Corn plants stuck in ponded or saturated soils about V5, when the growing point was coming above ground, made decisions that will lead to reduced yield.
Sensing less than average growing conditions, one decision made early went against good yield. That was number of rows of kernels that the plant would put on the ear.
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Dave Nanda, plant breeder and consultant for Seed Consultants, Inc., says that plants determine things like row number per ear early. Much of that determination is tied to genetics, he says. How many rows of kernels a specific hybrid will put on per ear is highly genetics-related.
However, it's not all genetics.
"Plants can make adjustments based on the conditions that they see when they are making these decisions," Nanda says. "The plant's goal is to produce as many viable seeds as possible. If it thinks conditions are good, it will put on more rows to grow more seeds. If it senses conditions aren't favorable, it will put on fewer rows because it wants to make sure the seeds that it makes are viable."
Some parts of the country saw good growing conditions all season long. When plants reached the stage to make decisions about row number, plants sensed favorable conditions and went ahead with solid row numbers.
Where conditions were especially favorable, they may have even bumped up row number 2 or 4 rows higher than what that hybrid would normally produce.
Nanda carries around a broken ear this fall to illustrate the point. At a field in central Indiana, a farmer pulled off ears with 22 rows of kernels. The hybrid typically puts on a large number of rows, but 22 was high even for the hybrid, Nanda says.
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In another field with a different hybrid and where conditions weren't as favorable due to wetter soils, the same farmer pulled off ears with 16 rows of kernels.
This is a good year to illustrate how number of rows of kernels per ear is determined by both genetics and the micro-climate around the plant, Nanda concludes.