Managing Soybean Plant Type
May 17, 2024
The growth habits of soybean plants are influenced mainly by genetics and growing conditions. When managing a soybean crop, plant structure may be worth considering. Other factors, among many, influencing soybean growth may include planting date, row spacing, seeding rate, product planted, soil type, rainfall/irrigation, nematode infestations, and weed control.
For this article, indeterminant soybean products are discussed. Indeterminant soybean products are grown most often in the northern part of the United States. They continue to grow vegetatively after they start flowering and until seed development begins. Flowering is triggered by increased periods of darkness, or shorter periods of daylight.
Adapting management practices related to soybean plant structure is often less effective on yield potential than other factors, such as planting date and population. Soybean plants are highly responsive to their environment. At high populations, soybean plants grow taller and slimmer, despite their genetic growth habits. The taller the plant grows, the risk for lodging increases. Early-season lodging increases the risk of lost yield potential from reduced photosynthetic activity. Late-season lodging increases the risk of lost yield potential from inability to adequately harvest all plants. High populations are also at higher risk for foliar disease development because of less air movement throughout the canopy, particularly with white mold.
If planted at low seeding rates and in more challenging soil conditions, a tall/thin soybean product is typically shorter and bushier. Most soybean products grown for commercial production tolerate lower seeding rates and compensate for the added space by adding lateral branches, and increased nodes. Conversely, if a soybean product is characterized as “short”, management strategies to help maximize performance may include placement on a higher quality soil type and earlier planting to help the plant to maximize vegetative growth.
Another soybean management consideration is planting date. The longer a soybean plant accumulates sunlight, the more foliage the soybean plant can grow.
Although there are many factors influencing soybean growth habits, soybean plants are very adaptable to their environment and very resilient. Consider the plant type structure as one of many factors when managing your soybean crop. However, proper placement helps to maximize plant structure characteristics as it relates to return on investment.
For additional information on soybean seeding rates, please visit these Bayer Crop Science research articles:
The Effect of Seeding Rate and Planting Date on Soybean Yield Potential and The Effect of Row Width and Planting Rate on Agronomic Characteristics of Soybeans
Amanda Schwartz
Channel Agronomist
Source
McWilliams, D.A., Berglund, D.R., and Endres, G.J. 1999. Soybean growth and management quick guide. A-1174. North Dakota State University. https://library.ndsu.edu/ir/bitstream/handle/10365/5453/a1174.pdf?sequence=1
Web source verified 3/26/24. 1110_377851