Published on 12/17/02

'Crops' planted, grown, harvested in minutes

By Sharon Omahen
University of Georgia

With a computer program, scientists across the globe can now plant, tend and harvest "crops" in just minutes.

The software is called Decision Support System for Agrotechnology Transfer, or DSSAT. It was created by a team of researchers from the universities of Georgia, Florida, Hawaii, Guelph and Iowa State and the International Center for Soil Fertility and Agricultural Development.

DSSAT is a computer model that allows the user to simulate a crop's growth, yield, water and nutrient requirements and the impact of the environment.

The program didn't develop overnight. In fact, the software's fourth version will be released in early 2003. About 40 researchers and graduate students from across the globe met on the UGA experiment station campus in Griffin, Ga., Dec. 9-18 to see the newest DSSAT software.

"Our goal this week was to introduce the newest Windows-based version of DSSAT and make sure the users understand and can use our system," said Gerrit Hoogenboom, a DSSAT developer and an agricultural engineer with the UGA College of Agricultural and Environmental Sciences. "We definitely don't want it to be on shelves collecting dust when it should be put to use."

Don't conduct all research on computer

Hoogenboom told the first DSSAT Version 4 users not to rely solely on the software for their research data.

"The results you obtain from the software are not ultimate truths, and they're not meant to replace real experiments, real data or critical thinking," he said. "Anytime you run a model you should question the results."

Though not a substitute for the real thing, the computer model can have great value to researchers.

"The trial-and-error approach is expensive," said Jim Jones, a DSSAT developer and a UF agricultural engineer. "With DSSAT, we can couple the systems approach with experiments. As P.G. Cox said, agricultural science is not a science unless it predicts and then tests its predictions."

The DSSAT software allows the user to simulate the growth of peanuts, sunflowers, sugarcane, wheat, soybeans, rice, tomatoes, sorghum, millet, barley, potatoes, corn, cowpeas and dry beans. Cotton will soon be added to the list.

"Those who use DSSAT now are sharing their work and their data via a computer listserv," Jones said. "In this way, the software is contributing to the whole scientific community."

Helping farmers identify and solve problems

The crop-simulation information will be shared with farmers.

"Our goal is to educate the people who talk to farmers directly," said Ken Boote, a DSSAT developer and UF agronomist. "Consultants, ag industry representatives and extension agents have the potential to spread the word to farmers. It's a technical type of transfer, so only farmers with interest in this technology would benefit from actually using the software themselves."

Boote says the way the software presents the data is an essential part of the success of DSSAT.

"You can't give numbers that no one can understand," he said. "Our program calculates crop growth and development in a mathematical sense and then shows it visually and graphically."

DSSAT has also been used as an effective tool after a crop has been harvested to identify the source of production management problems.

"It's a way to see the whole picture and what is limiting the crop," Boote said. "The software actually works better this way."

Software applications unlimited

In the early stages, the DSSAT developers tested the software using four years of real-crop data from Florida peanut farms.

DSSAT has been used on food security projects in Africa and other developing countries, too, and to study the impact climate change has on food production, he said.

"It's been used in Arkansas to help with early-season soybean plantings, in Kentucky for determining planting dates, in Georgia for predicting agricultural water usage and in Africa to diagnose yield loss of peanut crops from disease," Boote said. "The list of applications is never-ending."

Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.