As a University of Missouri Extension professor, Gene Stevens’ focus is on researching ways to improve production practices for numerous core crops, such as corn, rice, cotton and soybeans.
Stevens, who is located at the Fisher Delta Research Center in Portageville, Mo., recently developed the Crop Water Use App, which assists farmers with their irrigation scheduling. Always aware of the changing technology trends, Stevens has continued to make the app as useful for users as possible.
The app does not currently distinguish between soybean maturity groups, and Stevens is looking to see if that needs to change.
“In the program, a crop coefficient adjustment factor for soybean, developed in 1995 by Wayne Decker, is multiplied by daily estimated short crop evapotranspiration, calculated using the Penman-Monteith equation and local weather data,” Stevens said. “The adjustment factor divides the season into vegetative, flowering, pod and seed development, and physiological maturity growth stages.”
When Decker developed the adjustment factor, he was a professor emeritus and weather consultant with MU’s Commercial Agriculture Program. His work has been used by Stevens as part of the app.
Stevens is currently conducting field tests in Portageville, studying the weekly changes in light interception from 10 soybean varieties. Those varieties range in maturity group from 4.0 to 5.9. That maturity group range is most common in the southern part of the Missouri.
“Each of our 10 soybean varieties has a different maturity,” Stevens said. “We have a really good representation of Missouri through this program. We wanted to focus on the maturity groups common to our climate and soils. Soybeans grown in Minnesota, for example, wouldn’t do as well here because of the differences.”
The light interception measurements include percent canopy closure, leaf area index and normalized difference vegetative index. Stevens will use the data from the light interception measurements and compare it to the crop coefficient adjustment factor currently used in the app. The goal is to see if the data is vastly different. If it is, Stevens will look to incorporate the best data into the app.
“This research will tell us if we need to have different coefficients for the different maturity groups,” Stevens said. “At the end of the day, we want the users to have the best data available. We want it to be useful in many ways.”
The work is funded by the The Climate Corporation, a digital agriculture company with a focus on weather, soil and field data. The company is owned by Bayer Crop Science.
Stevens will go into more details about his work, including sharing the early data his team has collected on this project, during the 57th Fisher Delta Research Center field day. The event will run from 9 a.m. to noon on Friday, Aug. 31, at the Center in Portageville. The field day will focus on how the Fisher Delta Research Center is “Guiding the Future of Delta Agriculture.”
In addition to this project, Stevens is doing a variety of work at the Fisher Delta Research Center related to several traditional and non-traditional crops. His projects include researching the importance of crop rotations, optimizing variable rate irrigation, fertilization and seeding, and evaluating potential future crops for the Bootheel. Stevens has conducted cover crop research for more than 20 years as well.