Source: USDA Soybean Rust website

Soybean rust has been confirmed today on soybeans in Tift County in south central Georgia. This is the first report of rust in this county in 2006.

State commentary:

Crop Growth Stage Last Modified: 08/04/06 11:14 AM

Most of our soybean sentinel plots (MG-IV an MG-VI) are now at the R7+ growth stage as of 8/4/06. Commercial soybeans in our state range from about R1 to R7 stages.

 

Observation and Outlook - Disease Last Modified: 08/07/06 01:37 PM

Report for 7 August:
Soybean and kudzu sentinel and non-sentinel sites continue to be monitored for soybean rust. Rust was confirmed today on group IV soybeans growing on a industry research farm in Chula, GA. Chula is located in Tift County in southcentral GA. This is the first rust find in that county. A small leaf sample (<10 leaflets) was submitted to the University of GA diagnostic clinic, and rust was confirmed with dissection microscope. It is possible that the recent rain events could have moved spores from north Florida.

 

Observation and Outlook - Insect Last Modified: N/A

Commentary Not Available

 

Scouting and Management - Disease Last Modified: 08/06/06 07:39 PM

From 6 August: Although Asian soybean rust has been confirmed on kudzu in Miller and Brooks Counties and on soybean research plots in Brooks and Decatur Counties, it has really not spread much at all this year, likely due to hot and dry weather. NOTE: frequent storms and flowering-reproductive growth stages of our commercial crop could easily rekindle this disease across the state.

Soybean producers in the SW corner of Georgia should be on high alert for soybean rust. The most conservative approach to managing this disease would be to make a fungicide application during the blooming growth stage and follow with a second 14-28 days later if conditions favor disease spread.

Many growers may also choose to wait to apply the fungicide application UNTIL we are able to document rust spreading in our sentinel plots and research plots. For example, though rust was found on soybean plants in Attapulgus, Decatur County (1 leaf of 100) on 3 July, we have NOT found the rust again on 10 July, 17 July, 24 July or 31 July. We have also NOT found rust in sentinel plots in Moultrie (SunBelt Expo) or elsewhere.

Many soybeans will be approaching the R3-pod formation growth stage soon. Growers may wish to mix a fungicide, for example chlorothalonil or fungicides, with dimilin or boron applications to increase disease control (e.g. frogeye leaf spot) as well.
 

Scouting and Management - Insect Last Modified: N/A

Commentary Not Available

Plant Pathologist
Layla E. Sconyers
Post-Doctoral Research Associate
Dept. of Plant Pathology
Email: lsconyrs@uga.edu

Currently rust has been found on this year's soybeans in nine different counties in five states(AL,FL,GA,LA,MS), the rest of the finds have been on kudzu. A total of 29 counties have reported rust this year and include five in Alabama, 13 in Florida, six in Georgia, three in Louisiana, one in Texas, and one in Mississippi. Spore trapping continues throughout the U.S. using both active and passive traps. Any positive spore trap information does not imply infection has taken place and plant samples are used exclusively for recording positive rust occurrence. Dry to very dry conditions have prevailed in the spore source regions and movement to new areas has been slow.