Visit someone who works in the corn industry, and even if it is a social visit, the conversation will likely turn to corn. And if you happen to be talking outside with a cornfield still standing in the background, don’t be surprised if that person wanders off into the corn. They may be trying to determine which hybrid is planted from various visual traits.PREHARVEST CHECK: What can you learn by checking corn right before harvest? You can learn how to tell hybrids apart, and you can pick up on diseases and abnormalities.
For a real treat, walk into a cornfield where two hybrids are planted side by side with a plant breeder. “We will be able to tell where one hybrid ends and the other begins across the field,” says Dave Nanda, a plant breeder and crops consultant for Seed Consultants Inc., sponsor of Crop Watch ’16. Sure enough, he soon found the division between two hybrids in the Crop Watch '16 field.
Here are four ways Nanda could visually tell that the hybrid on his right and the hybrid on his left were two different hybrids with distinct genetic differences.
1. The tassels are shaped differently.
“If you can’t tell looking up at them, break two off and hold them side by side,” Nanda says. “In this case, one has more branches and more vegetative-type growth than the other.”
A tassel doesn’t need extra growth, he says. Many newer hybrids have fairly compact tassels.
TASSEL DIFFERENCES: Corn is corn, right? Not if you’re walking alongside a trained plant breeder. Note the difference in the tassels on the left and on the right. They are from two different hybrids.
2. The ears are at different heights.
In this case, the ears on one hybrid were nearly a foot closer to the ground than on the other hybrid. Nanda prefers the lower ear height in general. He believes hybrids of the future will tend to be shorter with lower ear height placement than many hybrids of the past.
2 EAR HEIGHTS: Two hybrids were planted in blocks across the field. The row on the right is a different hybrid than on the left. Note the lower ear placement on the corn on the right.
3. Size and shape of kernels and rows on ears may vary.
Ears on one hybrid in the Crop Watch field routinely had 16 rows of kernels around the ear. The other routinely had 14 rows. However, the girthier ear with 14 rows contained much deeper kernels than the other ear. “Always break ears apart and compare the butt ends to see how rows and kernel size compare,” Nanda says.
2 EAR TYPES: Note the ear on the right has 16 rows of kernels, compared to 14 rows on the ear on the left. However, kernels on the left ear are much deeper. These factors are linked to genetics.
4. Maturity of hybrids varies.
There was enough difference in these two hybrids that the black layer was distinct in kernels on one, but less distinct on the other. One hybrid was definitely at least a couple of percentage points of moisture drier when checked in this preharvest walk.
“Maturity is a factor you want to consider carefully,” Nanda says. “You hope you pair up two hybrids with similar maturity when you are placing pairs of hybrids in the same field.”
MATURITY DIFFERENCE: Kernels on this ear, which was the ear on the right in the picture with two ears, had reached black layer and were lower in moisture than kernels on the other hybrid.