facebook_pixel

For better nematode control – Know Your Soil Types

Every year, cotton growers face two invisible pests that strike without warning, leaving rows of stunted, withered plants. The root knot and reniform nematodes are among a cotton grower’s most devastating enemies. Because they do most of their damage at the roots, they can destroy entire rows of young cotton plants before growers realize they have a problem. In fact, both species of nematodes together cause average losses of over 2% of the total U.S. cotton crop every year, valued over $100 million.

But controlling these nematodes poses a number of dilemmas for growers. Do they use a soil fumigant or spread nematicide on the soil surface? Do some areas need more treatment than others? Because each species prefers a different soil type, and some populations are more intense than others, treatment decisions can be both complicated and costly. Scouting the field by taking soil samples to find those populations is time intensive, and lab analysis of those samples is expensive. Conversely, applying a soil fumigant or a surface nematicide can reduce profits if the grower applies the wrong nematicide or an inaccurate amount.

Several researchers say that the key to nematode management may lie in the soil preference of each nematode species. Since root knot nematodes prefer sand, while reniform nematodes cluster in silty loam, finding the soil types present in a field may help predict locations where nematode problems will occur. To do that, researchers are testing electrical conductivity (EC) systems that analyze soil texture. (A popular example of an EC system is the Veris cart from Veris Industries.) From that analysis, soil-type maps are created.

Louisiana State University nematologist Charles Overstreet uses the maps to identify which places in a field are most likely to house root-knot and reniform nematode populations. “The lower the reading, the more sand in the field,” Overstreet says. “The higher the number, the more clay you have. Once you have clay, you don’t have as many problems with nematodes.”

The maps provide Overstreet and his team – GIS expert Maurice Wolcott, entomologist Gene Burris and plant pathologist Boyd Padgett – with clues about why some areas of the field were unproductive even with nematicide treatments.

“Growers assume the areas of low yield are those where the nematodes are,” Overstreet says. “But low yields may be just from other soil problems, or they may be from nematodes.”

The maps help Overstreet’s team create “management zones” based on soil type. These zones indicate where nematicide may be needed, and where it won’t have any benefit.

USDA soil scientist Dana Sullivan has had similar results in Georgia, where she and University of Georgia researchers Calvin Perry and George Vellidis, Extension Agent Keith Rucker and doctoral student Brenda Ortiz have been testing electrical conductivity measurements since 2005 to locate “hot spots” of root knot nematodes. They use the technology to create homogeneous zones by soil type and other geological variables such as topography and slope.

“Electrical conductivity measurements provide an important key to delineating areas most likely to have high populations of nematodes,” Sullivan says. “For the fields that were not completely infested, we may be able to tell growers, ‘If your field is going to have problems, it is most likely to be here.’”

What is N-Hibit?

The active ingredient in N-Hibit Seed Treatment is harpin protein, which is produced by disease-causing bacteria that attack plants. N-Hibit does not contain pathogens, but the presence of harpin protein turns on internal plant signals that activate natural self defense and growth systems as though the plant was under attack.
Harpin proteins do not enter the plant. They bind with the plant’s external harpin protein receptors, which are present on seed as well as foliage. After binding, the harpin proteins harmlessly disintegrate.
In cotton, according to data from Plant Health Care, Inc., marketers of N-Hibit, growth responses with N-Hibit typically produce increases in root volume and length, plant weight, overall plant vigor and nodes per plant.
The company says N-Hibit complements other nematode management tools.

While using soil EC as a flag to point to potential nematode management zones is a good first step, simply having soils that are favorable for nematodes is not the whole picture. The next questions are: Are nematodes present in these zones? And are the population densities high enough to justify the expense of a nematicide?

Those questions are currently driving the research into this technology. Sullivan’s team is beginning this year to evaluate nematicide rates in each zone. Overstreet, who began testing the EC system for nematode management in 2001, divides the management zones into “verification strips,” half treated with a soil fumigant, and half left untreated as a control area. The strips help validate not only the presence of nematodes in a zone, but also that the pests are the primary cause of any crop loss.

“We still don’t know where the transition zones are; that’s where the verification strips come into play,” Overstreet says. “Some farms we worked with had four or five textures in a field; that makes it very difficult to break it down without knowing where the textures change.”

Captions (3):

Stand damage from the reniform nematode is often
misidentified.

As the name implies, root knot nematodes cause knotty galls
that interfere with moisture and nutrient uptake.

Example of nematode data from a field, broken down into 4 classes.

Leave a Reply

Disease Control / Nematodes Stories
Disease Control / Nematodes

Be Ready to Fight Diseases in Cotton

June 23, 2017

Add bacterial blight to the list of diseases that Georgia cotton growers should be prepared to fight.

Disease Control / Nematodes

CSI AgriLife: Working to Solve a New Blight Mystery

March 10, 2017

Dr. Terry Wheeler and her Texas A&M AgriLife pathology colleagues are working to solve a mysterious problem thought to have been resolved 40 years ago.

Disease Control / Nematodes

Options for Farmers Battling Cotton Root Rot

January 17, 2017

Cotton root rot disease continues to be a major threat to Texas cotton, but there are options available to help farmers fend off potential threats or lessen the potential economic hardship.

Disease Control / Nematodes

Nematodes Can Survive Winter

December 28, 2016

Just about every crop has its nematode challenges. And many of our winter weeds are excellent overwintering hosts.

Disease Control / Nematodes

Reviewing Bacterial Blight in Georgia Cotton

September 30, 2016

Over the past two growing seasons, bacterial blight has been more visible in Georgia’s cotton than it has been in a number of years.

Disease Control / Nematodes

Spotting (and Managing) Target Spot

August 23, 2016

Target spot may never be a major problem in Mid-South cotton. But, as seen this year, growers need to watch for it under the right field conditions.

Disease Control / Nematodes

New Webcast Focuses on Cotton Virus Detection and Treatment

November 2, 2015

A new webcast focusing on the detection and treatment of cotton viruses has been added to the Focus on Cotton online series from the Plant Management Network and Cotton Incorporated.

Around The Gin
Product News

Bayer Shares the Risk with Cotton Farmers

January 26, 2018

Bayer offers replant, crop loss and yield protection to growers who plant FiberMax and Stoneville cotton seed.

Product News

Americot Adds New Sales Support in GA, KS and TX

January 23, 2018

Americot has expanded its sales support team in Georgia, Kansas and the Rolling Plains of Texas.

Product News

Indigo Offers Premium for Indigo Cotton Production

January 9, 2018

Indigo Ag has announced a new program that offers significant price premiums for U.S. cotton growers who contract to grow Indigo Cotton.

Product News

New Bayer Varieties Focus on High Yield, Adaptability

January 5, 2018

Bayer releases five new FiberMax and Stoneville varieties for introduction in 2018.

Product News

New PhytoGen TRiO Guards Cottonseed Investment

January 3, 2018

New PhytoGen TRiO seed treatment helps provide early season protection for young cottonseed from diseases, insects and nematodes.

Product News

Americot Adds Seven to Sales, Research Teams

December 20, 2017

Americot has added seven new sales and research associates to the company’s staff across the Cotton Belt.

Product News

Seven New Varieties in Deltapine Class of 18

December 11, 2017

Seven new varieties – including five Bollgard 3 XtendFlex offerings – join the Deltapine product lineup as the Class of 18.

Product News

Special Roundup Ready PLUS Incentives for Arkansas

December 7, 2017

Monsanto is offering a special Roundup Ready PLUS Crop Management Solutions platform in Arkansas for 2018 for growers planting XtendFlex cotton and Roundup Ready 2 Xtend soybean varieties.

Latest News
Disease Control / Nematodes

Be Ready to Fight Diseases in Cotton

June 23, 2017

Add bacterial blight to the list of diseases that Georgia cotton growers should be prepared to fight.

Disease Control / Nematodes

Taking Control of Nematodes

June 8, 2017

Georgia producer Johnny Cochran found a system-wide solution to handle the formidable nematode threat on his operation.

Disease Control / Nematodes

Sweet Tooth Bacteria Tracked in Bacterial Blight

May 25, 2017

Thanks to a new discovery, researchers now may be better equipped to help Texas cotton farmers battle bacterial blight.

Disease Control / Nematodes

CSI AgriLife: Working to Solve a New Blight Mystery

March 10, 2017

Dr. Terry Wheeler and her Texas A&M AgriLife pathology colleagues are working to solve a mysterious problem thought to have been resolved 40 years ago.

Disease Control / Nematodes

Options for Farmers Battling Cotton Root Rot

January 17, 2017

Cotton root rot disease continues to be a major threat to Texas cotton, but there are options available to help farmers fend off potential threats or lessen the potential economic hardship.

Disease Control / Nematodes

Nematodes Can Survive Winter

December 28, 2016

Just about every crop has its nematode challenges. And many of our winter weeds are excellent overwintering hosts.

Disease Control / Nematodes

Reviewing Bacterial Blight in Georgia Cotton

September 30, 2016

Over the past two growing seasons, bacterial blight has been more visible in Georgia’s cotton than it has been in a number of years.

Disease Control / Nematodes

Spotting (and Managing) Target Spot

August 23, 2016

Target spot may never be a major problem in Mid-South cotton. But, as seen this year, growers need to watch for it under the right field conditions.

Disease Control / Nematodes

New Webcast Focuses on Cotton Virus Detection and Treatment

November 2, 2015

A new webcast focusing on the detection and treatment of cotton viruses has been added to the Focus on Cotton online series from the Plant Management Network and Cotton Incorporated.

Disease Control / Nematodes

Researchers Discover Link to Nematode Activity

September 30, 2015

Scientists at the University of Missouri and the University of Bonn in Germany have found a genetic link to a hormone that nematodes use for feeding.

Disease Control / Nematodes

Solving the Nematode Puzzle

August 27, 2015

Growers and consultants in Georgia are finding ways to help boost yields and profits in nematode-infested fields.

Disease Control / Nematodes

New Cotton Webcasts Focus on Seedling Diseases and Soil Fertility

April 29, 2015

Two new webcasts focusing on seedling diseases and soil fertility have been added to the Focus on Cotton online webcast resource.

Disease Control / Nematodes

Not All Boll Rot Caused by Bacterial Blight

October 31, 2014

Identifying the cause of boll rot in Mississippi this season is not a simple task.

Disease Control / Nematodes

Nematode Research on the Rise

October 30, 2014

Take a peek at the seed company pipelines, and you’ll notice a common theme – nematode control.

Crop Inputs

New Cotton Webcasts Focus on Irrigation and Foliar Disease Management

July 18, 2014

Two new webcasts focusing on crop protection and irrigation management have been added to the Focus on Cotton online webcast resource, developed by Cotton Incorporated and the Plant Management Network.