Koch Agronomic
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Corn Partitioning and Nitrogen

Plant growth is dependent upon many things, including inputs. And one of the most important input investments you’ll make is nitrogen fertilizer. To maximize nutrient use efficiency, you need to know how and when the plant directs the nitrogen where it’s needed throughout the growing season in order to promote crop growth and productivity.

"Improving your understanding of crop nutrient demand and how the plant uses that nutrient can help you implement a 4R nutrient management strategy to help minimize nutrient loss and optimize your nitrogen fertilizer investment,” said Derek Rapp, technical agronomist for Koch Agronomic Services (Koch). “An important part of that strategy is using a nitrogen stabilizer."

Supply and Demand

Simply put, partitioning is how plants use nutrients. Throughout the plant’s growth cycle, there are varying levels of demand for nitrogen, so the right supply must meet the demand through the entire season.

Nitrogen absorbed by the roots is transferred to the different components of a plant. In corn, for example, nitrogen would be used to build the cells for grain, tassel, cob, husk leaves, stalk, leaf sheaths and leaf blades.

The chart below indicates at what growth stage different components of the corn plant require nitrogen. The curve illustrates where the nitrogen goes once it is removed from the soil and taken up by the plant. It also shows the timing of nutrient uptake follows a traditional s-shaped pattern with the majority of the total plant uptake during VT/R1.

Nitrogen Uptake and Partitioning in Corn¹

The three stages of plant growth to focus on are emergence, vegetative growth and reproductive growth.

• Emergence (VE-V5): Less than 20 percent of nitrogen uptake occurs during this stage. Stabilizing pre-plant and at-planting nitrogen is critical at this stage as it’s especially vulnerable to loss during this time.
• Vegetative growth (V6-VT): Approximately 60 percent of total nitrogen uptake occurs between V6–VT. Nitrogen availability is critical as your crop needs to uptake the most nitrogen at this point.
• Reproductive growth (VT/R1-R6): At R1, the plant is beginning to prioritize nitrogen for grain production. The plant remobilizes the remaining nitrogen from the stalk to grain. At this stage, corn will continue to absorb nitrogen from the soil, in the form of nitrate, through maturity at R6.

Protecting Your Applied Nitrogen

Now that we know when nitrogen uptake occurs, it’s important to decide how you’ll protect your applied nitrogen.

CENTURO^® nitrogen stabilizer from Koch is a nitrification inhibitor for anhydrous ammonia and UAN. With CENTURO, you extend the window of protection by slowing the conversion of ammonium to nitrate, holding the nitrogen in the ammonium form three times longer than without an inhibitor.²

"If you’re applying early spring anhydrous ammonia, which can be susceptible to below-ground losses from spring rains, CENTURO helps protect the nitrogen so it’s more available when crop demand is at its highest from V6 through grain fill,” said Rapp. “Knowing CENTURO can slow the conversion to nitrate can give growers peace of mind that more nitrogen will be available when the plant needs it most."

Doug Graber and the growers he advises would agree. As the agronomy manager for Producers Cooperative Association (PCA) in Kansas, he has been impressed with the performance of CENTURO.

"CENTURO helps take the guess work out of planning what (nitrogen) will actually be available when the crop needs it,” said Graber. “We exist to help our customers realize higher ROI and revenue per acre. But the big sales pitch is to protect their investment and know that it’s going to be there when the crop needs it."

Learn more about nitrogen management and how CENTURO can help protect your investment and optimize yield potential. Visit KochAgronomicServices.com or contact your Koch representative.