U.S. Nebraska corn fields hit by Goss's Wilt disease

U.S. plant scientists have found the debilitating disease Goss's Wilt in multiple corn fields across Nebraska, raising fears of yield loss in the No. 3 U.S. corn state.

The disease is not widespread at this time, but oozing leaves and leaf lesions have been noted on corn plants. Testing has confirmed the Goss's bacterial wilt and blight in corn samples received from south central and eastern Nebraska, according to University of Nebraska-Lincoln (UNL) researchers.

"It's too early to tell" how destructive the disease will be this season, Tamra Jackson-Ziems, extension plant pathologist with the UNL Department of Plant Pathology, said on Tuesday.

The disease, which weakens corn plants, can shave yields by up to 60 bushels an acre. It is not new to Nebraska, or the U.S. corn belt, but it is rarely seen this early in the season, said plant experts, who blamed recent storms and a history of disease for the infection.

High winds and hail can provide openings for bacteria, and wet and humid weather encouraged disease development.

The earlier the disease develops, the more it can reduce production. Fungicides are not effective on the bacterial disease.

"Development of the disease now on susceptible hybrids could have devastating impacts on yield if the disease continues to worsen in those fields," said a UNL report.

In addition to Nebraska, the disease has been found before in key producers Iowa and Illinois as well as in Kansas, Colorado, Wyoming, South Dakota, and Wisconsin.

Last year, Iowa was the top corn state with 2.4 billion bushels followed by Illinois with 1.9 billion and Nebraska with 1.5 billion.

Some biotech crop critics have claimed a connection between widespread spraying of the weed killer glyphosate on fields of genetically altered glyphosate-tolerant corn and the outbreaks of Goss's Wilt, saying the glyphosate makes corn plants more susceptible to the disease.

But biotech industry leaders dispute that notion and say they are working hard to engineer corn that resists the disease.

A 2011 report from Purdue University crop scientists said "despite the potential for herbicides to increase disease levels in certain plants," plant pathologists had not observed a widespread increase in susceptibility to plant diseases in glyphosate-resistant corn and soybeans.