Asian soybean rust continues to spread across much of the U.S. southeast, and west Tennessee is the latest location where the rust has been discovered. The rust has been confirmed in Tennessee on leaf samples taken from Shelby County plots.University of Tennessee soybean plant pathologist Melvin Newman and University of Tennessee soybean agronomist Angela Thompson believe there is a low level of rust spores currently in the field. Soybean rust prefers high humidity and cloudy and rainy conditions, weather conditions typical for this part of Tennessee, as well as much of the American southeast. If these conditions flourish, Newman believes it could still take up to 30 days before 1 percent severity is reached in most fields.
Newman and Thompson believe spraying for the rust should only be considered by west Tennessee growers at this point. Specifically, those producers in west Tennessee with beans between R1 and R5 growth stages that have not been sprayed with fungicide recently should consider spraying now. Growers in middle and east Tennessee do not need to spray at this time according to the University of Tennessee Extension Service.
Tennessee has experienced a lot of rain during this growing season, so soybean producers in the Volunteer State are expecting good yields at this time. In 2007 soybeans brought in $196 million in cash receipts for Tennessee farmers. This year’s yield is expected to be even bigger.
In addition to Tennessee, soybean rust has been found in Arkansas, Alabama, Mississippi, and Georgia, and South Carolina, all neighboring states to Tennessee. Florida, Louisiana, and Texas have all been affected by the rust too. Though the rust cannot survive the Tennessee winters, the wind-borne spores can still be blown in from other states further south.
Prior to this year, soybean rust was discovered in west Tennessee in 2006, 2007, and 2008. Asian soybean rust was first discovered in the United States in 2004. To learn more about what precautions producers should take, or for more information, click here to see the Delta Farm Press story.
Posted: 09/09/09
