Weather conditions in Arkansas (during the first half of July) have been favorable for soybean diseases such as aerial blight and anthracnose. Current weather conditions (as of July 16) and the extended weather forecasts for the next 10 days are again not favorable for soybean rust development or spread. There is absolutely no need for Arkansas growers to be concerned about soybean rust at this time.

Since the last Soybean Rust Update, soybean rust has been confirmed in five more counties in the coastal regions of Alabama and Florida: June 28, on kudzu leaves in Florida’s Jefferson County (near Tallahassee); July 3, on kudzu leaves in Florida’s Hernando County (east of Orlando); July 3, on kudzu leaves in Alabama’s Escambia and Baldwin counties (near Mobile); and July 13, on kudzu leaves in Florida’s Leon County (also near Tallahassee).

Soybean rust has been struggling to spread and has been slow to develop so far this year. Conditions have been more favorable for spread and disease development in Alabama and Florida more so than anywhere else in the South. Soybean rust has only been found in a total of seven counties in three states in the continental United States this growing season and all these locations are near the coastal areas in southern Texas, southern Alabama, the panhandle of Florida and central Florida.

Please take note that soybean rust has yet to be found in historic rust sites in Georgia, Louisiana or Mississippi. Plant pathologists across the South continue to monitor soybean and kudzu plots located at sites that are well-known for early soybean rust development.

So far, rust has not spread much closer (to Arkansas). The nearest soybean rust confirmed to date is just east of Brownsville, Texas, and just west of Mobile, Ala. We will continue to monitor closely leaf samples from soybeans fields and kudzu patches across the southern U.S. for the detection and development of soybean rust. The good news, so far in the 2010 growing season: there has been no soybean rust suspected or confirmed within 300 miles of Arkansas.

For the latest on soybean rust movement and commentary, see http://sbr.ipmpipe.org/cgi-bin/sbr/public.cgi. In Arkansas, soybean/kudzu samples from counties north of Lincoln County should be sent to the Lonoke Lab. Soybean/kudzu samples from counties south of Jefferson County should be sent to the Monticello Lab.

All soybean/kudzu samples examined to date have been negative. We will continue to scout kudzu patches, soybean sentinel plots and soybean fields throughout the state.

I would like to ask county agents with soybean sentinel plots and/or kudzu patches to send in samples to the lab at Lonoke or Monticello.

I would like to express my thanks to the county agents that have sent in samples so far this season. I would also encourage consultants and growers to send in kudzu and/or soybean samples (at least 100 leaves) during the season if they suspect soybean rust.

If you have any questions or concerns please contact Cliff Coker (870) 723-5519, Scott Monfort (870) 659-0648, Jeremy Ross (501) 944-0621, Amanda Greer (870) 723-5563 or Amy Carroll (870) 258-2509.