Features Desiccants Seed & Chemical
Dry bean dry-down product watch for 2012

Fruits of research – since the December 2008 scare when Japan detected glyphosate residue in dry edible beans from Ontario – are starting to ripen. Months after Japan detected residues above the maximum allowed by their regulations, Canada’s dry bean industry took steps to address the problem. Studies began in 2009 in Ontario, to be followed in Manitoba and Alberta. Temporary minor use registrations for new products that could become pre-harvest aids were obtained.

Bean growers in all three provinces can look forward to the first real results from crunching research information later in 2012, in time for pre-harvest planning. The final report is expected in 2014.

The four-year study is headed by University of Guelph (Ridgetown) scientists, Chris Gillard and Peter Sikkema. They are working with cranberry and navy beans for the Ontario study at the Huron
research station.

On the Prairies, University of Manitoba professor Rob Gulden is participating in the project, with parallel field studies at Carmen using pinto beans. The AAFC center at Lethbridge is testing performance effects on small red beans.

Products in the study are Reglone, Aim EC (FMC Corp), Eragon (BASF Canada), Ignite (Bayer CropScience) and Valtera (Valent). Each is being applied at two or three rates and compared to the full label rate of glyphosate. Each has been applied alone, and in a tank mix with glyphosate.

Gillard says the new products are faster-acting for bean dry-down, generally. Results were not available for residue tests.

Dry-down options
Aim EC was registered in 2007 for weed control in pre-planting burndown and as a harvest-aid application in many crops, including dry beans. It contains carfentrazone-ethyl. Prairie bean producers can find the active ingredient in CleanStart, marketed by Nufarm Agriculture. CleanStart is a combination of glyphosate and carfentrazone
for burndown.

Valtera was registered in 2009 for pre-emergence weed control in soybean and for dry bean desiccation, for use on its own or as a pre-plant tank mix with glyphosate. It uses a Group 14 mode of action. The active ingredient is flumioxazin, registered in 2009. It is available across Canada. 

Eragon was registered in 2010 for burndown of broadleaf weeds, alone or as a tankmix with glyphosate for faster burndown, and as a pre-harvest aid for soybeans and dry bean crops. It is only registered in Eastern Canada.

Eragon contains a new BASF active ingredient, saflufenacil, with both contact and systemic properties. It is marketed as Kixor technology.

In 2011, BASF released Kixor technology for Western Canada and the northern Great Plains under two new labels. It is marketed as Heat herbicide on the Prairies and as Sharpen herbicide south of the border.

Faster dry-down
The project has several purposes for the dry bean industry, Gillard says. It is gathering information on the effects of current and new desiccants, on the effects of timing, rates, tank mixes, seed quality and seed yield as well as herbicide residues in the seed. Other aspects of the study include effectiveness on weed escapes, newly emerged weeds and environmental impact.

The objectives of the research project are to: provide uniform and rapid dry-down of dry beans, produce minimal herbicide residue levels in seed at harvest, have zero impact on seed quality and yield, provide effective control on weeds typically found in dry bean production areas and have low environmental impact.

In the preliminary Ontario work during the first two years, Gillard says, both pod and stem dry-down was slowest with glyphosate.

Alberta and Manitoba desiccant research began in 2010, but Alberta had major losses due to spring weather and Manitoba had fall conditions that were unusually late and wet. The first full season in Alberta was only completed in late 2011, and the Manitoba trials are waiting a closer-to-normal year for comparisons.

From the preliminary results, some strong activity is being measured in several of the new harvest-aid products. However, tank mixing with glyphosate may still be necessary to provide a high level of crop desiccation and adequate control of weed escapes. Results of residue testing were not available.   

“The industry needs to find a desiccant that does not have any residue issues so that, when we export, it does not become an issue,” says Dennis Lange, Manitoba provincial soybean specialist.
The primary registered desiccants are Reglone and Aim. Glyphosate is the most commonly used pre-harvest weed control product.

“Not everybody uses a desiccant. Typically, they’re a pre-harvest tool that is used where it is needed. If a farmer has a weedy field as harvest time comes, and he wants to improve the quality of his beans, he’ll choose one of those products to aid in the harvest process and get better quality,” Lange says. 

Improved outlook
The new management information for dry bean growers promises to be helpful when it becomes available later this year, says Alvin Klassen, Manitoba dry bean buyer for SaskCan Pulse Trading Company.

“I think there’s a place for new products. I also have continued to encourage the use of glyphosate, appropriately, on the dry bean crop,” he says. “Glyphosate is cheap. We have used glyphosate for a lot of years on dry beans, and it’s been relatively successful. The key is to apply it when the crop is at the stage of maturity where the beans themselves do not uptake residues of the chemical.”

Manitoba can produce 140,000 acres of dry beans in most years, successfully. Sometimes, frost comes before the beans have matured inside the pods. The production risk can be cut short by a quick treatment with a fast-acting harvest aid, but the product and the timing need to be right.

If there is a risk of frost damage, Klassen says, contact an agronomist or a bean buyer, and get a second opinion before doing an early treatment to stop crop growth.

"Get that opinion from them. That’s huge,” Klassen says.

March 1, 2012  By John Dietz