crop condition at  harvest. "The shorter spacing generated taller plants, and although there were no  harvest problems, those lots that suffered some storm or wind showed overturning,  broken plants and incidence of diseases that in some cases produced losses of 400- 1500 kg/ha." 

To conclude, Bardeggia explained that groundwater allows stabilizing and increasing  yields, but as long as there is a well-adjusted management of variables such as spatial  arrangement."