The use of biostimulant seed treatments (BST) in soybean (Glycine max (L.) Merr.) is a growing market, with many different products and active ingredients (microorganisms) available. Companies promote the use of biostimulant seed treatment products by claiming several potential benefits to crop production, including seed yield increase. There are limited field evaluations on the efficacy of biostimulant seed treatments to increase soybean seed yield in the USA, and many of the microorganisms included in biostimulant products that are marketed to soybean farmers have never been documented in the peer-reviewed literature. The Science for Success team evaluated the effect of several commercially available biostimulant seed treatment products on soybean seed yield in 2022 and 2023 at 103 sites across 22 states. No significant yield differences were observed due to biostimulant seed treatment across and within clusters in both years. We believe that the lack of yield response may have been due to factors such as competition of active ingredients with native soil microorganisms or lack of favorable conditions for plant-microbe interactions. Overall results suggest that management practices, such as row spacing, seeding rate, foliar insecticide, and tillage affect yield more than any of the examined biostimulant seed treatments.
- Agricultural Systems
- Crop Management