Heat Bringing Corn Development And Stress

Jul 24, 2015

By Dennis Todey

As of the latest USDA-NASS report on Monday 20 July, 43% of corn had tasseled in South Dakota, which is ahead of last year and the 5 year average. That number will increase again next week with temperatures varying around seasonal averages over most of the state. Additional late week heat will continue to accumulate degree days. While the additional heat has been beneficial for the additional degree days, the heat has also started to introduce stress in corn in several locations. Most degree day accumulations in the state are close to average assuming reasonable planting date.

Stress Factors: Heat, limited precipitation & increased water use

The reason for the crop stress is not only the additional heat. Most of the temperatures have not reached well into the 90s, which would be expected to increase stress. Two additional climate impacts are at work. Large portions of the state have received limited or no precipitation in the last 2-3 weeks. With the early season moisture, the initial dryness was not an issue. Now the issue is starting to show up because of the increased water use that occurs during the reproductive stages of corn development. Corn uses the largest amount of water at this time.

During the cooler days in the early part of the month daily crop water usage could likely have been less than 0.2” per day. With the hotter temperatures in the middle part of the month that amount could reach a third of an inch or more, especially in the warmer/drier locations in the state. Data for Brookings estimates crop water use at over 4 inches for July. The water use was only balanced by 1.42 inches of rainfall.

Thus, corn is drawing into the soil moisture reserves everywhere in the state. Lighter soils with less soil moisture holding capacity likely will not have enough moisture to supply the full crop water need. Stress is introduced, starting to reduce yield potential.

Click here to see more...

Video: Seeing the Whole Season: How Continuous Crop Modeling Is Changing Breeding

Plant breeding has long been shaped by snapshots. A walk through a plot. A single set of notes. A yield check at the end of the season. But crops do not grow in moments. They change every day.

In this conversation, Gary Nijak of AerialPLOT explains how continuous crop modeling is changing the way breeders see, measure, and select plants by capturing growth, stress, and recovery across the entire season, not just at isolated points in time.

Nijak breaks down why point-in-time observations can miss critical performance signals, how repeated, season-long data collection removes the human bottleneck in breeding, and what becomes possible when every plot is treated as a living data set. He also explores how continuous modeling allows breeding programs to move beyond vague descriptors and toward measurable, repeatable insights that connect directly to on-farm outcomes.

This conversation explores:

• What continuous crop modeling is and how it works

• Why traditional field observations fall short over a full growing season

• How scale and repeated measurement change breeding decisions

• What “digital twins” of plots mean for selection and performance

• Why data, not hardware, is driving the next shift in breeding innovation As data-driven breeding moves from research into real-world programs, this discussion offers a clear look at how seeing the whole season is reshaping value for breeders, seed companies, and farmers, and why this may be only the beginning.