Down, But Not Out

By Jason Jenkins, Mill Creek Communications

When the USDA National Agricultural Statistics Service released its annual Acreage report at the end of June, it came as no surprise that Missouri’s soybean acres would be down even further than what the agency had estimated just three short months earlier.

A lot had happened in those 90 days.

Above-average rainfall across the Show-Me State and historic flooding along both the Mississippi and Missouri rivers kept many fields inundated for weeks — or longer. For some, replanting did occur; for others, those hopes sank beneath the waters still covering their fields. Filing for prevented planting benefits became the only option.

By its best estimation, USDA determined that 5.3 million acres were planted to soybean in Missouri, down 9 percent or roughly 550,000 acres from 2018 — and a difference of 200,000 acres from what the agency stated in its Prospective Plantings reports in March. The percentage of acres planted to conventional soybean also fell — from 9 percent in 2018 to just 6 percent, which was the national average for the sixth consecutive year.

Both Robert Alpers of Prairie Home and Pat Hobbs of Dudley intended to plant conventional soybeans as a means of increasing their returns on investment in 2019. In Cooper County, Alpers selected an upland field near his home to plant his first conventional beans in 18 years. Hobbs chose a bottomland field in Stoddard County where he hoped a cover crop of cereal ryegrass would help with his early-season weed control.

He never got to find out.

“That field flooded and has stayed wet, so we couldn’t do anything with it,” Hobbs says. “Sot hat’s where our story with conventional beans ends this year.”

Though weather delayed his planting, too, Alpers’ conventional beans were closing the canopy by the second week of July.

“We had about 500 acres that we lost down in the river bottom, and most of that was going to beans,” Alpers says. “Everything up here on the hills looks fine, and now that the rows have canopied, that sure helps with the weed control. Those conventional beans are really starting to take off.”

The current chairman of the Missouri Soybean Merchandising Council believes the most critical aspect of managing his conventional soybeans has been the timing of herbicide applications, both pre-and post-emergence. After not being able to spray last fall due to wet conditions, he decided to apply a pre-emergent with his burndown application, then another pre-emergent at planting, followed by a post-emergent application.

“A lot of times, we were wondering if we were going to get it applied before the next rain came, but we were always able to,” he says. “We used all generics, so I really didn’t spend any more on chemicals for the conventional beans than I did with my LibertyLink beans.”

Flooding and wet conditions that delayed planting also have led to a number of early-season diseases, says Kaitlyn Bissonnette, University of Missouri Extension state field crops plant pathologist.

“It really didn’t matter if you were doing conventional or if you were doing GMO,” she says, noting that most (48 percent) of the Missouri soybean crop was reported to be in fair condition to start the second week of July.

“All of that rain and flooding really put us in this scenario where there are a lot of issues with stand and seedling disease problems.”

Water molds are the biggest early-season culprits, says the plant pathologist. Cold and wet conditions can lead to issues with Pythium, which causes seedlings to rot prior to emergence, die off suddenly after emergence and/or have weakened roots. Phytophphora is another pathogen that thrives in wet, warm conditions and can lead to soybean root and stem rot.

“With these diseases, you’re losing plants. A lot of times, the crop can compensate for lost plants, but when you lose too many, that ability is really diminished, and you start losing yield potential,” Bissonnette explains. “I wouldn’t be surprised to see a little bit of Phytophphora appear again in some of these fields that still may be a little bit saturated.”

While seed treatments can help prevent early-season disease issues, their efficacy is limited. “Three to four weeks is about the timeframe that seed treatments hold up,” she says. “We had enough water and conditions for disease were ideal for longer than that, so even with a seed treatment, there’s enough pressure by the pathogen on the host plant that disease occurred anyway.”

Sudden Death Syndrome is one of several disease and best concerns that come with wet weather.

Sudden death syndrome is another disease concern due to the wet conditions early in the season. Caused by a fungus, SDS has the potential to significantly reduce yields. Bissonnette says that some infections likely happened early in the season.

“If we get wet weather at flowering, that can exacerbate it also, and that’s when the symptoms — a yellowing and dying off of the tissue between the veins on the soybean leaves — start showing up,” she says. “The earlier in flowering that those symptoms appear, the more significant yield losses can be.”

While no treatment exists for SDS, producers should scout their fields to determine if the disease, which typically begins as hot spots, is present. Noting the location of these hot spots is key. The fungus lives in the soil, Bissonnette says, so care should be taken not to spread it further through tillage practices.

Another concern due to flooding is the spread of soybean cyst nematode into fields that were previously “nematode free.”

“The cysts themselves actually can float in water, so with all the water and soil movement that we’ve had, there’s the possibility that SCN will show up in fields where it hasn’t been before,” says Bissonnette, who adds that those growing food-grade soybeans need to pay particular attention to SCN, as none of those varieties have resistance.

“This fall will be an opportune time to test for SCN, especially those fields that will be planted to soybean in 2020,” she says.

As the soybean crop progresses and reaches early to mid-reproductive stages, a bevy of different diseases can come into play, Bissonnette advises. Producers should monitor for frogeye leaf spot as flowering stages near.

Frogeye Leaf Spot is recognizable by the round, tan spot surrounded by a purple-black border.

“If we maintain these humid conditions and have dew in the mornings, we’re going to start seeing frogeye show up,” she says. “At early pod development, around the R3 growth stage, is the best timing for a fungicide application to control most foliar diseases.”

At the R5 stage, producers should be on the lookout for Cercospora leaf spot and purple seed stain, which often appear together, but not always. Bronzing of leaves in the upper canopy is the telltale sign of Cercospora, and seeds may become infected through their attachment to the pod. The discoloration ranges from pink to pale or dark purple on the seed coat.

Bissonnette says that timeliness of harvest this year is going to be critical for reducing seed quality issues associated with late-season diseases. Should warm, wet weather occur during pod fill and maturity, producers may see the development of pod and stem blight and Phomopsis seed decay, which are both caused by the same fungus.

“These diseases are worsened by delayed harvest, so getting beans out as soon as possible is really going to be key,” she adds.

Excess moisture did delay planting at the Missouri Soybean Association’s Bay Farm Research Facility south of Columbia. However, research plots — including the crossing block for the lines of conventional, non-GMO soybean that are part of the North Missouri Soybean Breeding Program — are looking good, says Greg Luce, the Association’s director of research.

“We’re just now entering the time when the breeding team will start to get busy making their crosses of the varieties for next year,” he says. “It’s been pushed back a bit due to the later planting, but the real work of the soybean breeders is happening now.”

Like most farms across the state, Luce says Bay Farm still has adequate soil moisture, especially for mid-July. While overall yields will be expected to be lower this year because of the late planting, he says the most critical time for the soybean crop is yet to come.

“Soybean yield is determined late in the growing season, and right now, we’re in this midseason time where all we can do is wait and see,” he says. “September is going to be a really important month for us. If we can get adequate growth and development of the soybean crop and then we catch some late rains, that’s what will make or break us.”

EDITOR’S NOTE: This is the fourth article in a yearlong series examining the production of conventional, non-GMO soybeans in the Show-Me State. Missouri Soybean Farmer will provide insight into both agronomic challenges and marketing opportunities afforded to those who are raising conventional beans in 2019. This issue, we examine the current state of the 2019 crop. In the October issue, Missouri Soybean Farmer continues its series on growing conventional soybeans with a look toward preparing for harvest.

Find the rest of the issue here.