Virginia Tech researcher says Virginia's soybean crop may be out of danger
Virginia's soybean crop may be out of danger for this year from the disease called Asian Soybean Rust. Virginia Tech scientists at the Tidewater Agricultural Research and Extension Center at Suffolk have tested samples of soybean leaves using methods recommended by U.S. Department of Agriculture to detect the fungus. The results of the 90 samples in five fields in the major soybean-growing region of the state were all negative.
David Holshouser, soybean agronomist and associate professor in the College of Agriculture and Life Sciences at Virginia Tech, said that the scientists will continue to monitor Virginia fields for several more weeks. The effort is part of a statewide plan to minimize losses to Virginia's soybean producers.
"The soybean crop is at a stage that an infestation would not be devastating," Holshouser said. Full season soybeans, which were planted in May, are out of danger. In about two weeks the double-cropped soybeans—those which were planted in June and July after harvesting of wheat or barley—will be at a stage where there would be little yield loss.
"Even if it were found today, it would take weeks for the fungus to build up to conditions that will damage the crop," Holshouser said. He added that the fungus is known to survive over the winter in Florida on plants such as kudzu if weather conditions are good. Monitoring will continue throughout the United States.
"The test we are using in the field is a serological test developed by EnviroLogix Inc.," he said. It is the first rapid test to detect symptomatic leaf spot caused by the soybean rust pathogen before it can be visually detected. It is an immunodiagnostic test and provides an answer that indicates only if the pathogen is present or absent. More precise testing is done at the designated laboratories.
Soybean's farm gate value in Virginia has ranged from $75 million to $100 million annually. Several years ago when the danger from Asian Soybean Rust became imminent, Virginia agriculture leaders formed the Soybean Rust Task Force. It created a plan that includes educational programs for Virginia Cooperative Extension agents, crop advisers, growers, and others to understand what the disease looks like and what action to take if it is found. It established a monitoring system to identify Soybean Rust as well as the soybean aphid, also a major problem.
Research continues at Virginia Tech and other places to find soybean varieties resistant to Asian Rust, he said. Until then, if it is found growers can use fungicides to protect their crop. However using fungicides is very costly and using them may not be a viable economic alternative for Virginia growers.
The agriculture organizations that are part of the task force include Virginia Tech, the Virginia Department of Agriculture and Consumer Services, Virginia Soybean Association and Virginia Soybean Board, the Virginia Farm Bureau, Syngenta Crop Protection, Inc., Virginia Crop Production Association, Colonial Farm Credit, and the U. S. Department of Agriculture's Animal and Plant Health Inspection Service, Plant Protection and Quarantine, and its Risk Management Agency.