BASF research tour unveils tips for next growing season

New agronomic innovations to battle disease, pests, and weeds in corn and soybeans were revealed to farmers at a recent BASF crop research tour in Story City, Iowa. Here are some growing season management tips and products that caught my attention.

Tar Spot, Corn's Growing Menace

Discovered in Illinois and Indiana corn fields back in 2015, tar spot is an aggressive disease that can become endemic. As of this year, it has been reported in over 20 counties in Iowa. It is also fast-moving; the lesions overwinter and germinate before shooting its inoculum into the air, which can catch farmers by surprise, says Gary Schmitz, the Midwest Regional Technical Services Manager for BASF.

"It sneaks up on us; we think we're good. We don't realize maybe those plants have already been infected, and then we go out and spray, and it's already been infected," Schmitz says. 

The earliest farmers can usually see tar spot is in mid-to-late June, which can also coincide with early summer rains, tar spot’s favorite environment. It loves moisture, thrives in a humid climate, and only needs seven hours of leaf wetness to germinate.

However, Schmitz says that a longer residual fungicide is a handy tool for growers to have in their toolbox against vigorous disease, including frog eye leaf spots, leaf blight, and gray leaf spot.

"A fungicide application will manage it, just like many other foliar diseases," he says.

BASF's fungicides, such as Veltyma and Revytek are designed to lock in with the crop's waxy cuticle and slowly meter its active ingredients out as the crop grows.

"We get about 28 days of good residual," Schmitz says. "Typically, we've targeted Veltyma for corn and Revytek for soybeans, but they can be used on both crops."

The best time for an application is when corn is at tasseling but in bad years we may need to spray as early as the V12-V14 stage.

"We've been spraying our corn around that tassel which is the most consistent and usually gives us the best return on investment year after year," he says.

However, the fungicide effects will eventually end. The residual will no longer be in the plant four weeks after application.

Most of the time, growers can get away with one application, but that depends on weather and other environmental conditions, adds Schmitz.

Breeding +Technology = More Bushels

Genetic screening means better soybeans and yields, says Bill Backhaus, a agronomist with BASF. For the 2024 planting season, 11 new soybean varieties from the Xitavo line, a joint venture between BASF and Corteva, will be available for purchase to farmers. In company trials, most 2024 varieties have proven to have a 1.9-bushel increase and are herbicide resistant. Backhaus says breeders are working on the 2025 class of soybean genetics with exclusive germplasm.

Farmers in the United States will also now have access to BASF's newest digital farming tool, Xarivo-Field Manager, a mobile platform that provides farmers with real-time field-specific nutrient management, including detailed growth stages of crops, application timing, and dosing, along with maps.

Yuck, Corn Rootworms

Corn rootworms are a billion-dollar pest to the industry. The western and northern corn rootworms are building resistance to BT corn traits. Most of the time, the growing pressure stems from mild winters that can extend the life cycle of the worms.

Recently, BASF introduced Nurizma, an insecticide, to the market as a new mode of action to eliminate corn rootworm larvae. One of the active ingredients is broflanilid of the irack classification of group 30, which is found in seed treatments for wheat to prevent wireworms from destroying seed.

Kurt Maertens, technical service representative with BASF, says in the seed treatment — broflanilid blocks the worm's neuron transmission, causing convulsions that kill the worm. However, the ingredient will also have a parallel effect on corn rootworms.

"This little bugger has been able to overcome all of our management options relatively fast if you think about it over the years — to the traits, to our crop rotation, even to the insecticides we use," he says. 

Farmers can use Nurizma, in-furrow at planting with their starter fertilizer, and handling the product is also safer, says Maertens.

Along with using a soil insecticide, growers are adapting their management for the pest with crop rotation, but worms have still been able to wiggle their way into crop rotation.

"What happens is that the females will mate with the males in the corn, but then they fly to soybeans, eat on soybeans, and lay their eggs in the soybean field," adds Maertens.

Maertens advises growers to rotate corn fields to soybeans or a forage crop once every 3 to 5 years to break up that cycle.

Additionally, he says farmers need to be scouting fields, setting up traps, digging some roots, and adding soil insecticide. 

Fighting Weeds

As weeds stack up their defenses against herbicides, farmers are increasing their spending because of the building resistance, which has been caused by attempts to counter pesky weeds with different products.

A 6-inch-tall weed can impact almost a 7% yield loss to crops, says Nate Quam, a technical service representative with BASF.

"We don't want to see any water hemp sticking up above those soybeans in August, or at least that's most people's expectations," says Quam.

Surtain, BASF's new herbicide, can give farmers eight weeks of residual control of almost 80 grass and broadleaf weeds, including stubborn Palmer amaranth and waterhemp.

The herbicide uses a dry encapsulation, which means it can be used in typical spraying systems, including nozzles. Adding a residual with that post-application, during pre-and early post-application of V1 corn — that second residual shot can improve a field's performance — giving it a 98% control against weeds. 

"If you're driving down a gravel road, a field of 98% control will look perfectly clean. So that's why we do the programs we do, we want to start with that good solid pre and we want to come back with a layered residual," Quam says.

Spraying an excellent solid pre- herbicide can also give farmers flexibility on a post-application if the weather doesn't permit it. Using a residual post application also helps hold back weeds, adds Dan Waldstein, a crop protection specialist with BASF.

Weed resistance also plagues many crops, so Waldstein says growers should consider including a layer residual when a returning to the field 25-35 days post application, as it can help the weeded seed bank.

"The priority's always going to be planting, but it's hard, especially in a compressed season where there's not a lot of days for good planting, and then trying to catch up with spraying can be challenging. We can alleviate some of that by spraying even before planting, but it can be challenging," says Waldstein.

BASF has also reformulated its Liberty 280 herbicide; the product title name will be introduced this summer, says Mark Storr, with BASF. The new herbicide is advanced with solvents that help with antifreeze and make the thawing process in the bulk tank easier.

Storr says the best tips for spraying herbicides with successful outcomes are spreading at the correct rate per acre, in sunny weather conditions, and spraying when the weeds are 3-4 inches tall.