Research, genetics and data are what set Stine’s corn breeding program apart from industry competitors. Stine® hybrid seed corn is developed on a foundation of science, and the material we place in growers’ fields is time tested for proven performance. Over the last few weeks, we’ve explored how the birth of a hybrid begins at the Stine Seed Farm through inbred development and our self-pollinating process and how it advances through our nursery in South America to continue the selfing process. To cap off our series, we dive into our unique Pre-Elite and Elite Yield Trials and how our hybrid seed corn completes the final steps to prepare for launch in the marketplace.
For 21 years, Stine’s head of corn research Jason Behn has worked within the ebbs and flows of our corn breeding program. He’s spent many years researching, testing and bringing new corn hybrids to market. This year, he and his team are testing nearly 50,000 new hybrids through our Pre-Elite Trials program in 42 yield trial locations throughout the Corn Belt, ranging from North Dakota to Missouri and Michigan.
“Evaluating corn inbreds is an extremely important component of our corn breeding program,” says Behn. “It’s these inbreds that we cross to make our ‘test hybrids’ that advance through our Pre-Elite Trials. These are the hybrids that, through our research in the early stages of our program, have displayed a strong genetic background from their inbred parents. We won’t advance anything that doesn’t perform and that the data doesn’t back.”
What are Stine’s Pre-Elite Trials?
Stine’s Pre-Elite Trials are Stop 1 in a hybrid’s journey to commercialization. These hybrids have never been tested against other hybrids before. It’s here that they are “checked” against our current products in the system.
“Uniformity is key to our Pre-Elite Trials,” says Behn. “We make sure every variable is aligned, including fertilizer and herbicide applications, the soil types the hybrids are placed in, planting space and population. We even have a planter that is designed with compaction in mind so that every hybrid has the same tire tracks going by it. All hybrids have an equal playing field throughout the season in our Pre-Elite Trials.”
Before hybrids are placed in Pre-Elite Trials, they are grouped by maturity. The genetic background of the hybrid’s parents helps us determine the maturity of our test hybrids. It’s critical that each hybrid is planted in its correct maturity zone.
Once the hybrids have undergone a growing and harvest season in one of our 42 Pre-Elite Yield Trial locations, only the top-performing testers advance.
“Only 5% to 10% of test hybrids advance to the next phase in our program — Elite Yield Trials,” says Behn. “The hybrids that don’t make it through are disposed of. If they don’t show strong potential in our Pre-Elites and up against what’s in our current lineup in the market, there’s no value in moving them forward. Our vetting system is very thorough; we know that we’re advancing the right products each year.”
Once a hybrid “graduates” from the Pre-Elite Trials, their inbred parents undergo more selfing reps in our South American winter nurseries in Argentina and Guyana so that we can produce more material from both parents for additional hybrid crosses.
“A finished inbred is generally F7 or higher, so we continue to self the inbreds before Elite Yield Trials to get that material to the F6 and F7 level,” says Behn. “With each selfing generation, we’re lowering the heterosis, or simply continuing to purify the inbred.”
What comes next in our corn breeding program?
Stine’s Elite Yield Trials are the final stop on a hybrid’s path to commercialization. Hybrids typically spend up to two to three years in our Elite Yield Trials before advancing to market to ensure they have consistently met all performance checks throughout the program.
“In our Elite Yield Trials, we have more reps than our Pre-Elite Trials, meaning we plant more seed and conduct more research,” says Behn. “This allows us to review more data points, which ultimately ensures we’re looking at how that hybrid performs against several different environmental and agronomic variables. Only the best of the best advance, so it takes time and diligence to sort out the true and consistent top performers.”
In our Elite Yield Trials, new hybrids are evaluated not only against our current material in the lineup but also competitor hybrids. Like our Pre-Elite Trials, we ensure consistency in uniformity. We test all hybrids under multiple populations, row configurations and environments, but we do so in a way that ensures each hybrid, even our competitors’, is getting equal treatment.
“What’s a bit unique about our Elite Yield Trials is that we test in varying row configurations, including three 15-inch rows and then a 30-inch gap between the test hybrids,” says Behn. “That allows us to test the hybrids in multiple populations. The middle row is getting tested at a higher rate than the two outside rows. This gives us more data on how it will perform in different environments, row spacing and populations — something that makes Stine’s breeding program unique and helpful in providing a real-world look at how these hybrids will perform when they hit the field.”
Once a hybrid has proven itself, we take time to build up the seed stock so that it’s available to our grower customers. This occurs at our winter corn nurseries in South America and throughout our plot system in the U.S. From there, we begin the trait conversion process, where our top-performing material is combined with industry-leading traits. We also reserve conventional seed for growers who want high yield but without the addition of a trait.
“Even our conventional seed is the best out there,” says Behn. “We divide the good from the OK or even bad in our Pre-Elite and Elite Yield Trials so that, no matter the hybrid, growers are truly getting the highest-performing option in the bag. We don’t breed one-hit wonders in our program; our process and testing won’t allow it.”
To learn more about Stine’s industry-leading corn breeding programs and our selection of high-yielding corn products for the 2024 season, contact your local Stine sales rep today.