Liming, however, is the best long-term solution to this problem if soybeans are to be grown regularly. Recommendations Soybeans planted on soils other than sands that have had a well-nodulated crop within the past three to five years usually do not respond to inoculation, although inoculation is cheap insurance in these cases. This is if the pH is above 6.0. Inoculate sandy soils every year. Fields with no history of soybeans require inoculation.
Many fungicides used for seed treatment are harmful to rhizobia.
They should never be used with seed-applied inoculants or preinoculated seed. However, Thiram is compatible with rhizobia. But, to maintain maximum rhizobia numbers, plant Thiram-treated seed soon after inoculation. The information presented in this NebGuide supplied with the understanding that no discrimination is intended, nor endorsement implied, by the Nebraska Cooperative Extension. Kenneth R. Bolen, Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources.