LITTLE ROCK, Ark. (AP) — Arkansas growers are seeing Asian soybean rust spread at a faster and more damaging rate than they have seen in past years.
The fungus has been confirmed in 21 of the 35 Arkansas counties that produce soybeans, though the spread is likely greater, officials said Tuesday. Rain that has been over the state for days has helped the disease thrive and spread. The fungus travels on storm winds and flourishes in wet conditions.
Rain is forecast to continue through late Thursday in Arkansas, and growers can't spray fungicide without dry weather.
About 3 million acres are planted with soybeans in Arkansas, and the crop is worth about $1 billion. Because of extended foul weather in the spring, about 25 percent of the crop was planted after June 15, which means that portion of the crop is still maturing and is susceptible to damage from the fungus, officials said.
Jeremy Ross, extension soybean agronomist for the University of Arkansas Division of Agriculture, said rust has probably spread to all Arkansas counties where the crop is grown.
"We just haven't found it yet," he said. "Just a matter of picking the right field" to test, he said.
Other states where Asian soybean rust has been found this year, in varying degrees, include Alabama, Florida, Georgia, Louisiana, Mississippi, South Carolina, Tennessee and Texas, according to the U.S. Department of Agriculture.
Soybean rust, which arrived in the U.S. in 2004, causes crop loss due to premature defoliation, fewer seeds per pod and fewer filled pods per plant. Plants with the fungus exhibit cone-shaped pustules that erupt with spores of a light tan color, hence the rust in the name.
In past years, rust hasn't been much of a problem in Arkansas, often arriving after beans had matured.
"This year is by far the most severe case of soybean rust we have had in the state," said Scott Monfort, extension plant pathologist for the UA's Division of Agriculture.
Some growers sprayed earlier in the season and may need a second application, which adds costs to their production.
"The positive thing is that we do have fungicides that do control soybean rust effectively. As soon as it does dry up, there's a significant amount of acreage that will be spraying," Ross said.
The most intense concentrations of the disease are in an area near Pine Bluff and about 15 miles north of Brinkley. Both areas are along waterways, and fog has been lingering for hours in the morning.
"In these conditions — four days of rain — it's conducive everywhere," Monfort said.
The spike in rust this year does not mean more trouble is on the way next year. The fungus, which needs a living host to survive, attaches to soybeans and kudzu, both of which die off in the winter, Monfort said.
Rust was confirmed in Arkansas, Ashley, Chicot, Craighead, Crittenden, Cross, Desha, Drew, Jackson, Jefferson, Lawrence, Lee, Lincoln, Lonoke, Monroe, Phillips, Poinsett, Prairie, Pulaski, St. Francis, and Woodruff counties, according to the Cooperative Extension Service.