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Monday, Aug. 29, 2016

Now is the time to learn about soybean rust

Monday, December 6, 2004

PORTAGEVILLE -- Missouri farmers may have experienced record yields with the soybean crop this season, but with the discovery of Asian soybean rust in the area, agriculture officials are encouraging farmers to learn more about the fungus that can stunt plant growth and wipe out a large portion of their crop.

Last week the state Department of Agriculture announced the discovery of the disease in Missouri near Portageville, Caruthersville and areas close to the Arkansas state line.

"We're being cautious and the key thing is farmers just have to be knowledgeable about the rust, and know it works from the bottom of the plant and up," explained Grover Shannon, soybean breeder for the University of Missouri Delta Center in Portageville. "They'll have to get out in their fields and really look for it."

Shannon, who aided in locating the rust in New Madrid and Pemiscot counties, said Delta Center officials had to hunt in places that had any green leaves on the plants in order to collect the samples.

Missouri is the seventh state to find the soybean rust. Other states are Louisiana, Alabama, Georgia, Florida, Mississippi, Arkansas and (unofficially) Tennessee, Shannon noted, adding officials believe it blew into the United States with Hurricane Ivan.

"What's significant (about finding the rust in Missouri) is we're the most northern state that's found it," Shannon said. "Missouri is considered one of the more Midwestern states and about 80 percent of soybeans are produced in the Midwest with Illinois and Iowa being the top two soybean-producing states. So this is a real wake-up call for them."

However, one thing working in favor for the Midwestern farmers is if the soybean rust does return next year, it will be seen first in the southern states like Louisiana, Mississippi and Arkansas, giving farmers north of them a warning, Shannon said.

"Rust is a bad problem in places where they don't have frost, but we have frost (in Missouri)," Shannon said. "So if it kills out this year, then it will have to blow up from somewhere else next year."

Soybean rust is spread by wind-borne spores that can travel more than 1,000 miles. The fungus creates reddish-brown blotches on leaves that can weaken the plants and reduce yields.

The disease cost Brazilian farmers about $1 billion last year in control costs and crop losses, and some Asian growers have lost up to 80 percent of their crops. In the United States, the soybean crop is an $18 billion commodity ranked second only to corn.

Dr. Allen Wrather, a professor for the University of Missouri-Columbia at the Delta Center in Portageville, said there will be several opportunities for farmers to learn more about soybean rust.

For example, an informational meeting about soybean rust will be conducted Jan. 14 at the Clinton Building in Sikeston and Jan. 13 in Jackson; however times are not confirmed yet.

"There are a lot of groups -- several throughout the United States -- compiling information that will be a benefit to farmers when they're making decisions about managing pests next year," Wrather said. "A lot of groups will have their information prepared by mid-January, and it will be distributed in packets to farmers (at the meetings)."

Something farmers should know is currently there are no resistant varieties to Asian soybean rust, Wrather said, adding the only practice is to spray soybeans with fungicide.

"Decisions about which products to use and when to spray will depend on how the disease develops, which won't be known until later this summer," Wrather explained.

And if farmers have to use a fungicide next year, it will likely add more to cost to their production -- up to $20 an acre more, Shannon pointed out.

Although good cold weather this winter will help since the rust can't survive in those conditions, Shannon said the key to fighting soybean rust is early detection and using fungicide.

"Rust doesn't like temperatures over 90 degrees either. Our summer weather may be too hot for it. It has to have the right environment and right conditions to live," Shannon said.

To detect soybean rust, the Department of Agriculture advises producers to look for small abrasions on the lower leaves of their plants. The abrasions increase in size and change from a grayish color to a tan or reddish brown on the underside of the leaves. Although lesions are most commonly found on the leaves, they may also appear on petioles, stems and/or pods.

"Farmers will need to seek more information and be alert. The 'wait and see approach' will be necessary," Wrather encouraged.

Research is currently under way at the University of Missouri to develop a value-added soybean that is exclusively resistant to soybean rust. The plan is to use new technology to identify and deliver defenses to the Asian soybean rust and halt its development, according to the state Department of Agriculture.

Meanwhile Shannon said he's remaining optimistic.

"Our farmers are pretty educated and have been watching the progression of rust," Shannon said. "They know a lot about it and have heard a lot already. If it does return, I think they'll have their guns loaded and will know what to do."

For more information about soybean rust or the upcoming informational meetings, farmers should contact their county's extension offices.