Establish early-season protection for top yields

NEW ORLEANS — Providing a solid source of protection that helps soybean plants emerge with more vigor and uniformity sets the foundation for higher yield potential at season’s end.

Dale Ireland, Syngenta Seedcare technical product lead, stressed the importance of early plant establishment at the company’s media summit.

“Ultimately what we’re looking for from a seed treatment is not just to get the seed to germinate, but to have an established plant stand as well as it can that basically represents the genetic potential of that corn or soybean,” Ireland said.

“We can impact our yield potential very early on either by not using a seed treatment on our soybeans or using the wrong seed treatment that maybe doesn’t focus on the important aspects.”

When soybean plants emerge with more vigor, they have improved root structure and efficiency to help plants absorb more nutrients and moisture.

Early-season vigor also provides a faster speed-to-canopy, which helps reduce weed competition and encourage greater potential yield, and faster plant establishment provides for greater opportunity to outgrow both biotic and abiotic stressors.

Costly

Thirty-six university Extension plant pathologists recently published a survey that found U.S. growers lose over 47.2 million bushels annually in soybeans with seedling diseases, including pythium, and about 25.36 million bushels are lost to phytophthora alone.

“A seed treatment is something that’s extremely important to making sure you have as much of that plant stand established and as much genetic potential the first two to four weeks of that germinated seed’s life is maximized,” Ireland said.

“That’s what a good fungicide/insecticide seed treatment does. By protecting against these early losses, you are protecting against the potential loss of final yield. You can limit your final yield in those first few weeks after planting by either not using a seed treatment or the wrong seed treatment.”

Primary Culprits

Pythium and phytophthora kill seedlings and leave the remaining plants compromised.

Rhizoctonia and fusarium nibble at the roots reducing root efficiency with moisture and nutrient uptake, especially when the plants are under drought stress.

Early-season insects can feed on soybean seedlings causing plant injury, stunting, delayed emergence or stand loss. For example, cumulative consumption of seedling shoot tissue by an adult bean leaf beetle can reduce yield by 12%.

A seed treatment that includes an insecticide helps protect and stabilize the established plant stand.

Environment-Driven

Pathogens are driven by weather and soil conditions. Cooler, wetter weather is conducive for pythium and sudden death syndrome.

“That type of weather encourages those diseases because you have slower growth and develops a greater opportunity for infection of the root system and the plant growth rate is slower which allows more infection,” Ireland said.

Phytophthora can be an issue in warmer soil and wetter conditions. Phytophthora and pythium both require moisture to be in that soil pore space for infection to occur.

“Seed treatments can protect against any of these no matter what the environment,” Ireland said.

Under drier conditions, fusarium and rhizoctonia are typically more of an issue.

“All of these pathogens are present at any given time in an agricultural soil. There are probably five to 10 different pythium species in any given pint of soil. It would depend on where you are north to south, what your cropping rotations are and what species dominate,” Ireland said.

“If you’re in Minnesota or Arkansas, those pythium species that predominate and are virulent and really problematic with corn and soybeans are going to vary, but I assure you they are present.”

Insecticides

An estimated 80% to 85% of U.S. soybeans have seed treatments and some also include an insecticide.

“When you do include an insecticide not only do you have the direct impact on insects in the soil, but also above-ground protection,” Ireland said.

“Within our products we’re using Cruiser, which is a thiamethoxan, a neonicotinoid class insecticide that’s been used for many years and highly successful. It has a unique characteristic beyond just its killing of seed-attacking and seedling-attacking insects.

“It also has a documented vigor effect. This is something that we were granted a patent on that enhances above- and below-ground cell growth. We know that plant growth comes from basically larger cells and more cells.”

The components of plant growth are additional cells, or each cell is larger.

“When you have different concentrations of Cruiser within a developing plant, as you increase the amount you increase plant growth rates under stress. Heat stress, or excessive and drier moisture stress are situations where a plant would normally cease to grow,” Ireland said.

“For example, in extremely dry weather or a salty condition, we know that when plants are treated with Cruiser they continue to grow longer in those conditions before they shut down and begin to die.

“So, not only does it help manage insects, but it also can help manage the growth rate under plant stress and it can get the plant up out of the ground under conditions that maybe it would be slower doing under cool weather for instance. That’s also going to help manage weeds because with quicker canopy development.”

Pythium Control

Picarbutrazox, a novel fungicide with a new mode of action, was launched into the market five years ago and provides robust protection in controlling pythium.

Syngenta received U.S. registration of Vayantis last year, a fungicide seed treatment containing PCBX.

“Pythium is the first seedling disease that most seeds or seedlings ever encounter and the first disease that may actually have a negative impact on a germinating seed. It can either eliminate the seed or seedling and reduce stand or if a plant does emerge and starts growing that is infected with pythium will be less thrifty with a compromised root system,” Ireland said.

Newest Offering

Syngenta introduced CruiserMaxx APX soybean seed treatment with PCBX in early 2022 that provides protection against early-season insects and diseases, including pythium and phytophthora.

Ireland showed trials comparing various seed treatments.

“In any given replicated trial, CruiserMaxx APX is among the top two in uniformity. It’s the consistency that we see when we add PCBX to that seed treatment. It has multiple effective modes of action,” he said.

“We know from our herbicide research that you need to have multiple modes of action to get durability, consistency and predictability. CruiserMaxx APX consistently delivers more plants, more uniformity and more yield potential.”