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Last County In Iowa Found Infested With Scn, Greg Tylka, Brian Lang Jan 2017

Last County In Iowa Found Infested With Scn, Greg Tylka, Brian Lang

Integrated Crop Management News

More than 100 fields throughout Iowa were surveyed for the presence of the soybean cyst nematode (SCN) in 2016 in a project sponsored by the ISU Soybean Research Center and the Iowa Soybean Association (ISA). Soil samples were collected by Iowa State University Extension and Outreach field agronomists and ISA staff and interns and sent to the ISU Plant and Insect Diagnostic Clinic for processing.


Performance Of Scn-Resistant Soybean Varieties In Iowa In 2016, Greg Tylka Dec 2016

Performance Of Scn-Resistant Soybean Varieties In Iowa In 2016, Greg Tylka

Integrated Crop Management News

Soybean varieties that are resistant to the soybean cyst nematode (SCN) are essential tools for managing the pest. Resistance to SCN requires multiple genes, and soybean varieties bred to be resistant may not contain all of the resistance genes necessary to provide maximum nematode control. Consequently, SCN control can vary greatly among resistant soybean varieties, just as yield.

Iowa State University evaluates the SCN control and yield of SCN-resistant soybean varieties in field experiments conducted throughout Iowa annually. The effort is supported, in part, by soybean checkoff funds from the Iowa Soybean Association.


What’S The Situation With Scn In Your Fields?, Greg Tylka Oct 2016

What’S The Situation With Scn In Your Fields?, Greg Tylka

Integrated Crop Management News

The soybean cyst nematode (SCN) is capable of causing serious yield loss on soybeans every year and is widespread throughout Iowa and much of the Midwest. In the “good ole days,” a farmer was “good to go” with SCN management if he or she knew what fields were infested with the nematode and then grew SCN-resistant soybean varieties in rotation with the nonhost crop corn. Nowadays, though, things are a little more complicated.

The fact is, your SCN numbers may be building up unbeknownst to you. This buildup can go unrecognized because a soybean crop often does not appear stressed ...


More Scn-Resistant Soybean Varieties Than Ever, But Diversity Of Resistance Is Lacking, Greg Tylka Oct 2016

More Scn-Resistant Soybean Varieties Than Ever, But Diversity Of Resistance Is Lacking, Greg Tylka

Integrated Crop Management News

Nearly 40 years after its discovery in the upper Midwest, the soybean cyst nematode (SCN) continues to be a highly damaging pathogen of soybeans in Iowa and surrounding soybean-producing states. SCN is most damaging in hot, dry growing seasons, but yield losses of 10% to 25% or more can occur in years when temperatures are moderate and rainfall is average or above average. Growing SCN-resistant soybean varieties can slow the build-up of SCN population densities (numbers) in the soil and produce profitable soybean yields in SCN-infested fields.


2015 Evaluation Of Commercial Seed Treatments On Soybean At Three Locations In Iowa, Alison E. Robertson, Mauricio Serrano, Stith N. Wiggs Apr 2016

2015 Evaluation Of Commercial Seed Treatments On Soybean At Three Locations In Iowa, Alison E. Robertson, Mauricio Serrano, Stith N. Wiggs

Integrated Crop Management News

In 2015, 13 currently available commercial seed treatments were evaluated at three locations in Iowa. Seed treatments that reduce the risk of seedling diseases, soybean cyst nematode (SCN) and sudden death syndrome (SDS) were included in the trial. The goal of the trials is to provide information of the effect of commercial seed treatments on stand count, disease incidence and severity, and yield of soybean. Funding is provided by Iowa Soybean Association.


Research Shows Extra Cover Crop Growth Prior To Soybeans Provides Benefits, Daren S. Mueller, Michael J. Castellano Mar 2016

Research Shows Extra Cover Crop Growth Prior To Soybeans Provides Benefits, Daren S. Mueller, Michael J. Castellano

Integrated Crop Management News

This study, funded by the United Soybean Board (USB), was conducted to understand the potential for cover crops to perform in a corn and soybean rotation, and to collect data on the performance of cover crops in those rotations in relation to the timing of termination.


Managing Two Soybean Pests To Optimize Yield, Erin W. Hodgson, Gregory L. Tylka, Aaron J. Gassmann Feb 2016

Managing Two Soybean Pests To Optimize Yield, Erin W. Hodgson, Gregory L. Tylka, Aaron J. Gassmann

Integrated Crop Management News

Soybean cyst nematode (SCN) and soybean aphid (SBA) are important soybean pests in the north-central region. Soybean varieties with host plant resistance for SCN (PI88788) and SBA (Rag1) can suppress pest populations and subsequently protect yield. In addition, seed treatments are becoming widely adopted and now can include a nematacide, fungicides and insecticide. Combining host plant resistance with seed treatments could potentially further protect yield. This article summarizes a 3-year research effort, funded by the soybean checkoff through a grant from the Iowa Soybean Association, that evaluated interactions among these two pests, host plant resistance, and seed treatments.


Scn Resistance Continues To Pay Twice In 2015, Gregory L. Tylka Jan 2016

Scn Resistance Continues To Pay Twice In 2015, Gregory L. Tylka

Integrated Crop Management News

Resistant soybean varieties are a vital tool for managing the soybean cyst nematode (SCN). These soybean varieties must contain several genes to be fully resistant to the nematode. Not all SCN-resistant varieties contain a full set of resistance genes. Consequently, SCN-resistant soybean varieties can vary greatly in their agronomic performance and the SCN control that they provide.


Mid-Season Soybean Diseases Out In Full Force: How To Send A Sample To Isu Diagnostic Clinic, Laura C.H. Jesse, Daren S. Mueller Jul 2014

Mid-Season Soybean Diseases Out In Full Force: How To Send A Sample To Isu Diagnostic Clinic, Laura C.H. Jesse, Daren S. Mueller

Integrated Crop Management News

Soybean samples have been arriving almost daily at the ISU Plant and Insect Diagnostic Clinic this year. Early season problems were primarily damping off diseases and problems with herbicide carryover or sometimes a combination of the two.


Northern Leaf Blight Prevalent In Iowa, Alison E. Robertson Jul 2014

Northern Leaf Blight Prevalent In Iowa, Alison E. Robertson

Integrated Crop Management News

Northern corn leaf blight (NCLB) has been reported in numerous fields in Iowa. Most of the reports have come from central and western Iowa, but since the pathogen that causes this disease is spread by wind and rain, the disease could be more widespread.


More Than 800 Scn-Resistant Soybean Varieties Available To Iowa Growers, Gregory L. Tylka Nov 2010

More Than 800 Scn-Resistant Soybean Varieties Available To Iowa Growers, Gregory L. Tylka

Integrated Crop Management News

Soybean varieties that are resistant to the soybean cyst nematode (SCN) are extremely important for managing this damaging pest. In general, SCN-resistant soybean varieties yield greater than susceptible varieties in SCN-infested fields, and resistant varieties keep SCN population densities from increasing, which ensures profitable soybean production in future years.


When To Sample For Nematodes On Corn - It Depends, Gregory L. Tylka Oct 2010

When To Sample For Nematodes On Corn - It Depends, Gregory L. Tylka

Integrated Crop Management News

A recurring question often asked concerning plant-parasitic nematodes that feed on corn is, “When should samples be collected to check for these pests?” The answer depends on the details of each specific field situation. In most cases, fall sampling to test for nematodes that feed on corn is not recommended.


Towards A Successful Harvest: Stalk Rots And Standability Issues, Alison E. Robertson Sep 2010

Towards A Successful Harvest: Stalk Rots And Standability Issues, Alison E. Robertson

Integrated Crop Management News

It’s hard to believe the 2010 growing season is almost over. Most of the corn across the state is nearing or at black-layer, which means it is time to scout fields for stalk rots in an effort to evaluate standability and plan a successful harvest. Stalk rots are likely to be an issue this growing season. We have seen significant blighting of the leaves in the upper canopy predominantly from Goss’s wilt, northern corn leaf blight, gray leaf spot and anthracnose top dieback. When significant leaf blight occurs in the upper canopy, the risk of stalk rots increases ...


Good Harvest In Corn Should Help Manage Soybean Sds, Xiao-Bing Yang, Shrishail S. Navi Sep 2010

Good Harvest In Corn Should Help Manage Soybean Sds, Xiao-Bing Yang, Shrishail S. Navi

Integrated Crop Management News

This year is one of the worst soybean sudden death syndrome (SDS) epidemics since the disease was found in Iowa in 1994. Preliminary research data suggest that corn has much to do with SDS pathogen and there are things we can do about the disease as we begin harvest. Management of SDS should start when we harvest corn fields.


Video Offers Guidance For Coping With Soybean Sudden Death Syndrome, Alison E. Robertson, Leonor F.S. Leandro Sep 2010

Video Offers Guidance For Coping With Soybean Sudden Death Syndrome, Alison E. Robertson, Leonor F.S. Leandro

Integrated Crop Management News

As soybean sudden death syndrome (SDS) continues to ravage Iowa fields in one of the worst outbreaks in many years, Iowa soybean growers are increasingly worried about the damage the disease will cause, while others are unsure whether their plants have been infected. To help answer questions and offer guidance in managing the disease, Iowa State University has produced a video that explains why SDS is so severe this season; tells how to assess and manage SDS; offers practical advice growers can follow now to prepare for next year; and highlights new and ongoing ISU research on the problem.


Answers To Questions About Soybean Sudden Death Syndrome In Iowa 2010, Alison E. Robertson, Leonor F.S. Leandro Sep 2010

Answers To Questions About Soybean Sudden Death Syndrome In Iowa 2010, Alison E. Robertson, Leonor F.S. Leandro

Integrated Crop Management News

Sudden death syndrome (SDS) is now among the top four yield robbing diseases in soybeans. From 1999 to 2004, average losses in the U.S. were estimated at $190 million a year, and the disease is spreading and intensifying. SDS has been widespread and severe in Iowa this growing season, generating many questions of researchers. The most frequently asked questions are included in the following series of questions and answers.


Soybean Sudden Death Syndrome In A Flood Year - What To Do Next, Xiao-Bing Yang Aug 2010

Soybean Sudden Death Syndrome In A Flood Year - What To Do Next, Xiao-Bing Yang

Integrated Crop Management News

Soybean Sudden Death Syndrome (SDS) is widespread in Iowa. This year has had one of the worst epidemics since the disease was found in Iowa in 1994. Severely infested soybean fields can be found in every region in Iowa. It is easy to spot brown patches caused by SDS while you are driving the highways. Fields with large portions of premature defoliation can be found in early August.


Common, Weird And Unusual Spots Showing Up On Corn, Alison E. Robertson, Laura C.H. Jesse, Fanny Iriarte Aug 2010

Common, Weird And Unusual Spots Showing Up On Corn, Alison E. Robertson, Laura C.H. Jesse, Fanny Iriarte

Integrated Crop Management News

There have been several recent reports of leaf spots showing up on corn in addition to the eyespot and Goss’s wilt reported earlier this growing season. Some of these are expected – Northern corn leaf blight and gray leaf spot, but some such as southern rust are a little less common, and others are just weird.


Be On The Lookout For Soybean Diseases, Alison E. Robertson, Daren S. Mueller Aug 2010

Be On The Lookout For Soybean Diseases, Alison E. Robertson, Daren S. Mueller

Integrated Crop Management News

While this season is progressing much quicker than last year, one thing is remaining the same – lots of rain. With the rain, several diseases are starting to show up or are expected to show up during the next month.


Mid-Season Soybean Diseases: Scouting And Management, Xiao-Bing Yang Jul 2010

Mid-Season Soybean Diseases: Scouting And Management, Xiao-Bing Yang

Integrated Crop Management News

This is another unusual growing season, with a cool and wet spring followed by the hot and rainy summer. The cool weather that continued into the first week of July suddenly changed when a heat wave accompanied with rainy days arrived. The hot and wet final two weeks of July remind me of the subtropical weather in the Gulf Coast of Louisiana where I did my graduate study and where foliar diseases are a major issue in crop protection each year.


Check Soybean Roots For Scn Females, Gregory L. Tylka Jul 2010

Check Soybean Roots For Scn Females, Gregory L. Tylka

Integrated Crop Management News

The soybean cyst nematode (SCN) is widespread throughout Iowa and surrounding states, and as much as 40 percent yield loss can occur from SCN damage without symptoms appearing. Symptoms typically are not apparent when temperatures are moderate and rainfall is adequate to excessive during the growing season.


Nematodes Damaging Corn This Year?, Gregory L. Tylka Jul 2010

Nematodes Damaging Corn This Year?, Gregory L. Tylka

Integrated Crop Management News

Currently, there is considerable interest and continued discussion among growers, agronomists and university researchers about plant-parasitic nematodes that feed on corn. To find out if these microscopic worms are damaging a corn crop, soil and roots must be collected and sent to a qualified laboratory to determine which specific nematodes are present and at what population densities (numbers).


White Mold Mushrooms Show Up, Xiao-Bing Yang, Shrishail S. Navi, Xun Li Jul 2010

White Mold Mushrooms Show Up, Xiao-Bing Yang, Shrishail S. Navi, Xun Li

Integrated Crop Management News

Over the last 10 days the weather was favorable for the production of soybean white mold mushrooms in Iowa. Yesterday we visited fields near Clear Lake in north central Iowa with crop consultant Dan Muff and found abundant white mold mushrooms in a continuous soybean field, which had a closed canopy with wonderful growth. The density of the mushrooms was very high, 3 apothecia/square foot, and soybean plants are likely to be infected. The early showing in such a large number in this field was due to early planting, good growth and a higher number of sclerotia from last ...


Summary: Foliar Fungicide On Corn In Iowa (2007 – 2009), Daren S. Mueller, Alison E. Robertson Jul 2010

Summary: Foliar Fungicide On Corn In Iowa (2007 – 2009), Daren S. Mueller, Alison E. Robertson

Integrated Crop Management News

Data from corn fungicide small plot trials conducted by Iowa State University faculty and staff, and on-farm trials conducted by the Iowa Soybean Association On-Farm Network, the ISU Corn and Soybean Initiative and the ISU Northwest On-Farm research program were recently collated and summarized.


Summary: Foliar Fungicide On Soybean In Iowa (2006 – 2009), Daren S. Mueller, Alison E. Robertson Jul 2010

Summary: Foliar Fungicide On Soybean In Iowa (2006 – 2009), Daren S. Mueller, Alison E. Robertson

Integrated Crop Management News

We recently collated and summarized data from soybean fungicide small plot trials conducted by Iowa State University faculty and staff, and on-farm trials conducted by the Iowa Soybean Association On-Farm Network, the ISU Corn and Soybean Initiative and the ISU Northwest On-Farm research program.


Start Checking Soybean Roots For Scn Females, Gregory L. Tylka Jun 2010

Start Checking Soybean Roots For Scn Females, Gregory L. Tylka

Integrated Crop Management News

Soybean cyst nematode (SCN) is a serious pest concern for soybean every season in Iowa. Current SCN management options include soil-applied nematicides and resistant soybean varieties. All are implemented at the time of planting. However, effective scouting during the growing season is the key to successful, integrated management of SCN.


Characteristics Of Corn Left Standing Through Winter 2009-2010 In Iowa, Alison E. Robertson, Gary P. Munkvold, Charles R. Hurburgh Jun 2010

Characteristics Of Corn Left Standing Through Winter 2009-2010 In Iowa, Alison E. Robertson, Gary P. Munkvold, Charles R. Hurburgh

Integrated Crop Management News

Very wet conditions in October 2009 and early snowfalls in November resulted in several thousand acres of corn left standing through the winter in Iowa. Considering the grain quality issues that ended the growing season, concerns were raised regarding the quality of corn left standing over the winter.


Scouting For Soybean Seedling Diseases, Xiao-Bing Yang, Shrishail S. Navi Jun 2010

Scouting For Soybean Seedling Diseases, Xiao-Bing Yang, Shrishail S. Navi

Integrated Crop Management News

Seedling diseases are one reason to use seed treatment. Each planting season, different weather patterns result in different seedling disease problems. This planting season has been smooth in general and seedlings have emerged in many soybean fields. So far, disease risk is lighter than last year. We did, however, observe some light occurrence of seedling disease from production fields around the central Iowa. Damping-off was also found in our research plots. It is now time to check your soybean fields to determine if there are any seedling disease problems.


Sampling Strip Trials For Corn Nematodes, Gregory L. Tylka May 2010

Sampling Strip Trials For Corn Nematodes, Gregory L. Tylka

Integrated Crop Management News

Many people currently are asking how to collect nematode samples from strip trials of corn treated with new seed-treatment nematicide products. Avicta® Complete Corn and Votivo™ are the two products commonly being compared. Avicta® Complete Corn, which was widely available to corn producers for the first time in 2010, is a combination of the Avicta seed treatment nematicide (active ingredient abamectin), a seed treatment insecticide and three seed treatment fungicides. Votivo™ is a biological seed treatment containing the bacterium Bacillus firmus that will be available in 2011.


2010 Soybean Rust Update, Daren S. Mueller May 2010

2010 Soybean Rust Update, Daren S. Mueller

Integrated Crop Management News

This could be the world’s shortest ICM News article. It could simply read “soybean rust, meh”. But I will take some time to explain. We have identified three critical steps that must happen for rust to get to Iowa. They are (1) to survive winters somewhere in the south, (2) build up inoculum (spores) where survival occurs and (3) movement of these spores to fields further north and successful infection of soybeans in those fields. These steps may need to reoccur several times for rust to get to Iowa.