Research conducted at Michigan State University (MSU) and Ohio State University (OSU) and in Ontario has demonstrated that treating soybean seed with bacterial inoculants is a profitable practice, even in fields having a history of soybean production.

MSU and OSU studies showed that the average yield increase for fields planted with inoculated seed was 1.3 bu./acre across multiple locations and years. Research by the Ontario Ministry of Agriculture, Food and Rural Affairs showed an average increase of 1 bu./acre on 11 of 16 sites.

“The really exciting information to come out of this was that the average yield increase in the top five sites was 3.5 bu./acre,” says Mike Staton, MSU Extension agriculture and natural resources educator. “The bottom line is that soybean producers should always inoculate soybean seed regardless of the previous crop rotation; it’s inexpensive and can contribute to a significant yield increase.”

Because inoculants contain living bacterial cells, they must be stored and handled properly. Before planting, store them in a cool place out of direct sunlight. During planting season, keep the packets cool and out of the sun. A pickup truck cab is not a good place to store inoculants – it takes only one hour in the sun to kill the bacterial cells.

Always follow the product’s instructions when applying inoculants to the seed, and make sure that the inoculants you plan to apply are compatible with your seed treatments. Manufacturers and seed suppliers are the best source of compatibility information, Staton notes.

For more information about improving Michigan’s soybean crop, visit the Soybean 2010 Web page at http://web1.msue.msu.edu/soybean2010/. Soybean 2010 was developed to help Michigan growers increase soybean yields and farm profitability by 2010. Funding is provided by MSU Extension; Project GREEEN (Generating Research and Extension to meet Economic and Environmental Needs), the plant industry initiative at MSU; and the Michigan Soybean Promotion Committee.