Screening Program Provides Rx For Soybean Diseases: January 1999 Soybeans Today

Soybeans Today January 1999

Screening Program Provides Rx For Soybean Diseases

By Fred Miller

Two years ago, the soybeans in some of Randy Pettingill's Conway County farm fields were withering.

"It was real good land, it was irrigated and the beans were devastated. I couldn't figure out what was wrong," Pettingill says.

A field verification test revealed that he had one of the worst populations of root knot nematode in Arkansas.

Conway County Extension Agent Howell Thompson helped Pettingill find a resistant soybean cultivar recommended by the University of Arkansas, Division of Agriculture.

"The infected land went from around 25 bushels per acre one year to about 50 bushels the next year," Pettingill says. "The difference was phenomenal. The right variety makes all the difference."

Pettingill was able to find a resistant soybean thanks to an Arkansas Agricultural Experiment Station screening program supported by the Arkansas Soybean Promotion Board.

"Phenomenal numbers of new cultivars have been released in recent years," says Terry Kirkpatrick, a plant pathologist at the U of A's Southwest Research and Extension Center at Hope. "Cultivars were released so rapidly, they outpaced the research that gives farmers the information they needed to make choices."

New cultivars often came with little information, often rated as simply "resistant" or "susceptible" to diseases. "Most plants have varying degrees of resistance to disease that affects their yield potential," he says. "We wanted to get uniform data that could help farmers select the cultivars that best suit their needs."

Nurseries are set up to create the conditions where soybean diseases thrive. The worst diseases are evaluated in nurseries at SWREC to avoid the danger of infecting major growing areas. "Cultivars are rated in a standardized scale called the Horsefall-Barrett scale -- a zero to 11 scale, with 11 being the worst and zero being no disease -- so that everyone is essentially singing off the same page," Kirkpatrick says.

These results are converted to a standard scale that rates plants as resistant, moderately resistant, moderately susceptible or susceptible to specific diseases.

Results of disease screenings are used to update the SOYVA program, a computer model farmers can use to match varieties to their field conditions.

The data also goes into "The Soybean Update," a publication listing soybean varieties recommended by the U of A. It includes the information about each cultivar -- including ratings for disease resistance or susceptibility -- that farmers need to select their seed. The publication is available from the Cooperative Extension Service.

"We wanted to gather all the information from all the researchers working on this into one publication so we could help farmers sort through hundreds of varieties and choose the ones that will best suit their field conditions and history," Kirkpatrick says.

"I'm a stand-up man for the University of Arkansas, and the money I spend on the promotion board checkoff is money well spent," Pettingill says.

"I use the SOYVA program and I use all their recommendations," he says. "The university's researchers know what they're doing, and they're making me money."

Soybeans Today January 1999
Table of Contents

For additional information about any board-related activity contact:

Arkansas Soybean Promotion Board
ATTN: Brandy Carroll
P.O. Box 31
Little Rock, AR 72203-0031
Phone: 501-228-1268

Web Services by Aristotle Web Design.
Privacy Policy