Soybeans under the gun in 2005 years ago
By ROWENA PLETT
Staff writer
Soybeans used to be a crop that farmers could plant without fear of disease or insect infestations. The plants were good for the soil as a nitrogen-fixing legume.
In recent years, problems have begun to show up requiring the use of pesticides and fungicides in some areas.
The newest threat is soybean rust. It was spotted in seven states in 2004 at the end of the growing season and is expected to spread. It came as close to Kansas as Missouri.
According to researchers, soybean rust looks similar to common diseases such as bacterial blight, bacterial pustule, or brown spot. However, the rust spore is identifiable by a bump in the middle which acts like a volcano, spewing out many other spores when it matures.
The spores are carried long distances on the wind. Fields become covered with clouds of spores. A soybean plant can be defoliated in only a couple of weeks.
Because the disease was researched years earlier in this country, several fungicides are available to treat it wherever and whenever it breaks out during the 2005 growing season.
Soybean growers in Brazil who were hit with soybean rust in 2003 are providing valuable lessons for U.S. farmers, the most important being that spray must coat all leaves including the lower ones for good control.
Farmers will need to be vigilant in inspecting crops so fungicides can be applied early enough to control the aggressive disease.
United States Department of Agriculture is in the process of developing a new national soybean rust alert system which will track the spread of rust through the growing season and let producers know where rust actually is in relation to their farms.
According to Doug Jardine, a plant pathologist at Kansas State University, the southeast corner of Kansas could be most vulnerable to the disease because of high precipitation and high humidity, conditions ideal for rust development.
Generally, the rest of the state has relatively high summer temperatures and low to moderate rainfall and humidity, which should be less conducive to development of the disease.
Aphids
Farmers also are warned to be alert for aphid infestations in soybean fields. Soybean aphids first were spotted in Kansas in 2003. They tend to be more numerous every other year, making 2005 a prime year for an increase in populations. Insecticides are used to provide control.
Control of soybean disease and insects will mean greater input costs for farmers in order to harvest a crop. Some farm analysts expect acreage planted to soybeans to drop as a result.