I’ve written previously about why North Carolina corn growers should feel comfortable planting non-Bt refuge corn, but the performance of non-Bt hybrids in the 2022 OVTs and 2023 OVTs adds one more reason to the list. We have a collaborative project to evaluate non-Bt and Bt hybrids for yield on growers farms across the state. While these on-farm tests are planted in strips using grower equipment (much like the on-Farm Cotton Variety Evaluation Program), the OVTs are planted into smaller plots. There is value in both approached and we hope to make the on-farm non-Bt and Bt information available soon.
Growers can use the Variety Selection Tool to search for these hybrids that were planted in the 2023 OVTs. An identifying column entitled BT Status will identify whether the hybrid is a Bt or non-Bt hybrid when querying or filtering the data.
Eight non-Bt hybrids were included in nine OVT locations in 2023. All were late or mid-maturing hybrids produced by DEKALB and one was from Pioneer. This year one non-Bt hybrid yielded exceptionally well across all locations. It was the second highest yielding corn hybrid across all locations averaging 222.7 bu/A statewide. Other non-Bt hybrids did not yield as well across all locations, but three were among the statistically highest-yielding hybrids in one or more locations. This highlights the fact that:
1) A non-Bt hybrid with good genetics can perform as well as many Bt hybrids when planted on time and placed in the correct environment.
2) A non-Bt hybrid placed in a poor environment will perform poorly, even in the same relative maturity as other Bt hybrids- genetics matters!
We have measured this before. Here are yield results from three non-Bt hybrids grown in replicated trials from 2019-2023 (5 years) at the Tidewater Research Station in North Carolina. Note that the average yield difference between the top yielding non-Bt hybrid and the lowest yielding non-Bt hybrid across those five years is 22 bu/A. Growers should work with their seed dealer to ensure that they are planting the correct non-Bt refuge hybrid for their environment.
