Researchers at the USDA laboratory at Weslaco, Texas, have confirmed Asian soybean rust on soybeans at the Texas A&M Experiment Station (Hidalgo County).

Texas A&M agronomist Tom Isakeit says plant pathologist Marvin Miller reported the finding after examining a sample collected by technician Robert Saldana February 14.

“Identification was confirmed with an ELISA test by Larry Barnes of the Texas Plant Disease Diagnostic clinic on February 16,” Isakeit says.

John McKemy, PCR, and Laurene Levy, with the USDA-APHIS laboratories, also confirmed the sample as Asian soybean rust on February 22.

“This was in a field I had surveyed in December, 2005, and had not seen any symptoms of rust,” Isakeit says. “As of February 14, the field was being harvested.

“Miller reported that rust was quite prevalent on plants at the ends of the rows. These plants were a little less mature than the rest of the crop.”

Isakeit says the field is about one acre in size and will not serve as a source of spores, since it has been harvested. “This field was planted much later than usual. Normally, soybeans in this part of the state would have been harvested by mid-December.

“The soybean sentinel plot in Weslaco was planted in mid-February. There are no other soybeans around and there is no kudzu in this area of the state.”

Isakeit says prognosis for the 2006 season is uncertain. “It depends upon the weather in the spring. This is a situation where the sentinel plots in south Texas will really prove their worth,” he says.


e-mail: rsmith@prismb2b.com