Asian soybean rust has been found outside Florida for the first time since the Deep South was struck by a record-breaking Easter weekend frost. It was detected Tuesday in a weed patch west of New Orleans, La.
"Asian soybean rust has been observed on kudzu in Iberia Parish," said a state report filed Friday through the official rust web site of the U.S. Department of Agriculture. "The incidence and severity are low, but the presence of Asian soybean rust (in Louisiana) so early in the season (53 days earlier than 2006) is of major concern.
Heavy rains, conducive to development of the moisture-loving plant fungus, fell across Louisiana last weekend.
"Continued scattered showers are predicted through the next week," said the Louisiana state rust report. "Environmental conditions are very good for Asian soy bean rust development."
The Louisiana outbreak is thought to be the only infection currently existing outside of Florida, where six counties are known to harbor the airborne disease.
"No active sites of soybean rust have been reported in Alabama, Georgia, or Texas," noted USDA in its national soybean rust commentary. "Scouting efforts have intensified in the South, especially on kudzu and on soybeans in some southern states. Soybean sentinel plots continue to be planted throughout the soybean belt."
The latest rust dispersal forecast - issued Wednesday by USDA - said clouds, showers and easterly winds produced by Tropical Storm Andrea "will increase the risk of soybean rust spread into southern Georgia and along eastern portions of the Florida panhandle. However, the limited availability of spores due to a relatively quiet season thus far, will slightly diminish the risk of spread into Georgia."
Soybean rust is one of the world's most virulent plant diseases, capable of causing severe yield losses through premature defoliation, unless quickly countered with chemical fungicides. The pathogen was found in more than 200 U.S. counties during 2006, but failed to cause significant damage, due to delayed development caused by spring drought in the Deep South.
Source: Dow Jones newswires