Maximizing Soybean Yields: Insights from Dr. Cheryl Reese on Precision Farming, Genetics, and Agronomic Practices

There is a lot that goes into getting the best soybean yields. Dr. Cheryl Reese at South Dakota State University lectures students and farmers on the subject and says it begins with precision farming, scouting soybean fields and working closely with suppliers.

“If I have a white mold problem, the first thing I’m going to do is talk to my seed dealer about varieties that are more resistant to white mold,” said Reese. “Soybean cyst nematode (SCN) is the same deal. If I’m planting early in the springtime, I want soybeans that have a tough root system so I may be looking at phytophthora-resistant genes.”

Dr. Reese teaches crop production courses for soybeans, corn and wheat and is a specialist in soils and fertility.

Dr. Reese analyzed data from the 2023 South Dakota Soybean Yield Contest and spoke at the AgOutlook Conference in December about agronomic practices that result in higher yields. In an interview for The Soybean POD podcast, Reese explained that it's a good idea to keep historical records of specific fields so genetics can be tailored to those fields. Specifically addressing her area of expertise in fertility, Dr. Reese talked about assessing late season nitrogen requirements of Upper Great Plains soybeans.

“A lot of yield can be developed yet in August, because we’re filling those pods, so [the producer] asks the question of ‘70 bushels; do I have enough nitrogen in the soil?’ Well, the studies that a lot of land grant universities have done in the north central states, we’ve seen sporadic, occasional yield improvement with an in-season N. The research we’ve done within our research group, we have not ever seen a yield increase with a late season N application.”

When should a grower plant? It’s often said that earlier planted soybeans take advantage of greater sunlight and perform better. Dr. Cheryl Reese gives this caveat.

“It’s all dependent upon weather. If I’m going to plant soybeans and I want to push my yield, I’m going to plant early, I’m going to plant a higher relative maturity. Longer relative maturities have more time for biomass, to collect sunlight, set nodes, produce pods, produce yield. But if when I planted that field early, it so happens to coincide with a precipitation event that starts the growth of white mold in my field, then maybe my later planted field may have a higher yield if I cannot control that white mold. So there’s many factors involved with yield in soybeans,” said Reese. “And the one thing we can’t control is the weather.”

Hear more from Dr. Cheryl Reese on The Soybean Pod wherever you get your podcasts.