August 29, 2005
From: Journalstar.com, 28 Aug 2005 [edited] <http://www.journalstar.com/articles/2005/08/28/business/doc430f9598bc993543945906.txt>

Asian soybean rust [ASR] has been confined to southern states this summer and likely won't affect Midwestern fields this year, experts said. Soybean rust causes premature leaf loss, leading to fewer bean pods, fewer seeds per pod and early maturity, all of which adds up to lost crop yield. It arrived in the southern United States from South America late in 2004, and reached as far north as Missouri.

"There is still a remote chance we could see it, but it's a very, very low chance," said Loren Giesler, a University of Nebraska extension plant pathologist. "If we see it in northern states, it'll be late enough in crop production that [it] won't damage yield."

ASR spores have actually been detected this year as far north as Wisconsin, Illinois, Missouri and Arkansas in spore traps set up by Syngenta Crop Protection, a private company, but ASR failed to infect plants there, Giesler
said. But there have been no confirmed cases of the fungus infecting plants this summer north of Atlanta. Still, because ASR is infecting soybeans in Georgia, Florida, South Carolina, Alabama and Mississippi, it could survive
another winter in the South.

That means ASR could spread northward next year if weather conditions are right, said Susanne Bissonnette, a soybean rust expert with University of Illinois Extension, and farmers are no less worried about a disease that
scientists are still trying to understand. "Just because we didn't have it this year -- yet -- means nothing about next week or next year," said Jeff Abbey, who grows about 800 acres of soybeans near Bloomington, Ill. Giesler
said there's no way to predict what happens next year.

"If we see rust spread to the west, in Mexico, Texas, or Central America, that will increase the chance of finding it in our region." If it gets cold enough far south enough this winter, that would limit spreading next year. Prevailing
winds can make the difference, he said. "We don't really know the exact reasons why it didn't balloon out and spread faster and farther," said Glen Hartman, a plant pathologist at the National Soybean Research Laboratory on the University of Illinois campus.

Part of the reason the fungus has been confined to the South may be because it survived only in Florida during the winter of 2004-5. "If the epidemic had started in Louisiana or the bottom part of the Mississippi Valley, I think there would have been more chance for it to move up," Hartman said.

Since it was first spotted in this country last year, there were no preparations for finding, tracking and battling the disease. The government and agriculture industry has spent millions to provide information to farmers and train them to hunt for rust. Researchers from Florida to North Dakota also planted sentinel plots, special fields that are closely monitored to help track the fungus. In Nebraska, there are 48 of those plots, Giesler said.

"I don't remember any other (crop) disease in history where we've had so much interest and training ahead of time," Hartman said.

Farmers remain fearful of a disease that can cost a lot to fight.

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[The possibility that Hurricane Katrina may exacerbate spread of ASR in the southern states may be a factor in the coming weeks. Given that ASR is widespread in those states and that kudzu is a perennial ASR host, the disease could be a problem for soybean growers in the 2006 crop season.

Link: <http://www.pioneer.com/usa/agronomy/soybeans/asian_soybean_rust.htm> - Mod.DH]

[see also in the archive:
Soybean rust, Asian strain - USA (FL): 1st report 2005 20050309.0693 Soybean rust, Asian strain - USA (GA) 20050429.1196 Soybean rust, Asian strain - Americas: alert 20050528.1476 Soybean rust, Asian strain - USA (GA) 20050505.1245 Soybean rust, Asian strain - USA (LA) 20050624.1769 Soybean rust, Asian strain - USA (FL) (02) 20050620.1731 Soybean rust, Asian strain - USA (AL) 20050715.2029 Soybean rust, Asian strain - USA (multistate)(03) 20050714.2005 Soybean rust, Asian strain - USA (multistate)(02): Florida 20050708.1938 Soybean rust, Asian strain - USA (multistate) 20050702.1868 Soybean rust, Asian strain - USA (GA)(03) 20050827.2531 Soybean rust, Asian strain - USA (AL)(03) 20050826.2528 Soybean rust, Asian strain - USA (AL)(02) 20050824.2496 Soybean rust, Asian strain - USA (SC) 20050818.2414 Soybean rust, Asian strain - USA (FL)(03) 20050815.2386 Soybean rust, Asian strain - USA (Multistate)(06) 20050808.2318 Soybean rust, Asian strain - USA (multistate)(05): susp. 20050806.2291 Soybean rust - USA (multistate)(04) 20050806.2289]