The question “Do Traited Corn Products such as corn borer or corn rootworm hybrids need more nutrients than non traited hybrids?” The response is yes in that traited hybrids have increased yields by 5-20% vs. non traited hybrids, and will need and remove more nutrients just based on the increased yield.
To steal a phrase from Paul Harvey here is “The rest of the story.” In the past we have known that certain genetic types or genetic families have shown greater response to increased rates of Nitrogen (N) or split applications of Nitrogen than others. From a trait perspective the healthier the plant is the better the trait expression is throughout the plant, which would explain a greater response to increased or split applications of Nitrogen.
Recent data suggests that Traited hybrids pull or use nutrients later in the growth stage of plants which in regards to Nitrogen would explain why Traited products show a bigger yield increase to an increased rate or split application of Nitrogen vs. a Non Traited product.
|
Nitrogen Uptake |
||
|
Growth Stage |
Non Traited |
Traited |
|
VT (Tassel) |
78% |
58% |
|
R4 (Dough) |
94% |
86% |
|
R5 (Dent) |
98% |
90% |
Other incidental data suggests that we are also seeing similar growth stage use rates in Potassium (K) as we are in Nitrogen.
|
Potassium Uptake |
||
|
Growth Stage |
Non Traited |
Traited |
|
R2 (Blister) |
100% |
86% |
|
R5 (Dent) |
100% |
The use of Potassium in later growth stages of Traited hybrids may explain some increased incidents of stalk cannibalization. (Potassium is a critical nutrient in stalk strength.) Potassium is taken up into the plant through soil water uptake by the roots. If soils are dry due to drought or lighter soil types Potassium uptake will be reduced. Other factors that can and will reduce Potassium uptake are a poor root system from compaction, rootworm feeding, or a genetically poor rooted hybrid. If you combine a droughty soil with a compromised roots system you have the potential for disaster.
Ways to increase your Potassium availability would be to increase your Potassium rates when you spread fertilizer, spread more often, or if you are sidedressing 28% or 32% N, you could substitute Potassium Ammonium Sulfate for Ammonium Sulfate.
In conclusion the obvious is as we increase our yields we will need to replace more nutrients that we have used. In the future how and when we replace those nutrients maybe different than what we have done in the past.
For more information regarding nutrient timing and uptake contact your local Central Valley Agronomist. Have a safe and successful spring season.
- Brian Weller
