"What that tells you is that we may be over-watering in this location if we use current ET network models estimation and water the field at 100 percent ET level," he said.

Marek said the evapotranspiration network corn model is based on older genetics and is used across the entire Texas Panhandle region, so things may not be specific for any one variety, area or newer genetics.

Xu said to get F1 hybrid seed requires two steps in the breeding program: developing parental inbred lines and crossing the inbred lines to make a hybrid.

"It takes eight generations to develop an inbred line," Xu said. "If you have two seasons per year, it will take four years to develop an inbred line."

But even if an inbred line looks promising, it doesn't mean success, he said.

"You can develop a nice-looking inbred line, but it does not mean it will make good babies," Xu said. "So the second (step) is to cross the inbred lines and find the good babies. That's the F1 hybrid. And that takes another three or four years, so it takes about seven to eight years to develop a good hybrid."

Xu said he has developed several experimental hybrids from his breeding program, estimating that every year a minimum of about 500 hybrids are generated, but only about 1 percent are good ones.

Marek said the difference between the 75 percent and 65 percent of ET seems to be the break-over point in terms of yield reduction for many of the hybrids. Some of the work done here has been cutting-edge research in both corn breeding and irrigation management and the increased yields support that.

"The ear length sitting on that stalk is a little shorter, and certainly the circumference and diameter is, and the kernel fill is not as good," Marek said.

"The days are coming when you will pick a targeted water level and a genetic variety to match that production level," he said. "And the combinations that will be available are going to become increasingly confusing to producers."