Soybean Vein Necrosis Virus Identified in Iowa

Soybean vein necrosis virus (SVNV) was first confirmed in Iowa last season. Last year we did not see SVNV until August. This past week we identified SVNV in several locations in Iowa. It is not known yet if earlier symptoms may increase chances of yield loss. We will continue to monitor and provide updates

Risk of Sudden Death Syndrome Increasing with Rains

One thing we have learned from outbreaks of sudden death syndrome (SDS) in years past is that this disease likes it wet. Last year we wrote about the risk of SDS increasing with the early season rain. But at the end of the article we threw in one caveat — soybeans were planted very late in the season, which reduced the risk of SDS developing. And after we published the article, the rains essentially stopped. Fast forward to the end of the 2013 season -- we still had some SDS in parts of Iowa in 2013, but it was not as nearly as bad as it could have been

Soybean Rust Overwintering in the South

Despite soybean rust infecting fields in Iowa last fall, the pathogen needs to retrace its steps to get back to Iowa in 2008. The first critical step is for the pathogen to survive somewhere over the winter in places like Florida, Texas or Mexico. An extensive study on the survival of soybean rust was completed in Florida by W. Jurick, J. Marios, D. Wright and P. Harmon

Soybean Diseases Starting to Wake Up

After taking much of the growing season off, soybean diseases are finally starting to wake up and make a bit of noise

Weed Identification Guide Available Electronically

The popular Weed Identification Field Guide is now available electronically as an e-book and, for the first time, downloadable on iPad. The publication is distributed by the Iowa Soybean Association (ISA) and Iowa State University (ISU) Extension and Outreach. Pioneer Hi-Bred, a DuPont business, has sponsored the capability for users to download the electronic versions for no charge

Fungicides: QoI fungicides

Quinone outside inhibitor (QoI) fungicides include three fungicide families, the well-known family of strobilurins and two new families, represented by fenamidone and famoxadone. QoI fungicides approved for, or in review for, use on field crops in Iowa include strobilurins azoxystrobin, pyraclostrobin and trifloxystrobin, and famoxadone. These fungicides are used on cereal grains, corn, and soybean as well as many other crops in Iowa, such as fruit trees, small fruit, vegetables, and turf

2009 Soybean Rust Summary

Soybean rust once again did not make it to Iowa in 2009, but it wasn’t from a lack of trying. Rust was found early in Louisiana and eventually was found at high levels throughout the Southeast. These – overwintering finds and high levels of inoculum in the South – are two prerequisites for rust getting to Iowa

Soybean rust update

Any daylily or tulip enthusiasts may be bemoaning the recent cold snap that left many early-greening plants very sad across much of Iowa. Well, cold weather can be our friend as well. On April 7 and 8, a cold front pushed as far south as the Florida Panhandle, and kudzu growth was slowed or knocked back from this record-breaking frost. The freezing temperatures on the rapidly growing kudzu in this area could reduce the buildup and potential spread of soybean rust for several weeks. This frost came much later than their March 15 frost-free date

End of Season Soybean Rust Update

Following the pattern of 2010, soybean rust never really got off the starting line in 2011. As of mid-October, soybean rust has been found in two Georgia counties, seven Florida counties and one Louisiana county in the continental United States. The disease was also found in parts of Mexico and Puerto Rico earlier this year; there is a recent report (early October) out of Tamaulipas, Mexico (Figure 1)

Soybean rust: A year in review

During the 2005 and 2006 growing seasons, soybean rust was not a threat for Iowa soybean growers. This year was a different story, as soybean rust was established fairly early in the season in Texas and Louisiana creating the potential for soybean rust to get to Iowa during the growing season. Thankfully, soybean rust was not found while soybean plants were in a vulnerable stage; however, soybean rust was found in a field in Dallas County, Iowa, on Tuesday, September 25, 2007. Since the initial find, soybean rust was confirmed in 13 additional counties in Iowa (Figure 1)