Texas Cooperative Extension plant pathologist Tom Isakeit says recent occurrences of Asian soybean rust in Texas commercial fields has been limited to Liberty County, which is adjacent to Harris County in East Texas. Though only detected in a single county, Isakeit adds that is was found in many commercial fields.

“There was also some in the sentinel plots in Beaumont. It was prevalent in late-maturing beans, but not early ones,” he says.

According to information on Isakeit’s Web site, http://soybeanrust.tamu.edu, rust has not been detected in other areas of Texas, although most of the state’s crop has been harvested or is too mature to be at risk for yield losses from rust.

There is potential for rust over-wintering in the state, Isakeit says, because the rust fungus can only survive on living plant material.

“If we don’t get a freeze in the Houston area later this year, it will survive on that kudzu near Dayton [in Liberty County],” he says. “It may also blow in and affect soybeans in the Lower Rio Grande Valley later on this year, but I don’t see that part of the state as a source of spores for next year ... at this time.”

The soybean rust fungus was introduced to the United States in Florida in 2004, probably by hurricane winds. Findings of the disease in south and east Texas indicate it could move along the same northerly path as other rust diseases that affect corn and wheat.

If producers suspect they have rust — especially on a plant other than soybean or kudzu — they should submit a sample to their county agent or directly to the Texas Plant Disease Diagnostic Laboratory in College Station. The lab can be reached at (979) 845-8032.