Farmers planted almost 800,000 acres of soybean in 2025, and LSU AgCenter research is important to identifying high-quality soybean varieties and establishing cultural practices that may lead to maximum yield.

AgCenter soybean specialist David Moseley spearheaded official variety trials (OVT) for 68 varieties. Additionally, there were 25 core-block variety trials in 11 parishes for 2025-2026. Data from those trials were published in the LSU AgCenter 2026 Soybean Variety Yields and Production Practices publication.

“It’s important for farmers to check the new book each year,” said Moseley. “We keep evaluating to see which ones have the highest yield and work across the most acres and environments.”

In the most recent trials, the top variety yielded 5% more than the average variety, according to Moseley. For the maturity group 4.5 to 4.9 core block, the top three yielding varieties had above average yield for most of the locations.

Additionally, Moseley has begun a unique study analyzing planting date by leaf shape. A soybean near-isogenic line was recently developed that had only one genetic difference with the parent — a narrow leaf, instead of the traditional broad one.

“There’s an idea that we’ve actually developed too much vegetation and possibly that’s why we’re seeing green stem,” said Moseley. “Also, maybe too much foliage means we use more water than we need, or it blocks air flow, increasing disease pressure.”

“Could less vegetation on the narrow leaf be an advantage?” asked Moseley.

Moseley’s team has been evaluating multiple foliar applications that companies are alleging mitigate stress and increase yield. The tests are being conducted at the Dean Lee Research and Extension Center in Alexandria.

“I’m just doing research to either confirm or reject claims these products are making a difference,” said Moseley. “If something is working, I want to find it and let farmers know what it is.”

Researchers are able to do multiple replicated small plots at the research station but would not be able to test that many products on the farm.

“If we see something that’s working at the station, we can scale it up to the farm,” he said. “Without that, we just wouldn’t be able to look at enough products and wouldn’t be able to replicate it for data and analysis. That’s the power of the research station.”

LSU AgCenter soybean scientists are also participating in several national soybean trials with Science for Success, a group of university researchers from different states.

In one, researchers are investigating different planting dates: earlier than optimum, optimum and later than optimum. After three weeks, more soybean is planted in the lower than optimum group.

“So we can see if replanting was economical or if we didn’t need to replant,” said Moseley.

Moseley has another trial, not part of the national study, focusing on planting date by population without any replanting. He has also begun on-farm trials with granular and foliar potassium fertilizers, basing these on soil tests.

AgCenter researchers tested a non-paraquat harvest-aid product to measure the most economical timing of application. They found it can help with green stem, it did not decrease seed quality, nor did it decrease yield when sprayed at R7.5 growth stage, said Moseley.

The Science for Success group is also working on developing a tool that could help resolve problems like “hidden hunger,” where asymptomatic potassium deficiency causes decreased yields.

“The tool would allow you to know how much potassium to put on in-season, based upon your leaf tissue analysis,” said Moseley.

“You work together with other states and, instead of having one field or two, you have multiple fields across the nation,” Moseley said. “That data is so much more powerful.”

Soybean core block locations: Acadia, Avoyelles, Beauregard, Bossier, East Baton Rouge, Franklin, Pointe Coupee, Rapides, Richland, St. Landry, West Carroll

Soybean trial that uses replants in certain fields, as part of wider research investigating the outcome of different planting dates. Photos by David Moseley

A recently developed soybean line with less leaf growth (right) compared to a standard size leaf (left). The LSU AgCenter has recently begun a study of soybean plants with different leaf sizes.